Synthesis of Stereopentad Analogues of the C14−C22 Segment of Callystatin A through Additions of Chiral Allenylzinc Reagents to Stereotriads
作者:James A. Marshall、Gregory M. Schaaf
DOI:10.1021/jo015936k
日期:2001.11.1
The addition of (P)- and (M)-allenylzinc reagents, prepared in situ through Pd-catalyzed metalation of (R)- and (S)-3-butyn-2-ol mesylates, to diastereomeric stereotriad aldehydes 8, 13, 18, and 23 of syn,syn, syn,anti, anti,anti, and anti,syn stereochemistry was examined. Additions to the former two aldehydes afforded the four anti adducts with high diastereoselectivity and negligible mismatching