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Author: Grafiati

Published: 4 June 2021

Last updated: 10 February 2022

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1

Politi, Katerina, and Scott Gettinger. "Perfect ALKemy: Optimizing the Use of ALK-Directed Therapies in Lung Cancer." Clinical Cancer Research 20, no. 22 (September 16, 2014): 5576–78. http://dx.doi.org/10.1158/1078-0432.ccr-14-2306.

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2

Yamamoto, Eiji, Satoshi Ukigai, and Hajime Ito. "Boryl substitution of functionalized aryl-, heteroaryl- and alkenyl halides with silylborane and an alkoxy base: expanded scope and mechanistic studies." Chemical Science 6, no. 5 (2015): 2943–51. http://dx.doi.org/10.1039/c5sc00384a.

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A transition-metal-free method has been developed for the boryl substitution of functionalized aryl-, heteroaryl- and alkenyl halides using a silylborane/alkoxy-base reagent. Borylation of (Z)-alkenyl halides proceeded in a stereoretentive manner.

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3

Phipps, Erik J. T., Tiffany Piou, and Tomislav Rovis. "Rhodium(III)-Catalyzed Cyclopropanation of Unactivated Olefins Initiated by C–H Activation." Synlett 30, no. 15 (July 22, 2019): 1787–90. http://dx.doi.org/10.1055/s-0039-1690130.

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We have developed a rhodium(III)-catalyzed cyclopropanation of unactivated olefins initiated by an alkenyl C–H activation. A variety of 1,1-disubstituted olefins undergo efficient cyclopropanation with a slight excess of alkene stoichiometry. A series of mechanistic interrogations implicate a metal carbene as an intermediate.

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4

Glover, SA, GP Hammond, DG Harman, JG Mills, and CA Rowbottom. "Cyclization of Alkoxyiminyl Radicals Onto Olefins: Formation of 2-Alkoxy-Delta(1)-Pyrrolines, 4,5-Dihydrooxazoles and 5,6-Dihydrol-4h-1,3-Oxazines." Australian Journal of Chemistry 46, no. 8 (1993): 1213. http://dx.doi.org/10.1071/ch9931213.

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Alkoxyiminyl radicals, generated by photolysis of N-bromo imidates, undergo exo-1,5 and exo-1,6 cyclization onto olefins on the O-alkyl side chains giving good yields of 4,5-dihydrooxazoles and 5,6-dihydro-4H-1,3-oxazines, respectively. exo-1,5 Cyclization onto an olefin on the iminyl side chain gives 2-alkoxy-Δ1-pyrrolines. 4,5-Dihydrooxazole formation is more favourable than cyclization to 2-alkoxy-Δ1-pyrrolines and both reactions are irreversible. These preferences are supported by MNDO molecular orbital calculations which predict that both processes are exothermic but cyclization onto the O- alkenyl side chain has a lower ΔH‡.

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5

Maraswami, Manikantha, and Teck-Peng Loh. "Transition-Metal-Catalyzed Alkenyl sp2 C–H Activation: A Short Account." Synthesis 51, no. 05 (January 23, 2019): 1049–62. http://dx.doi.org/10.1055/s-0037-1611649.

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Alkenes are ubiquitous in Nature and their functionalization continues to attract attention from the scientific community. On the other hand, activation of alkenyl sp2 C–H bonds is challenging due to their chemical properties. In this short account, we elucidate, discuss and describe the utilization of transition-metal catalysts in alkene activation and provide useful strategies to synthesize organic building blocks in an efficient and sustainable manner.1 Introduction2 Breakthrough3 Controlling E/Z, Z/E Selectivity3.1 Esters and Amides as Directing Groups3.2 The Chelation versus Non-Chelation Concept4 Other Alkene Derivatives5 Intramolecular C–H Activation6 Conclusion and Future Projects

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6

Listunov, Dymytrii, Valérie Maraval, Nathalie Saffon-Merceron, Sonia Mallet-Ladeira, Zoia Voitenko, Yulian Volovenko, Yves Génisson, and Remi Chauvin. "On terminal alkynylcarbinols and derivatization thereof." French-Ukrainian Journal of Chemistry 3, no. 1 (2015): 21–28. http://dx.doi.org/10.17721/fujcv3i1p21-28.

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The chemistry of three prototypes of secondary alkynylcarbinols (ACs), recently highlighted as challenging targets in anti-tumoral medicinal chemistry, is further documented by results on n-alkyl, alkynyl and alkenyl representatives. The N-naphthyl carbamate of an n-butyl-AC is thus characterized by X-ray crystallography. A novel dialkynylcarbinol (DAC) with synthetic potential is described, namely the highly dissymmetrical triisopropylsilyl-protected version of diethynylmethanol. The latter is shown to act as a dipolarophile in a selective Huisgen reaction with benzyl azide under CuAAC click conditions, giving an alkenyl-AC, where the alkene unsaturation is embedded in a 1,4-disubstituted 1,2,3-triazole ring, as confirmed by X-ray crystallography.

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7

Music, Arif, and Dorian Didier. "Organocerium: A New Contender for Halogen–Metal Exchanges." Synlett 30, no. 16 (June 3, 2019): 1843–49. http://dx.doi.org/10.1055/s-0037-1611843.

