18317-64-1Relevant articles and documents
The Synthesis and Chemistry of 8-Substituted Bicyclo[5.1.0]oct-1(8)-ene
Lee, Gon-Ann,Chen, Calvin Ping-Kuang,Chen, Mei-Yun
, p. 381 - 385 (1998)
8-Bromobicyclo[5.1.0]oct-1(8)-ene (7), an intermediate for the preparation of 8-substituted bicyclo[5.1.0]oct-1(8)-enes, was synthesized by debromination of 1,8,8-tribromobicyclo[5.1.0]octane (6). Compound 7 underwent bromo-lithium exchange followed by nucleophilic substitution reactions to generate bicyclo[5.1.0]oct-1(8)-ene (5), 8-methylbicyclo[5.1.0]oct-1(8)-ene (10), and 8-trimethylsilylbicyclo[5.1.0]oct-1(8)-ene (11). The bicyclic cyclopropenes 7, 5, 10, and 11 reacted with cyclopentadiene to form adducts 12, 13, 14, and 15, respectively. All of these Diels-Alderadducts are endo-exo isomers (endo-addition from the view of the cyclopropene and exo-addition from the view of the cyclooctene).
Regio- and stereoselectivity of ene eeactions: The dimerization of bicyclic 1,3-fused 2-(trimethylsilyl)cycloprop-1-enes
Ko, Chou Chen,Wen, Chieh Wang,Chen, Mei-Yun,Chen, Wei-G,Her, Ming-Chieh,Lee, Gon-Ann
, p. 953 - 958 (2007)
Cycloalkenes proceed through bromination, dehydrobromination and dibromocarbene addition reactions to give tribromocyclopropanes 10 and 11. The treatment of tribromocyclopropanes 10 and 11 with 3 equiv. of methyllithium in diethyl ether at -78°C followed by treatment with trimethylsilyl chloride produce 8-(trimethylsilyl)bicyclo[5.1.0]oct-1(8)-ene (4) and 9-(trimethylsilyl)bicyclo[6.1.0]non-1(9)-ene (5). Both 4 and 5 undergo ene dimerization via the same steric isomer and an endo transition state to generate the stable adducts 6 and 7, respectively, as the sole isomers. Compound 6, containing an unstable bicyclo[5.1.0]oct-1(8)-enyl group and produced in high yields, has been reported to be an unstable species. Both of the ene dimers, (trimethylsilyl)cyclopropenes 6 and 7, can be converted into cyclopropenes 8 and 9 by treatment with a fluoride salt followed by protonation. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
Copper-Catalyzed C?P Cross-Coupling of (Cyclo)alkenyl/Aryl Bromides and Secondary Phosphine Oxides with in situ Halogen Exchange
Stankevi?, Marek,Wo?nicki, Pawe?
supporting information, p. 3484 - 3491 (2021/07/22)
An efficient protocol for concurrent tandem halogen exchange/C?P cross-coupling of cycloalkenyl bromides and secondary phosphine oxides has been developed. The catalytic system is based on cheap and air-stable copper(I) iodide as the precatalyst, commercially available N,N’-dimethylethylenediamine as the ligand, and Cs2CO3 or K2CO3 as the base. The use of sodium iodide as an additive reduces the excessive use of organic bromides to near-stoichiometric by promoting the in situ transformation to the corresponding iodides. Diarylphosphine oxides undergo cycloalkenylation with 35–99 % yields and dicyclohexylphosphine oxide with 30–53 % yields. In the case of acyclic alkenyl bromides the cross-coupling products undergo conjugate addition of diphenylphosphine oxide and satisfying yields are observed only for internal olefins. In the case of aryl bromides satisfying yields (43–72 %) are observed only for sterically unhindered arenes or arenes possessing an ortho-directing group. Cycloalkenylphosphine oxides prepared in the cross-coupling reaction undergo base-catalyzed and base-promoted conjugate addition to give bis(phosphinoyl)cycloalkanes.
Cyclic Alkenylsulfonyl Fluorides: Palladium-Catalyzed Synthesis and Functionalization of Compact Multifunctional Reagents
Lou, Terry Shing-Bong,Bagley, Scott W.,Willis, Michael C.
supporting information, p. 18859 - 18863 (2019/11/19)
A series of low-molecular-weight, compact, and multifunctional cyclic alkenylsulfonyl fluorides were efficiently prepared from the corresponding alkenyl triflates. Palladium-catalyzed sulfur dioxide insertion using the surrogate reagent DABSO effects sulfinate formation, before trapping with an F electrophile delivers the sulfonyl fluorides. A broad range of functional groups are tolerated, and a correspondingly large collection of derivatization reactions are possible on the products, including substitution at sulfur, conjugate addition, and N-functionalization. Together, these attributes suggest that this method could find new applications in chemical biology.
Iodine(III)-Mediated Oxidative Hydrolysis of Haloalkenes: Access to α-Halo Ketones by a Release-and-Catch Mechanism
Jobin-Des Lauriers, Antoine,Legault, Claude Y.
supporting information, p. 108 - 111 (2016/01/15)
An unprecedented iodine(III)-mediated oxidative transposition of vinyl halides has been accomplished. The products obtained, α-halo ketones, are useful and polyvalent synthetic precursors. There are only a handful of reported examples of the direct conversion of vinyl halides to their corresponding α-halo carbonyl compounds. Insights into the mechanism and demonstration that this synthetic transformation can be done under enantioselective conditions are reported.
Formation of enehydrazine intermediates through coupling of phenylhydrazines with vinyl halides: Entry into the Fischer indole synthesis
Zhan, Fuxu,Liang, Guangxin
supporting information, p. 1266 - 1269 (2013/03/13)
Cut to the chase: Direct formation of an enehydrazine, an intermediate in the classic Fischer indole synthesis, solves the regioselectivity problem associated with indolization. This approach not only achieves selective synthesis of indoles through proper selection of the vinyl halide, but also leads to quick construction of desoxyeseroline and esermethole, as well as the key structural motif in the Akuammiline alkaloid vincorine. Copyright
Some reactions of gem-dibromocyclopropanes and metal carbonyls
Lin, Shaw-Tao,Lee, Chuan-Chen,Ding, Mei-Fang,Liang, David W.,Jeng, An-Ting
scheme or table, p. 529 - 534 (2012/08/08)
A series of gem-dibromocyclopropanes were treated with various metal complexes. Among the metal complexes, Ru(CO)2(PPh3) 3, Ru(CO)3(PPh3)2, and Mo(CO) 6 were able to remove a bro
Ruthenium-catalyzed transformation of alkenyl triflates to alkenyl halides
Shirakawa, Eiji,Imazaki, Yusuke,Hayashi, Tamio
supporting information; experimental part, p. 5088 - 5090 (2009/12/08)
In the presence of a ruthenium catalyst, alkenyl triflates were found to be transformed to the corresponding bromides, chlorides and iodides simply by treatment with a lithium halide (1.2 equiv.). The Royal Society of Chemistry 2009.
Method to inhibit ethylene responses in plants
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Page/Page column 6, (2008/06/13)
The present invention generally relates to methods of inhibiting ethylene responses in plants and plant materials, and particularly relates to methods of inhibiting various ethylene responses including plant maturation and degradation, by exposing plants
A METHOD TO INHIBIT ETHYLENE RESPONSES IN PLANTS
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Page/Page column 9, (2008/06/13)
The present invention generally relates to methods of inhibiting ethylene responses in plants and plant materials, and particularly relates to methods of inhibiting various ethylene responses including plant maturation and degradation, by exposing plants
