Synthesis of acetylenic alcohols with calcium carbide as the acetylene source
作者:Yin Ngai Sum、Dingyi Yu、Yugen Zhang
DOI:10.1039/c3gc41269e
日期:——
Propargyl alcohols containing a terminal alkyne group are highly important and versatile intermediates. Here, we report the synthesis of these compounds from an inexpensive and renewable resource, calcium carbide (CaC2). No metal catalysts are required in this new protocol and the reactions take place under very mild conditions.
Treatment of benzyl γ-(trimethylsilyl)propargyl ether with n-BuLi is shown to afford the rarely precedent ortho-[2,3]-Wittig product in remarkable preference to the [1,2]-Wittig product. The factors governing the periselectivity in this type of carbanion rearrangement are discussed.
Guillerm-Dron,D. et al., Bulletin de la Societe Chimique de France, 1973, p. 1417 - 1423
作者:Guillerm-Dron,D. et al.
DOI:——
日期:——
US4983627A
申请人:——
公开号:US4983627A
公开(公告)日:1991-01-08
Fluoride-Assisted Activation of Calcium Carbide: A Simple Method for the Ethynylation of Aldehydes and Ketones
作者:Abolfazl Hosseini、Daniel Seidel、Andreas Miska、Peter R. Schreiner
DOI:10.1021/acs.orglett.5b01219
日期:2015.6.5
The fluoride-assisted ethynylation of ketones and aldehydes is described using commercially available calcium carbide with typically 5 mol % of TBAF·3H2O as the catalyst in DMSO. Activation of calcium carbide by fluoride is thought to generate an acetylide “ate”-complex that readily adds to carbonyl groups. Aliphatic aldehydes and ketones generally provide high yields, whereas aromatic carbonyls afford