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In the context of our current research on dependable and sustainable methods for C–C bond-forming reactions, we have recently developed new strategies to generate organocerium reagents through simple bromide–cerium exchanges. n-Bu3Ce enabled a fast and general access to functionalized triaryl- and alkenyl cerium species from the corresponding aryl- and alkenyl bromides. A broad range of these new organocerium species was engaged in Zweifel’s olefination, allowing for the synthesis of widely substituted alkene derivatives in a stereospecific way. Herein, we place the formation of organocerium species in the context of known organometallic reagents (Li, Mg, Zn, Cu, Ca, La, and Sm) generated through halogen–metal exchange reactions and their application in further transformations.

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8

Tang, Xinjun, and Armido Studer. "Alkene 1,2‐Difunctionalization by Radical Alkenyl Migration." Angewandte Chemie International Edition 57, no. 3 (January 15, 2018): 814–17. http://dx.doi.org/10.1002/anie.201710397.

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9

Tang, Xinjun, and Armido Studer. "Alkene 1,2‐Difunctionalization by Radical Alkenyl Migration." Angewandte Chemie 130, no. 3 (December 14, 2017): 822–25. http://dx.doi.org/10.1002/ange.201710397.

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10

Gu, Zheng-Yang, Yang Wu, Xiaoguang Bao, Ji-Bao Xia, and Feng Jin. "Intermolecular C–H Amidation of Alkenes with Carbon Monoxide and Azides via Tandem Palladium Catalysis." Synthesis 53, no. 18 (February 26, 2021): 3361–71. http://dx.doi.org/10.1055/a-1401-4486.

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AbstractAn atom- and step-economic intermolecular multi-component palladium-catalyzed C–H amidation of alkenes with carbon monoxide and organic azides has been developed for the synthesis of alkenyl amides. The reaction proceeds efficiently without an ortho-directing group on the alkene substrates. Nontoxic dinitrogen is generated as the sole by-product. Computational studies and control experiments have revealed that the reaction takes place via an unexpected mechanism by tandem palladium catalysis.

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11

Slivka, Mikhailo, Nataliya Korol, Ivan Rusyn, and Vasyl Lendel. "Synthesis of [1,3]thiazolo[3,2-b][1,2,4]triazol-7-ium and [1,2,4]triazolo[5,1-b][1,3]thiazin-4-ium salts via regioselective electrophilic cyclization of 3-[(2-alken-1-yl)sulfanyl]-4H-1,2,4-triazoles." Heterocyclic Communications 21, no. 6 (December 1, 2015): 397–401. http://dx.doi.org/10.1515/hc-2015-0158.

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AbstractA convenient procedure for the regioselective preparation of [1,3]thiazolo[3,2-b][1,2,4]triazol-7-ium 10 and [1,2,4]triazolo[5,1-b][1,3]thiazin-4-ium salts 9 via regioselective electrophilic cyclization of 3-[(2-alken-1-yl)sulfanyl]-4H-1,2,4-triazoles 3 is reported. Direction of electrophilic heterocyclization strongly depends on nature of the alkenyl substitutent.

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12

Collis, Gavin E., and Dieter Wege. "Approaches to Cyclopropa-Fused Quinones. The Synthesis and Photolysis of Some 4,9-Disubstituted 3,3-Dimethyl-3H-benz[f]indazoles." Australian Journal of Chemistry 56, no. 9 (2003): 903. http://dx.doi.org/10.1071/ch03060.

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Addition of 2-diazopropane to 1,4-naphthoquinone at low temperature, followed by in situ enolization and acetylation or silylation gave 3,3-dimethyl-1H-benz[f]indazol-4,9-diyl diacetate and 3,3-dimethyl-9-(t-butyl-dimethylsilyloxy)-1H-benz[f]indazol-4-ol, respectively. Functional group manipulation of the latter compound provided a number of other 4,9-disubstituted 3,3-dimethyl-3H-benz[f]indazoles. Irradiation of the diacetate led to clean extrusion of nitrogen to give the naphtho[b]cycloproparene and an alkene. Attempts to elaborate the cycloproparene into the derived cyclopropanaphthoquinone were unsuccessful. Of the other 4,9-disubstituted 3,3-dimethyl-3H-benz[f]indazoles examined, only the compound possessing an acetoxy group at C9 was photoactive, and afforded the expected cycloproparene and alkene. Compounds bearing a hydroxy or alkoxy group at C9 were photochemically inert.

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13

Wang, Honggen, Yao-Fu Zeng, Wen-Xin Lv, and Dong-Hang Tan. "Synthetic Transformations of Alkenyl MIDA Boronates toward the Efficient Construction of Organoborons." Synlett 29, no. 11 (March 28, 2018): 1415–20. http://dx.doi.org/10.1055/s-0036-1591958.

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The attachment of N-methyliminodiacetyl boron (MIDA boron) to alkenes leads to a new type of activated alkenes. Synthetic manipulation of the alkene double bond while retaining the boron moiety offers an unprecedented opportunity for the construction of organoborons. These reactions feature unique reactivity, good regioselectivity, and they can be used to access organoborons that are historically difficult to prepare. Herein, we give a brief summary of advances in the use of alkenyl MIDA boronates as starting materials for organoboron synthesis. Mechanisms are discussed where relevant.

