Synthetic Routes to Allenic Acids and Esters and Their Stereospecific Conversion to Butenolides
作者:James A. Marshall、Mark A. Wolf、Eli M. Wallace
DOI:10.1021/jo9618740
日期:1997.1.1
19 and 23 with inversion of configuration through treatment with Pd(Ph(3)P)(4), CO, and the appropriate alcohol in THF. These reactions proceeded with ca. 10% or less of racemization. The allenic esters 23 yielded the iodobutenolides 24 by reaction with IBr. Hydrogenolysis to the butenolide 25 was achieved with Pd(PPh(3))(4) and Bu(3)SnH. Alternatively, the allenic acids 27 could be prepared directly