Effect of a proximal oxygen substituent on the efficacy of ruthenium-catalyzed cross-metathesis and RCM
摘要:
Ruthenium-catalyzed cross-metathesis of various derivatives of 1,2-dihydroxy-3-butene reveals that cyclic acetals are best suited as substrates compared to acyclic diethers or diacetates, while RCM is relatively insensitive to the presence of allylic or homoallylic hydroxy or acetoxy groups. (C) 2002 Elsevier Science Ltd. All rights reserved.
Asymmetric Total Syntheses of (−)-Antofine and (−)-Cryptopleurine Using (<i>R</i>)-(<i>E</i>)-4-(Tributylstannyl)but-3-en-2-ol
作者:Sanghee Kim、Taeho Lee、Eunjung Lee、Jaekwang Lee、Gao-jun Fan、Sang Kook Lee、Deukjoon Kim
DOI:10.1021/jo049820a
日期:2004.4.1
The asymmetric total syntheses of the representative phenanthroindolizidine and phenanthroquinolizidine alkaloids, (−)-antofine and (−)-cryptopleurine, are described. An efficient synthetic pathway to the key intermediate 12, in enantiomerically pure form, was achieved by using a chiral building block (R)-9 and the Overman rearrangement with a total transfer of chirality. The problem of constructing