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14

Ito, Hajime, Eiji Yamamoto, Satoshi Maeda, and Tetsuya Taketsugu. "Transition-Metal-Free Boryl Substitution Using Silylboranes and Alkoxy Bases." Synlett 28, no. 11 (April 26, 2017): 1258–67. http://dx.doi.org/10.1055/s-0036-1588772.

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Silylboranes are used as borylation reagents for organohalides in the presence of alkoxy bases without transition-metal catalysts. PhMe2Si–B(pin) reacts with a variety of aryl, alkenyl, and alkyl halides, including sterically hindered examples, to provide the corresponding organoboronates in good yields with high borylation/silylation ratios, showing good functional group compatibility. Halogenophilic attack of a silyl nucleophile on organohalides, and subsequent nucleophilic attack on the boron electrophile are identified to be crucial, based on the results of extensive theoretical and experimental studies. This borylation reaction is further applied to the first direct dimesitylboryl (BMes2) substitution of aryl halides using Ph2MeSi–BMes2 and Na(O-t-Bu), affording aryldimesitylboranes, which are regarded as an important class of compounds for organic materials.1 Introduction2 Boryl Substitution of Organohalides with PhMe2Si–B(pin)/Alkoxy Bases3 Mechanistic Investigations4 DFT Mechanistic Studies Using an Artificial Force Induced Reaction (AFIR) Method5 Dimesitylboryl Substitution of Aryl Halides with Ph2MeSi–BMes2/Na(O-t-Bu)6 Conclusion

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15

Zahedifar, Mahboobeh, and Hassan Sheibani. "Unexpected Products from Mesoionic 1,3-Thiazinium and Oxazinium Olates: A Novel Access to 3,5-Diaryl-1,3-thiazine-2,4,6-trione and Alkoxy-3,5-diphenyl-3H-1,3-oxazine-2,6-dione Derivatives." Australian Journal of Chemistry 67, no. 9 (2014): 1201. http://dx.doi.org/10.1071/ch14095.

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The condensation of (chlorocarbonyl)ketenes 1 with N-phenylthiocarbamates 2 and N-phenylcarbamates 6 is postulated to lead to the formation of unstable mesoionic 1,3-thiazinium 4-olates I or 1,3-oxazinium 4-olates II, respectively. At room temperature, appropriately substituted mesoionic 1,3-thiazinium 4-olates I eliminated the corresponding alkene with generation of 3,5-diaryl-1,3-thiazine-2,4,6-trione derivatives 3. However, the methoxy-substituted compound 5 was stable at room temperature at least for several weeks. In the case of the mesoionic1,3-oxazinium 4-olates II an alkyl group migration affords 4-alkoxy-3,5-diphenyl-3H-1,3-oxazine-2,6-diones 7.

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16

Ma, Jun, Jeremy W. Bartels, Zhou Li, Ke Zhang, Chong Cheng, and Karen L. Wooley. "Synthesis and Solution-state Assembly or Bulk State Thiol-ene Crosslinking of Pyrrolidinone- and Alkene-functionalized Amphiphilic Block Fluorocopolymers: From Functional Nanoparticles to Anti-fouling Coatings." Australian Journal of Chemistry 63, no. 8 (2010): 1159. http://dx.doi.org/10.1071/ch10011.

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With an ever increasing interest in the combined functionality and versatility of materials, increasing demands are placed on synthetic methodologies by which to produce such materials. This work demonstrates the preparation of block copolymers having fluorocarbon content, pyrrolidinone units, and alkene groups as complex building blocks for the assembly of discrete nanoparticles in solution and, alternatively, transformation into sophisticated crosslinked networks. Reversible addition–fragmentation chain transfer (RAFT) polymerization is a facile tool for the synthesis of well-defined polymers containing imbedded side-chain functionalities. In this work, the synthesis of well-defined multifunctional fluorinated polymers bearing pendant pyrrolidinone groups, and block copolymers bearing both pyrrolidinone and alkenyl groups on different segments was achieved, by using RAFT polymerizations of unique bifunctional monomers. Upon micellization, the amphiphilic diblock copolymers were transformed into regioselectively-functionalized nanoparticles. Further transformations of pyrrolidinone- and alkene-dual functionalized-block copolymers into complex amphiphilic networks were accomplished by highly efficient UV-induced thiol-ene reactions. Whether as discrete nanoparticles or nanoscopically-segregated crosslinked networks, these materials have great potential for several diverse technologies, including as anti-fouling materials.

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17

Huynh, Lam K., Kyle Barriger, and Angela Violi. "Kinetics Study of the OH + Alkene → H2O + Alkenyl Reaction Class." Journal of Physical Chemistry A 112, no. 7 (February 2008): 1436–44. http://dx.doi.org/10.1021/jp077028i.

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18

Coldham, Iain, Adam J. M. Burrell, Hélène D. S. Guerrand, Luke Watson, Nathaniel G. Martin, and Niall Oram. "Synthesis of fused tricyclic amines unsubstituted at the ring-junction positions by a cascade condensation, cyclization, cycloaddition then decarbonylation strategy." Beilstein Journal of Organic Chemistry 8 (January 18, 2012): 107–11. http://dx.doi.org/10.3762/bjoc.8.11.

