The Alder-Rickert Reaction in a Synthesis of m-Chlorophenols and 4-Chloromycophenolic Acid
摘要:
A new synthesis of highly substituted m-chlorophenols 12 using the Alder-Rickert reaction between 1-chloro-3-(trimethylsiloxy)-1,3-cyclohexadienes 10 and activated acetylenes has been devised. This sequence has been shown to be highly regioselective when methyl propiolate is the dienophile, and the methodology has been adapted to a facile preparation of 4-chloromycophenolic acid (23).
Resolution of trans-1,2-dihydroxy-1,2-dihydrobenzene for the preparation of optically pure benzene diol epoxides. Preparation of bromo- and chlorobenzene diol epoxides