Abstract
Cis- or trans-7-chloro-7,8,9,10-tetrahydrobenzo[a]pyrene-8-ol were prepared from the corresponding epoxide in good selectivity and yield via LiCl hydrochlorination in different solvents. These preparations take advantage of a dramatic solvent effect on the hydrochlorination diastereoselectivity. Cis products strongly predominate in chlorinated hydrocarbons, and alternatively, trans chlorohydrin formation occurs in high selectivity in Et2O, THF, and acetone. This solvent effect was not significant for other halide salts.
Acknowledgment
This work was supported by grants from The Welch Foundation (#96-086) and NIGMS (S06 GM08194). We thank Justin King, Roberto Alcorta, and Dr. Larry Ytuarte for technical support.