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Heating aldehydes that contain a protected hydroxymethyl group, a tethered alkyl chloride and a tethered alkenyl group at the α-position of the aldehyde with an amine sets up a cascade (tandem) reaction sequence involving condensation to an intermediate imine, then cyclization and formation of an intermediate azomethine ylide and then intramolecular dipolar cycloaddition. The fused tricyclic products are formed with complete or very high stereochemical control. The hydroxymethyl group was converted into an aldehyde – which could be removed to give the tricyclic amine products that are unsubstituted at the ring junction positions – or was converted into an alkene, which allowed the formation of the core ring system of the alkaloids scandine and meloscine.

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19

Nason, Trevor R., Melbourne J. Schriver, Arthur D. Hendsbee, and Jason D. Masuda. "Crystal structure determination as part of an ongoing undergraduate organic laboratory project: 5-[(E)-styryl]-1,3,4-oxathiazol-2-one." Acta Crystallographica Section E Crystallographic Communications 73, no. 9 (August 4, 2017): 1298–301. http://dx.doi.org/10.1107/s2056989017011264.

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The title compound, C10H7NO2S, provides the first structure of an α-alkenyl oxathiazolone ring. The phenyl ring and the oxathiazolone groups make dihedral angles of 0.3 (3) and −2.8 (3)°, respectively, with the plane of the central alkene group; the dihedral angle between the rings is 2.68 (8)°. A careful consideration of bond lengths provides insight into the electronic structure and reactivity of the title compound. In the crystal, extended π-stacking is observed parallel to thea-axis direction, consisting of cofacial head-to-tail dimeric units [centroid–centroid distance of 3.6191 (11) Å]. These dimeric units are separated by a slightly longer centroid–centroid distance of 3.8383 (12) Å, generating infinite stacks of molecules.

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20

Bruffaerts, Jeffrey, Alexandre Vasseur, and Ilan Marek. "Alkene-Zipper Catalyzed Selective and Remote Retro-ene Reaction of Alkenyl Cyclopropylcarbinol." Advanced Synthesis & Catalysis 360, no. 7 (February 13, 2018): 1389–96. http://dx.doi.org/10.1002/adsc.201701481.

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21

Maton, Cedric, Neil R. Brooks, Luc Van Meervelt, Koen Binnemans, Stijn Schaltin, Jan Fransaer, and Christian V. Stevens. "Synthesis and Properties of Alkoxy- and Alkenyl-Substituted Peralkylated Imidazolium Ionic Liquids." ChemPhysChem 14, no. 15 (September 23, 2013): 3503–16. http://dx.doi.org/10.1002/cphc.201300611.

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22

Maier, Martin, and Alexander Riefert. "Approach to the Core Structure of 15-epi-Exiguolide." Synthesis 50, no. 16 (July 16, 2018): 3131–45. http://dx.doi.org/10.1055/s-0037-1610821.

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The synthesis of seco acid 41 of the macrolactone part of 15-epi-exiguolide, containing a bis-pyran subunit and a trans double bond, is described. Key features of the synthetic strategy include a Feringa–Minnaard asymmetric organocuprate addition to unsaturated ester 17 to set the stereocenter at C15. The derived acid 8 (C9–C16 fragment) was ideally suited for combination with aldehyde 9 (C17–C21 fragment) via an aldol strategy leading to β-lactone 25 which upon thermal decarboxylation provided alkene 26. Chain extension led to propargylic alcohol 7. Treatment of 7 with a LAu+ catalyst promoted a Meyer–Schuster rearrangement to enone 30 that led to cis-tetrahydropyran 31 via intramolecular oxa-Michael reaction. The second pyran ring was prepared from alkoxy ketone 5 by reductive cyclization. The further steps toward macrolactone 43 were hampered by the epimeric mixture at C5.

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23

Čeković, Ẑivorad, and Dimitar Ilijev. "Intramolecular cyclization of alkenyl radicals generated by 1,5-hydrogen transfer to alkoxy radicals." Tetrahedron Letters 29, no. 12 (January 1988): 1441–44. http://dx.doi.org/10.1016/s0040-4039(00)80319-6.

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24

Maraswami, Manikantha, Thomas Diggins, Jeffrey Goh, Raymond Tio, Wan Qing Renee Ong, Hajime Hirao, and Teck-Peng Loh. "Intramolecular Alkene–Alkene Coupling via Rh(III)-Catalyzed Alkenyl sp2 C–H Functionalization: Divergent Pathways to Indene or α-Naphthol Derivatives." ACS Catalysis 11, no. 18 (September 1, 2021): 11494–500. http://dx.doi.org/10.1021/acscatal.1c03175.

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25

Barluenga, José, Rubén Vicente, Luis A. López, and Miguel Tomás. "Efficient synthesis of 2-alkoxy-1,3-butadienes by methylenation of alkenyl Fischer carbene complexes." Arkivoc 2007, no. 4 (December 2, 2006): 356–63. http://dx.doi.org/10.3998/ark.5550190.0008.432.

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26

Kalena, Govind P., Padmanava Pradhan, and Asoke Banerji. "Stereo- and regioselectivity of intramolecular 1,2-arene-alkene photocycloaddition in 2-alkenyl-4-chromanones." Tetrahedron 55, no. 11 (March 1999): 3209–18. http://dx.doi.org/10.1016/s0040-4020(98)01134-x.

