METHOD FOR PRODUCING VITAMIN D ANALOG COMPOUND

摘要

PROBLEM TO BE SOLVED: To provide a stereospecific method for producing a vitamin D analog compound. SOLUTION: This stereospecific method for obtaining a compound of formula 2 having the same stereochemistry as that of a compound of formula 2 in both a carbon atom at the 1-position and a carbon atom at the 3-position comprises carrying out the following reaction. The compound of formula 1 is reacted with a fluorinated alcohol having pKa lower than about 9 in the presence of a palladium catalyst. In the formula, R1 is a 1-6C alkyl and R2 is a hydroxy- protecting group.