Facile coupling of propargylic, allylic and benzylic alcohols with allylsilane and alkynylsilane, and their deoxygenation with Et3SiH, catalyzed by Bi(OTf)3 in [BMIM][BF4] ionic liquid (IL), with recycling and reuse of the IL
作者:G. G. K. S. Narayana Kumar、Kenneth K. Laali
DOI:10.1039/c2ob26046h
日期:——
substituted propargylicalcohol 1e with allyl-TMS gave the skeletally intact 1,5-enyne and a ring opened derivative as a mixture. Coupling of propargylic/allylic alcohol 1f with allyl-TMS resulted in allylation at both benzylic (2 isomers) and propargylic positions, as major and minor products respectively. The scope of this methodology for allylation of a series of allylic and benzylic alcohols was explored
Copper-Catalyzed Regioselective and Stereoselective Coupling of Grignard Reagents with Pent-1-en-4-yn-3-yl Benzoates: A Shortcut to (<i>Z</i>)<i>-</i>1,5-Disubstituted Pent-3-en-1-ynes from Accessible Starting Materials
Copper-catalyzed coupling of Grignardreagents with pent-1-en-4-yn-3-yl benzoates occurs regioselectively at the terminal alkenyl carbon rather than the alkynyl site, leading to the stereoselective formation of unexpected (Z)-1,5-disubstituted pent-3-en-1-ynes without generation of the initially expected alkenyl allene products. By using easily accessible starting materials, this reaction can provide
Synthesis of 1,5-diphenylpent-3-en-1-yne derivatives utilizing an aqueous B-alkyl Suzuki cross coupling reaction
作者:Da-Wei Chuang、Mohamed El-Shazly、Chin-Chau Chen、Yu-Ming Chung、Balaji D. Barve、Ming-Jung Wu、Fang-Rong Chang、Yang-Chang Wu
DOI:10.1016/j.tetlet.2013.07.020
日期:2013.9
1,5-Diphenylpent-3-en-1-yne derivatives were isolated in minor quantities from terrestrial plants and exhibited strong anti-inflammatory activity. A cross coupling reaction between B-benzyl-9-BBN and chloroenynes under mild condition was developed resulting in the formation of different 1,5-diphenylpent-3-en-1-yne derivatives with a full control on the E/Z selectivity. Several substrates bearing electron-donating
The conjugated (Z)-enynes 2a, 2d–g and (Z)-enediynes 2h–j were synthesized by dehydration of prop-2-ynyl alcohols 1a, 1d–j with polyphosphoric acid trimethysilyl ester.