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27

Torres, M. Rosario, Aurea Perales, and Josep Ros. "Insertion of carbon disulfide into ruthenium-alkenyl bonds. Formation of an alkene dithiocarboxylate ligand." Organometallics 7, no. 5 (May 1988): 1223–24. http://dx.doi.org/10.1021/om00095a033.

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28

Xu, Songgen, Peiyu Geng, Yuling Li, Guixia Liu, Lei Zhang, Yinlong Guo, and Zheng Huang. "Pincer Iron Hydride Complexes for Alkene Isomerization: Catalytic Approach to Trisubstituted (Z)-Alkenyl Boronates." ACS Catalysis 11, no. 16 (July 30, 2021): 10138–47. http://dx.doi.org/10.1021/acscatal.1c02432.

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29

Voigt, Katharina, Ute Schick, Frank E. Meyer, and Armin de Meijere. "Rate Enhancement of Palladium-Catalyzed Alkene to Alkenyl and Aryl Halide Couplings under High Pressure." Synlett 1994, no. 03 (1994): 189–90. http://dx.doi.org/10.1055/s-1994-22789.

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30

Lakshmi, A. B., and Jampani Madhusudana Rao. "Intramolecular cross-ring enone–alkene photoannelation in 6-(ω-alkenyl)-cyclohex-2-en-1-ones." J. Chem. Soc., Chem. Commun., no. 7 (1991): 476–77. http://dx.doi.org/10.1039/c39910000476.

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31

Grossi, Vincent, Damien Mollex, Arnauld Vinçon-Laugier, Florence Hakil, Muriel Pacton, and Cristiana Cravo-Laureau. "Mono- and Dialkyl Glycerol Ether Lipids in Anaerobic Bacteria: Biosynthetic Insights from the Mesophilic Sulfate Reducer Desulfatibacillum alkenivorans PF2803T." Applied and Environmental Microbiology 81, no. 9 (February 27, 2015): 3157–68. http://dx.doi.org/10.1128/aem.03794-14.

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ABSTRACTBacterial glycerol ether lipids (alkylglycerols) have received increasing attention during the last decades, notably due to their potential role in cell resistance or adaptation to adverse environmental conditions. Major uncertainties remain, however, regarding the origin, biosynthesis, and modes of formation of these uncommon bacterial lipids. We report here the preponderance of monoalkyl- and dialkylglycerols (1-O-alkyl-, 2-O-alkyl-, and 1,2-O-dialkylglycerols) among the hydrolyzed lipids of the marine mesophilic sulfate-reducing proteobacteriumDesulfatibacillum alkenivoransPF2803Tgrown onn-alkenes (pentadec-1-ene or hexadec-1-ene) as the sole carbon and energy source. Alkylglycerols account for one-third to two-thirds of the total cellular lipids (alkylglycerols plus acylglycerols), depending on the growth substrate, with dialkylglycerols contributing to one-fifth to two-fifths of the total ether lipids. The carbon chain distribution of the lipids ofD. alkenivoransalso depends on that of the substrate, but the chain length and methyl-branching patterns of fatty acids and monoalkyl- and dialkylglycerols are systematically congruent, supporting the idea of a biosynthetic link between the three classes of compounds. Vinyl ethers (1-alken-1′-yl-glycerols, known as plasmalogens) are not detected among the lipids of strain PF2803T. Cultures grown on different (per)deuteratedn-alkene,n-alkanol, andn-fatty acid substrates further demonstrate that saturated alkylglycerols are not formed via the reduction of hypothetic alken-1′-yl intermediates. Our results support an unprecedented biosynthetic pathway to monoalkyl/monoacyl- and dialkylglycerols in anaerobic bacteria and suggest thatn-alkyl compounds present in the environment can serve as the substrates for supplying the building blocks of ether phospholipids of heterotrophic bacteria.

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32

Rasyid, Abdullah. "ANALYSIS OF SECONDARY METABOLITES, ANTIBACTERIAL ACTIVITY AND COMPOUND COMPOSITION IN THE SEA CUCUMBER Bohadschia sp. EXTRACT." Jurnal Ilmu dan Teknologi Kelautan Tropis 8, no. 2 (April 6, 2017): 645–53. http://dx.doi.org/10.29244/jitkt.v8i2.15831.

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Bohadschia sp. is one of the sea cucumber species that has potential to be developed as a source of antibacterial from the sea. Samples of sea cucumber Bohadschia sp. used in this study collected from the Ratai bay waters, Lampung. This study aims to determine the type of secondary metabolites, antibacterial activity and compound composition analysis containing in the sea cucumber extract. Identification of secondary metabolites by observation of color reactions, precipitation and foam. The method used to antibacterial activity test was the agar diffusion method, while identification of the composition of compounds performed with Gas Chromatogaphy-Mass Spectroscopy (GC-MS) method.Top of FormThe results showed that the type of secondary metabolites contained in the extract of sea cucumber Bohadschia sp. were steroids and saponins. The extract of sea cucumber Bohadschia sp. showed antibacterial activity against Bacillus subtilis and Vibrio eltor. Results of GC-MS were 12 compounds and have a similarity index same or more than 90%. All compounds consist of organosilicon cyclic, fatty acid, steroid, cyclo alkene and alkena. The compound with biggest abundance was cholest-5-en-3-yl nonanoate (4.89%) and retention time was 37.370 minutes.

