Stereoselective construction of 3a-methylhydrindanes starting from 2,7-enynol derivatives based on Ti(II)-mediated cyclization and Ru-catalyzed ring-closing metathesis
摘要:
The Ti(II)-mediated cyclization of 3-methyloct-2-en-7-yn-l-ol derivatives 2 proceeded stereoselectively to afford 1-methyl-2-(1-alkylbut-3-enylidene)-1-vinylcyclopentanes 3 after treatment of the resulting alkenyltitaniums with allylbromide in the presence of CuCN, which was readily converted to 3a-methyl-2,3,3a,6-tetrahydro-1H-indenes 1 by the Ru-catalyzed ring-closing metathesis. (c) 2006 Elsevier Ltd. All rights reserved.
Total Synthesis of (±)-Merrilactone A via Catalytic Nazarov Cyclization
作者:Wei He、Jie Huang、Xiufeng Sun、Alison J. Frontier
DOI:10.1021/ja068150i
日期:2007.1.1
The totalsynthesis of merrilactone A (a neurotrophic agent) has been achieved. In the approach reported, simultaneous creation of the C-4 and C-5 stereocenters was accomplished stereospecifically using an unprecedented variant of the Nazarov cyclization. Additional studies focused upon this Lewis acid-catalyzed cyclization of a silyloxyfuran-containing intermediate are presented.