695-12-5Relevant articles and documents
Contra-thermodynamic Olefin Isomerization by Chain-Walking Hydroboration and Dehydroboration
Bloomer, Brandon,Butcher, Trevor W.,Ciccia, Nicodemo R.,Conk, Richard J.,Hanna, Steven,Hartwig, John F.
, p. 1005 - 1010 (2022/02/10)
We report a dehydroboration process that can be coupled with chain-walking hydroboration to create a one-pot, contra-thermodynamic, short-or long-range isomerization of internal olefins to terminal olefins. This dehydroboration occurs by a sequence comprising activation with a nucleophile, iodination, and base-promoted elimination. The isomerization proceeds at room temperature without the need for a fluoride base, and the substrate scope of this isomerization is expanded over those of previous isomerizations we have reported with silanes.
Preparation method of vinylcyclohexane
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Paragraph 0028-0039, (2021/04/29)
The invention discloses a preparation method of vinylcyclohexane, and belongs to the technical field of organic synthesis. Cyclohexyl ketone is used as a raw material, and is firstly condensed with 2, 4, 6-triisopropylbenzenesulfonyl hydrazide to obtain 1-acetocyclohexane-2, 4, 6-triisopropylbenzenesulfonyl hydrazone; and reaction is carried out in the presence of an inorganic base and a non-nucleophilic strong base to obtain vinylcyclohexane. The method has the advantages of two-step reaction, simple route, high area selection and relatively easy product separation, and a certain amount of polymerization inhibitor needs to be added in the product distillation process to prevent polymerization in the distillation process.
An Annelated Mesoionic Carbene (MIC) Based Ru(II) Catalyst for Chemo- And Stereoselective Semihydrogenation of Internal and Terminal Alkynes
Bera, Jitendra K.,Choudhury, Joyanta,Das, Shubhajit,Dutta, Indranil,Pati, Swapan K.,Saha, Sayantani,Yadav, Suman
, p. 3212 - 3223 (2020/10/02)
The catalytic utility of [RuL1(CO)2I2] (1), containing an annelated π-conjugated imidazo-naphthyridine-based mesoionic carbene (MIC) ligand (L1), is evaluated for E-selective alkyne semihydrogenation. The precatalyst 1, in combination with 2 equiv of AgBArF, semihydrogenates a broad range of internal alkynes with molecular hydrogen (5 bar) in water. (E)-Alkenes are accessed in high yields, and a number of reducible functional groups are tolerated. A chelate MIC ligand and two cis carbonyls provide a well-defined platform at the Ru center for hydrogenation and isomerization. The loss of two iodides and the presence of two carbonyls render the Ru center electron deficient and thus the formation of metal vinylidenes with terminal alkynes is avoided. This is leveraged for the semihydrogenation of terminal alkynes by the same catalytic system in isopropyl alcohol. Reaction profile, isomerization, kinetic, and DFT studies reveal initial alkyne hydrogenation to a (Z)-alkene, which further isomerizes to an (E)-alkene via metal-catalyzed Z → E isomerization.