Methanol → 6-Bromo-3,4-dihydro-2H-1-benzopyran-2-methanol

Participants

Reaction Steps

To a stirred mixture of 80 parts of 6-bromo-3,4-dihydro-2H-benzopyran-2-carboxylic acid and 225 parts of tetrahydrofuran were added dropwise 400 parts of a solution of borane, compound with thiobismethane 0.2N in tetrahydrofuran. Upon completion, stirring was continued for 4hours at room temperature. 80 parts of methanol were added dropwise and stirring was continued for 30 minutes at reflux temperature. The solvent was distilled off till half its volume. The remaining solvent was evaporated and the residue was distilled, yielding 63 parts (86%) of 6-bromo-3,4-dihydro-2H-1-benzopyran-2-methanol; bp. 150° C. at 39.9 Pa (intermediate 1).

Provenance & Evidence