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33

Martins, Marcos, Wilson Cunico, Claudio Pereira, Adilson Sinhorin, Alex Flores, Helio Bonacorso, and Nilo Zanatta. "4-Alkoxy-1,1,1-Trichloro-3-Alken-2-ones: Preparation and Applications in Heterocyclic Synthesis." Current Organic Synthesis 1, no. 4 (October 1, 2004): 391–403. http://dx.doi.org/10.2174/1570179043366611.

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34

Menicagli, R., C. Malanga, M. Dell'Innocenti, and L. Lardicci. "Triisobutylaluminum-assisted reductive rearrangement of alkyl 1-alkenyl acetals: an easy synthesis of .beta.-alkoxy alcohols." Journal of Organic Chemistry 52, no. 26 (December 1987): 5700–5704. http://dx.doi.org/10.1021/jo00235a010.

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35

Naeem, Saira, Eleanor Ogilvie, Andrew J. P. White, Graeme Hogarth, and James D. E. T. Wilton-Ely. "The functionalisation of ruthenium(ii) and osmium(ii) alkenyl complexes with amine- and alkoxy-terminated dithiocarbamates." Dalton Transactions 39, no. 17 (2010): 4080. http://dx.doi.org/10.1039/b925536b.

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36

Kryshtal', G. V., G. M. Zhdankina, and E. P. Serebryakov. "The synthesis of 4-(2,6,10-trimethyl-1,3,5,9-undecatetraenyl)benzoic acid based on alkoxy alkene-acetal condensation." Russian Chemical Bulletin 42, no. 5 (May 1993): 870–71. http://dx.doi.org/10.1007/bf00698949.

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37

Bai, Jian-Fei, Hajime Sasagawa, Taiga Yurino, Taichi Kano, and Keiji Maruoka. "In situ generation of N-Boc-protected alkenyl imines: controlling the E/Z geometry of alkenyl moieties in the Mukaiyama–Mannich reaction." Chemical Communications 53, no. 58 (2017): 8203–6. http://dx.doi.org/10.1039/c7cc04674j.

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Readily available Boc-protected Z-alkenyl aminals were used as Z-alkenyl and E-alkenyl imine precursors under acidic conditions. In the Mukaiyama–Mannich reaction of Z-alkenyl Boc-aminals, the E/Z geometry of the products was controlled by the catalyst used.

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38

Hodgson, David M., and Hasanain A. A. Almohseni. "Evolution of a Cycloaddition–Rearrangement Approach to the Squalestatins: A Quarter-Century Odyssey." Synlett 31, no. 16 (June 4, 2020): 1555–72. http://dx.doi.org/10.1055/s-0040-1707127.

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The highs, lows, and diversions of a journey leading to two syntheses of 6,7-dideoxysqualestatin H5 is described. Both syntheses relied on highly diastereoselective n-alkylations of a tartrate acetonide enolate and subsequent oxidation–hydrolysis to provide an asymmetric entry to β-hydroxy-α-ketoester motifs. The latter were differentially elaborated to diazoketones which underwent stereo- and regioselective Rh(II)-catalysed cyclic carbonyl ylide formation–cycloaddition and then acid-catalysed transketalisation to generate the 2,8-dioxabicyclo[3.2.1]octane core of the squalestatins/zaragozic acids at the correct tricarboxylate oxidation level. The unsaturated side chain was either protected with a bromide substituent during the transketalisation or introduced afterwards by a stereoretentive Ni-catalyzed Csp3–Csp2 cross-electrophile coupling.1 Introduction 2 Racemic Model Studies to the Squalestatin/Zaragozic Acid Core3 Asymmetric Model Studies to a Keto α-Diazoester3.1 Dialkyl Squarate Desymmetrisation3.2 Tartrate Alkylation3.2.1 Further Studies on Seebach’s Alkylation Chemistry 4 Failure at the Penultimate Step to DDSQ 5 Second-Generation Approach to DDSQ: A Bromide Substituent Strategy 5.1 Stereoselective Routes to E-Alkenyl Halides via β-Oxido Phosphonium Ylides 5.2 Back to DDSQ Synthesis6 An Alternative Strategy to DDSQ: By Cross-Electrophile Coupling7 Alkene Ozonolysis in the Presence of Diazo Functionality: Accessing α-Ketoester Intermediates8 Summary

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39

Shivaprakash, Shivanna, G. Chandrasekara Reddy, Jerry P. Jasinski, Sean P. Millikan, Courtney E. Duff, and Christopher Glidewell. "A sterically congestedcis-stilbene and its phosphonium salt precursor." Acta Crystallographica Section C Structural Chemistry 71, no. 6 (May 16, 2015): 479–84. http://dx.doi.org/10.1107/s2053229615009110.

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Triphenyl(2,4,5-trimethoxybenzyl)phosphonium chloride is formed in solvent-free form by the reaction under anhydrous conditions between triphenylphosphane and 2,4,5-trimethoxybenzyl chloride, but when it is crystallized from a mixture of ethyl acetate and chloroform in the presence of air it forms a stoichiometric monohydrate, C28H28O3P+·Cl−·H2O, (I). The reactions between the anhydrous phosphonium salt and alkoxy-substituted benzaldehydes, using Wittig reactions in the presence of potassiumtert-butoxide, provide a series of multiply substituted stilbenes, most of which were assigned theZconfiguration on the basis of their NMR spectra. However, no such deduction could be made for the symmetrically substituted (Z)-2,2′,4,4′,5,5′-hexamethoxystilbene, C20H24O6, (II). Compound (II) does in fact have theZconfiguration and the molecular geometry provides evidence for steric congestion around the central double bond; in particular, the central alkene fragment is nonplanar, with a C—C=C—C torsion angle of 7.8 (4)°. In hydrated salt (I), the chloride anions and water molecules are linked by O—H...Cl hydrogen bonds to formC21(4) chains; each cation is linked by C—H...O hydrogen bonds to two different chains, so forming a sheet structure. There are no direction-specific intermolecular interactions in the structure of (II).

