The esterification of sterically hindered or non-nucleophilic alcohols may often be problematic. The reaction of alcohols with acid fluorides is reported to be superior to standard acid activation protocols frequently used for difficult esterifications. The acid fluoride methodology was used to produce a hindered linkage between a secondary alcohol (4) and a cyclohexyl amino acid 3, a key intermediate in the formation of a constrained ring didemnin analog.
Synthesis of unsaturated hydroxy acids by the cobalt carbonyl and phase transfer catalyzed carbonylation of vinyl epoxides
作者:Howard Alper、Serge Calet
DOI:10.1016/s0040-4039(00)82036-5
日期:1988.1
Phase transfer catalyzedreaction of vinyl epoxides with carbonmonoxide, methyl iodide, catalytic amounts of cobaltcarbonyl and TDA-1, affords β-hydroxy acids. High regioselectivity was observed in some cases.