66292-25-9Relevant academic research and scientific papers
Alkene homologation: via visible light promoted hydrophosphination using triphenylphosphonium triflate
Levin, Vitalij V.,Dilman, Alexander D.
supporting information, p. 749 - 752 (2021/02/03)
A hydrophosphination reaction of alkenes with triphenylphosphonium triflate under photocatalytic conditions is described. The reaction is promoted by naphthalene-fused N-acylbenzimidazole and is believed to proceed through intermediate formation of a phosphinyl radical cation. The resulting phosphonium salts are directly involved in the Wittig reaction leading to homologated alkenes.
Alkenylation of unactivated alkyl bromides through visible light photocatalysis
Zhou, Quan-Quan,Düsel, Simon Josef Siegfried,Lu, Liang-Qiu,K?nig, Burkhard,Xiao, Wen-Jing
supporting information, p. 107 - 110 (2019/01/03)
Two visible-light driven alkenylation reactions of unactivated alkyl bromides, which were enabled by the use of Ir(dF(CF3)ppy)2(dtbbpy)PF6 as the photocatalyst and (TMS)3SiH as the atom transfer reagent to activate the alkyl bromides, were described for the first time. These protocols can be used to produce a variety of alkenes from easily available feedstock with good reaction efficiency and high chemoselectivity under mild reaction conditions. To further demonstrate the applicability of the present strategy, the alkenylation of bioactive molecules and glycosyl bromides, as well as the alkynylation of unactivated alkyl bromides, was proven to be feasible.
Photo-induced Decarboxylative Heck-Type Coupling of Unactivated Aliphatic Acids and Terminal Alkenes in the Absence of Sacrificial Hydrogen Acceptors
Cao, Hui,Jiang, Heming,Feng, Hongyu,Kwan, Jeric Mun Chung,Liu, Xiaogang,Wu, Jie
supporting information, p. 16360 - 16367 (2018/11/27)
1,2-Disubstituted alkenes such as vinyl arenes, vinyl silanes, and vinyl boronates are among the most versatile building blocks that can be found in every sector of chemical science. We herein report a noble-metal-free method of accessing such olefins through a photo-induced decarboxylative Heck-type coupling using alkyl carboxylic acids, one of the most ubiquitous building blocks, as the feedstocks. This transformation was achieved in the absence of external oxidants through the synergistic combination of an organo photo-redox catalyst and a cobaloxime catalyst, with H2 and CO2 as the only byproducts. Both control experiments and DFT calculations supported a radical-based mechanism, which eventually led to the development of a selective three-component coupling of aliphatic carboxylic acids, acrylates, and vinyl arenes. More than 90 olefins across a wide range of functionalities were effectively synthesized with this simple protocol.
Silaheterocycles, XXIII. - Synthesis and Thermolysis Reactions of Si-Functionalized 2-Silaazetidines
Auner, Norbert,Weingartner, Armin W.,Bertrand, Guy
, p. 581 - 590 (2007/10/02)
Dichloroneopentylsilene (1) is formed in situ by the reaction of trichlorovinylsilane with LitBu.The cycloaddition to imines yields Si,Si-dichloro-functionalized 2-silaazetidines in a preparative scale.With aldimines as trapping agents for 1, the resulting SiN four-membered ring compounds are isolated as syn/anti-isomers (e.g. syn/anti-15 and -16; syn/anti ca. 2:1).Silene 1 is not liberated from the silaazetidines on heating, but the Si,Si-dichloro-substituted silanimine Cl2Si=NtBu (24) is formed.This can be trapped by Me3SiOMe or Ph2C=NtBu to give the addition products 25 and 26, respectively.The pathways are discussed which lead to stereoisomeric SiN ring compounds by a multiple-step mechanism including zwitterionic intermediates (1,4-dipoles).In addition there is strong evidence for the formation of 1, depending on the trapping reagent used.This fact may be explained by donor->silene interactions.The thermolysis products of silaazetidines support the formulation of a stepwise decomposition to an alkene and Cl2Si=NR derivatives. Key Words: Silene, dichloroneopentyl- / Imines / Cycloaddition reactions / 2-Silaazetidines / Thermolysis reactions
Electron-transfer processes. 43. Attack of alkyl radicals upon 1-alkenyl and 1-alkynyl derivatives of tin and mercury
Russell, Glen A.,Ngoviwatchai, Preecha,Tashtoush, Hasan I.
, p. 696 - 702 (2008/10/08)
Alkyl radicals, obtained by reaction of Bu3Sn? or ClHg? with alkylmercury halides, will undergo regioselective and in some cases stereospecific substitution by a free radical chain addition-elimination mechanism with 1-alkenylstannanes or -mercurials. The chain reaction is also observed for 1-alkynyl derivatives and in the photostimulated demercuration of mixed alkyl and 1-alkenyl- or 1-alkynylmercurials. Chain propagation with alkyl radical formation is also observed to occur in the reactions of β-eliminated ClHg? with Grignard reagents in PhH-THF solution. In competitive reactions of Bu3Sn? or ClHg? with pairs of alkylmercury chlorides, it is observed that a tert-butylmercurial is >1000 times more reactive than a n-butylmercurial, suggesting a concerted dissociate electron-transfer process not involving the intermediacy of RHg? species.
Reaction of Phenyl-Substituted Allyllithiums with tert-Alkyl Bromides. Remarkable Difference in the Alkylation Regiochemistry between a Polar Process and the One Involving Single-Electron Transfer
Tanaka, Jiro,Nojima, Masatomo,Kusabayashi, Shigekazu
, p. 3391 - 3397 (2007/10/02)
The reaction of phenyl-substituted allyllithiums 1a-h with tert-alkyl bromides was investigated systematically.The alkylation regiochemistry was influenced in a complicated fashion by various factors including substituent effects, both steric and electronic, solvents, and the presence of strongly coordinating additives, tetramethylethylenediamine and hexamethylphosphoramide.On the basis of the cyclizable probe experiments, the observed regiochemistry was interpreted as follows. (a) The reaction proceeds by two alternative pathways, a polar one and single electron transfer (SET), the extent of each path being influenced by the variable factors and (b) a polar pathway favors coupling at the phenyl-substituted site (C-1), while in the case of SET the C-C bond formation occurs predominantly at the site far from the phenyl substituent (C-3).