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40

Zhang, Peng-Fei, and Zhen-Chu Chen. "Hypervalent Iodine in Synthesis 73: A New Stereoselective Synthesis of 1-(1-alkenyl) Benzotriazoles by the reaction of Alkenyl(phenyl)iodonium Salts with Benzotriazole." Journal of Chemical Research 2002, no. 8 (August 2002): 388–91. http://dx.doi.org/10.3184/030823402103172419.

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We report the preparation of 1-(1-alkenyl)benzotriazoles from alkenyl (phenyl)iodonium salts and benzotriazole. The reaction offers a simple and convenient route for the stereoselective synthesis of 1-(1-alkenyl)benzotriazoles. In addition, present method is particularly efficient for preparing 1-(1-alkenyl)benzotriazoles with amino-, acyl- and alkoxycarbonyl substituents, which were difficult to prepare by conventional methods.

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41

Furness, M. Scott, T. Philip Robinson, David J. Goldsmith, and J. Phillip Bowen. "An efficient synthesis of 2-aryl and 2-alkenyl-3-alkoxy-cyclohexenones by a modified Stille reaction." Tetrahedron Letters 40, no. 3 (January 1999): 459–62. http://dx.doi.org/10.1016/s0040-4039(98)02424-1.

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42

Belmont, James A., Jorge Soto, Roswell E. King, Andrew J. Donaldson, John D. Hewes, and M. Frederick Hawthorne. "Metallacarboranes in catalysis. 8. I: Catalytic hydrogenolysis of alkenyl acetates. II: Catalytic alkene isomerization and hydrogenation revisited." Journal of the American Chemical Society 111, no. 19 (September 1989): 7475–86. http://dx.doi.org/10.1021/ja00201a031.

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43

Rueda-Becerril, Montserrat, Joe C. T. Leung, Christine R. Dunbar, and Glenn M. Sammis. "Alkoxy Radical Cyclizations onto Silyl Enol Ethers Relative to Alkene Cyclization, Hydrogen Atom Transfer, and Fragmentation Reactions." Journal of Organic Chemistry 76, no. 19 (October 7, 2011): 7720–29. http://dx.doi.org/10.1021/jo200992m.

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44

VOIGT, K., U. SCHICK, F. E. MEYER, and A. DE MEIJERE. "ChemInform Abstract: Rate Enhancement of Palladium-Catalyzed Alkene to Alkenyl and Aryl Halide Couplings Under High Pressure." ChemInform 25, no. 35 (August 19, 2010): no. http://dx.doi.org/10.1002/chin.199435093.

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45

LAKSHMI, A. B., and J. M. RAO. "ChemInform Abstract: Intramolecular Cross-Ring Enone-Alkene Photoannelation in 6-(ω- Alkenyl)cyclohex-2-en-1-ones." ChemInform 22, no. 46 (August 22, 2010): no. http://dx.doi.org/10.1002/chin.199146142.

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46

Huynh, Lam K., Sylwester Panasewicz, Artur Ratkiewicz, and Thanh N. Truong. "Ab Initio Study on the Kinetics of Hydrogen Abstraction for the H + Alkene → H2+ Alkenyl Reaction Class." Journal of Physical Chemistry A 111, no. 11 (March 2007): 2156–65. http://dx.doi.org/10.1021/jp066659u.

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47

Dukomalamo, Irma, Meiske Sientje Sangi, and Johnly Alfreds Rorong. "Analisis Senyawa Toksik Tepung Pelepah Batang Aren (Arenga pinnata) dengan Spektroskopi UV-Vis dan Inframerah." Jurnal MIPA 4, no. 2 (May 6, 2015): 54. http://dx.doi.org/10.35799/jm.5.1.2016.12287.

