Synthesis of Unsymmetrically Substituted 1,3-Butadiynes and 1,3,5-Hexatriynes via Alkylidene Carbenoid Rearrangements
作者:Annabelle L. K. Shi Shun、Erin T. Chernick、Sara Eisler、Rik R. Tykwinski
DOI:10.1021/jo026481h
日期:2003.2.1
Unsymmetrically substituted 1,3-butadiynes and 1,3,5-hexatriynes are synthesized in four steps from commercially available aldehydes or carboxylic acids. The key step in this process involves a Fritsch-Buttenberg-Wiechell rearrangement, in which an alkylidene carbenoid intermediate subsequently rearranges to the desired polyyne. This rearrangement proceeds under mild conditions, and it is tolerant
A fine addition! A highlyenantioselective and efficient procedure for the amino‐alcohol–zinc‐catalyzedaddition of trimethylsilylacetylene to aromatic, α,β‐unsaturated, and aliphatic aldehydes has been developed (see scheme; R=aryl, alkynyl, or alkyl; TMS=trimethylsilyl; TBDMS=tert‐butyldimethylsilyl). The present protocol was successfully applied in the concise synthesis of the natural products marine
很好的补充!已开发出一种高度对映选择性和高效的程序,用于氨基醇锌催化的三甲基甲硅烷基乙炔加成到芳族,α,β-不饱和和脂肪族醛中(见方案; R =芳基,炔基或烷基; TMS =三甲基甲硅烷基; TBDMS =叔丁基二甲基甲硅烷基)。本协议已成功地应用于天然产物海洋炔醇和法卡林二醇的简明合成中。
Modification of the Fritsch–Buttenberg–Wiechell rearrangement: a facile route to unsymmetrical butadiynes
作者:Erin T Chernick、Sara Eisler、Rik R Tykwinski
DOI:10.1016/s0040-4039(01)01901-3
日期:2001.12
echell rearrangement has been used to form unsymmetrically substituted 1,3-butadiynes from 1,1-dibromo-olefin precursors. The reaction proceeds via lithium–halogen exchange, followed by migration of the aryl or alkynyl moiety to provide the butadiyne framework. The facile formation of the dibromo-olefins in three steps from commercially available aryl aldehydes or carboxylic acid chlorides makes this
Iron-Catalyzed C−O Bond Activation for the Synthesis of Propargyl-1,2,3-triazoles and 1,1-Bis-triazoles
作者:Wuming Yan、Qiaoyi Wang、Yunfeng Chen、Jeffrey L. Petersen、Xiaodong Shi
DOI:10.1021/ol101082v
日期:2010.8.6
The FeCl(3)-catalyzed triazole propargylation was developed. This transformation was suitable for a large scope of substituted propargyl alcohols, giving the corresponding propargyl triazoles In excellent yields (up to 96%). Further derivatization produced the 1,1-bis-triazoles in excellent yields and regioselectivity, which could be applied as potential transition metal ligands or new reagents.