Patent ID: 7214807
Filing Date: 2007-05-08
Classification: C07C,C07J

Abstract:
1. A method for the preparation of a compound of formula (7) wherein the symbol represents a single bond or a double bond; one of R 1 or R 2 is hydrogen and the other is optionally protected hydroxyl; or R 1 and R 2 together are oxo; R 3 and R 4 are independently hydrogen or halide; and R 5 and R 6 are independently C 1 –C 6 alkyl; the method comprising: (c) reacting a compound of formula (3) and a first base, an iodide salt, and the compound of formula (4) to provide a compound of formula (5) (d) reacting the product of step (c) and NaSH to provide a compound of formula (6) (e) reacting the product of step (d) and acid; (f) reacting the product of step (e) and chlorofluoromethane optionally in the presence of a second base; and (g) optionally deprotecting the product of step (f).