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Telah dilakukan penelitian mengenai analisis senyawa toksik tepung pelepah batang aren (A. pinnata) dengan spektroskopi UV-Vis dan inframerah dengan tujuan untuk mengisolasi senyawa toksik dari tepung pelepah batang aren dan menganalisis senyawa toksik tersebut dengan spektroskopi UV-Vis dan inframerah. Tepung pelepah batang aren diekstraksi dengan cara maserasi menggunakan pelarut etanol hasil redestilasi cap tikus. Ekstrak diuji dengan Kromatografi Lapis Tipis (KLT) untuk menentukan jenis eluen terbaik untuk dipisahkan dengan kromatografi kolom sehingga diperoleh fraksi-fraksi. Fraksi hasil kromatografi kolom diuji KLT ulang, noda sama dari beberapa fraksi digabungkan. Fraksi yang hanya memiliki 1 noda dilakukan uji toksisitas dengan metode Brine Shrimp Lethality Test (BSLT) menggunakan larva udang Artemia salina L. dan dianalisis menggunakan spektroskopi UV-Vis dan inframerah. Hasil pengujian KLT diperoleh 6 noda dengan nilai Rf yaitu noda (a) 0,961; (b) 0,857; (c) 0,779; (d) 0,714; (e) 0,623; (f) 0,376. Fraksi A hasil kromatografi kolom dengan noda tunggal yang dilakukan uji KLT Rf = 0,961. Fraksi A yang diuji toksisitas menunjukkan fraksi bersifat toksik dengan nilai LC50 sebesar 269,15 ppm. Analisis spektrofotometer UV-Vis dan Inframerah menunjukkan bahwa fraksi memiliki gugus fungsi –C=O, -C-O ester, -C=C alkena, serta C-C dan C-H alkana. Dari hasil penelitian dapat disimpulkan bahwa senyawa yang diisolasi dari tepung pelepah batang aren bersifat toksik dengan nilai LC50 sebesar 269,15 ppm dan merupakan senyawa nonpolar yang memiliki gugus fungsi –C=O, -C-O ester, -C=C alkena, serta C-C dan C-H alkana.A research has been done about Analysis of Toxic Compounds Sugar Palm Stem Midrib Flour (A. Pinnata) using UV-Vis and Infrared Spectroscopy, aimed to isolated of toxic compounds sugar palm stem midrib flour and analyze using UV-Vis and infrared spectroscopy. Sugar palm stem midrib flour extracted by maceration using ethanol as solvent results from redistillation cap tikus. The extract was tested by Thin Layer Chromatography (TLC) to determine the best eluent for separated with column chromatography to obtained fractions. Fractions column chromatography results were tested using KLT, the same spot of fractions were combined. Fraction having 1 spot was toxicity test performed by the method of Brine Shrimp Lethality Test (BSLT) using Artemia salina L. larvae and analyze using UV-Vis and infrared spectroscopy. Results KLT testing obtained six spots with Rf is (a) 0,961; (b) 0,857; (c) 0,779; (d) 0,714; (e) 0,623; (f) 0,376. Fraction A column chromatography results having one spot by KLT test with Rf = 0,961. The results of toxicity test showed fraction A was toxic with LC50 269,15 ppm. Analysis spectrophotometer UV-Vis and inframerah showed that fraction had functional group like –C=O, -C-O esther, -C=C alkene, C-C and C-H alkane. This research concludes compound of sugar palm stem midrib flour isolated sugar palm stem midrib flour and nonpolar compound with functional group like –C=O, -C-O esther, -C=C alkene, C-C and C-H alkane.

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48

Schmid, George H., and James W. Gordon. "Influence of alkene structure on the formation constants of alkene–ICl molecular complexes." Canadian Journal of Chemistry 64, no. 11 (November 1, 1986): 2171–74. http://dx.doi.org/10.1139/v86-357.

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The experimentally determined rate law for the addition of ICl to 22 alkenes in CCl4 at 25 °C under conditions of (alkene)0 [Formula: see text] (ICl)0 is −d(ICl)/dt = kexp(alkene)0(ICl)3/{1 + C2(alkene)0}3. The constant C2 is shown to be equal to Kapp which is a measure of the formation constant or constants of the molecular complexes in this system. Under the experimental conditions used, C2 is a good approximation of the formation constant of the 1:1 alkene–ICl molecular complex. Thus the values of C2 obtained allow an estimate of the effect of alkene structure on the formation constant of the first molecular complex involved in this addition reaction. The contribution of the effect of substituents on C2 is estimated to be approximately 24% of the overall change in rate due to change in the alkene structure.

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49

Temnikov, M. N., N. V. Cherkun, K. L. Boldyrev, S. N. Zimovets, E. G. Kononova, I. V. Elmanovich, M. O. Gallyamov, and A. M. Muzafarov. "Interaction of organodialkoxysilanolates with carbon dioxide." RSC Advances 6, no. 107 (2016): 105161–65. http://dx.doi.org/10.1039/c6ra19758b.

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A series of organo(alkoxy)disiloxanes was obtained by the reaction of CO₂with sodium alkoxy(organo)silanolates under high pressure. It is suggested that the reaction involves intermediate formation of the carbonate derivative of sodium alkoxy(organo)silanolates.

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50

Wolf, Jeremy R. "Effect of Lateral Substitution on the Electronics and Phase Transitions of Stilbazoles, Benzoic Acids, Phenols, and Hydrogen Bonded Mixtures." Journal of Materials 2015 (October 7, 2015): 1–14. http://dx.doi.org/10.1155/2015/694729.

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The preparation and characterization of laterally substituted 4-alkoxy-stilbazoles, 4-alkoxy-benzoic acids, and 4-alkoxy phenols and hydrogen bonded heterodimeric mixtures of these compounds are reported. Lateral substitution has a minimal effect on the ring electronics of 4-alkoxy benzoic acids and 4-alkoxy phenols; however the ring electronics of stilbazole units is extremely sensitive to lateral substitution. While lateral substitution is an effective technique for lowering the melting points of both hydrogen bonded complexes and their individual components, its effect on the electronics of stilbazoles and steric disruption of both intermolecular hydrogen bonding and molecular packing in the solid state disrupts the formation of liquid crystalline phases in both the individual components and hydrogen bonded complexes.

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