Rhodium-Catalyzed Asymmetric Cyclization/Hydroboration of 1,6-Enynes
作者:Robert E. Kinder、Ross A. Widenhoefer
DOI:10.1021/ol052986t
日期:2006.5.1
[reaction: see text] Reaction of enyne 1 with catecholborane catalyzed by a 1:1 mixture of [Rh(COD)(2)](+)SbF(6)(-) and (S)-BINAP (5 mol %) followed by Pd-catalyzed arylation with p-IC(6)H(4)CF(3) gave benzylidenecyclopentane 5 in 65% yield with 88% ee. Rhodium-catalyzed asymmetric cyclization/hydroboration followed either by Pd-catalyzed arylation or by oxidation was applied to the synthesis of a
Enantioselective Cyclization/Hydrosilylation of 1,6-Enynes Catalyzed by a Cationic Rhodium Bis(phosphine) Complex
作者:Harinath Chakrapani、Cong Liu、Ross A. Widenhoefer
DOI:10.1021/ol027196n
日期:2003.1.1
[reaction: see text] Reaction of 4,4-dicarbomethoxy-1-octene-6-yne (1) with triethylsilane and a catalytic 1:1 mixture of [Rh(COD)(2)](+) SbF(6)(-) and (R)-BIPHEMP (5 mol %) at 70 degrees C for 90 min gave (Z)-1,1-dicarbomethoxy-3-(1-triethylsilyl)ethylidene-4-methylcyclopentane (2) in 81% isolated yield with 98% de and 92% ee.