655-48-1Relevant articles and documents
Stereospecific and regioselective reactions of silacyclopropanes with carbonyl compounds catalyzed by copper salts: Evidence for a transmetalation mechanism
Franz, Annaliese K.,Woerpel
, p. 949 - 957 (1999)
Silacyclopropanes reacted with carbonyl compounds under mild conditions (10 mol % metal salt, ≤22 °C) in a stereospecific and highly stereo-, regio-, and chemoselective fashion. In most cases, CuI or CuBr2 were the optimal catalysts although ZnBr2 worked comparably well in a few examples. Insertion occurred with retention of configuration and, in the case of enals and formamides, with high diastereoselectivity at the newly formed stereogenic centers. For unsymmetrical substrates, insertion occurred at the more substituted carbon-silicon bond with complete regioselectivity. Competition experiments demonstrated that formamides reacted faster than enals, which reacted faster than enoates; saturated aldehydes did not undergo insertion. With a cis-disubstituted silacyclopropane, products of silylene transfer were observed. The stereochemistry, regiochemistry, and chemoselectivity of carbonyl insertion as well as the silylene transfer processes can be explained by a mechanism involving transmetalation of silicon to copper.
Metal-free thermal organocatalytic pinacol coupling of arylaldehydes using an isonicotinate catalyst with bis(pinacolato)diboron
Hanaya, Kengo,Higashibayashi, Shuhei,Sugai, Takeshi,Yasui, Masamichi
, p. 24652 - 24655 (2021/07/29)
The metal-free thermal organocatalytic pinacol coupling of arylaldehydes has been developed. The intermolecular coupling of arylaldehydes catalyzed byt-butyl isonicotinate with bis(pinacolato)diboron as the co-reducing agent afforded 1,2-diphenylethane-1,2-diols. This reaction was also applicable to the intramolecular coupling of 1,1′-biphenyl-2,2′-dicarbaldehydes to afford 9,10-dihydrophenanthrene-9,10-diols. Various functional groups were tolerated under this coupling condition.
Electrochemical Arylation of Aldehydes, Ketones, and Alcohols: from Cathodic Reduction to Convergent Paired Electrolysis
Zhang, Sheng,Li, Lijun,Li, Jingjing,Shi, Jianxue,Xu, Kun,Gao, Wenchao,Zong, Luyi,Li, Guigen,Findlater, Michael
supporting information, p. 7275 - 7282 (2021/03/01)
Arylation of carbonyls, one of the most common approaches toward alcohols, has received tremendous attention, as alcohols are important feedstocks and building blocks in organic synthesis. Despite great progress, there is still a great gap to develop an ideal arylation method featuring mild conditions, good functional group tolerance, and readily available starting materials. We now show that electrochemical arylation can fill the gap. By taking advantage of synthetic electrochemistry, commercially available aldehydes (ketones) and benzylic alcohols can be readily arylated to provide a general and scalable access to structurally diverse alcohols (97 examples, >10 gram-scale). More importantly, convergent paired electrolysis, the ideal but challenging electrochemical technology, was employed to transform low-value alcohols into more useful alcohols. Detailed mechanism study suggests that two plausible pathways are involved in the redox neutral α-arylation of benzylic alcohols.
