BROWN D. W.; CAMPBELL M. M.; TAYLOR A. P.; ZHANG XIAO-AN, TETRAHEDRON LETT., 28,(1987) N 9, 985-988
作者:BROWN D. W.、 CAMPBELL M. M.、 TAYLOR A. P.、 ZHANG XIAO-AN
DOI:——
日期:——
Stereoselective synthesis of freelingyne and related γ-alkylidenebutenolides via vinylogous Mukaiyama aldol additions
作者:Frank von der Ohe、Reinhard Brückner
DOI:10.1039/b002903n
日期:——
Following the strategy of Scheme 1, a Mukaiyama aldoladdition/anti-elimination route to stereopure γ-alkylidenebutenolides 4 was established. The addition giving 27 was only moderately diastereoselective but the products lk- and ul-27 were chromatographically separable (Scheme 4). They underwent highly selective anti-eliminations in the presence of triflic anhydride–pyridine or Burgess' reagent, furnishing