Synthesis of 24-phenyl-24-oxo steroids derived from bile acids by palladium-catalyzed cross coupling with phenylboronic acid. NMR characterization and X-ray structures

• Reaction of bile acids and phenylboronic acid led to 24-phenyl-24-oxo steroids.
• Moderate to good yields of 24-phenyl-24-oxo steroids were obtained.
• This one-pot procedure avoids the preparation and manipulation of acyl chlorides.
• X-ray and NMR allowed the unambiguous characterization.

Palladium-catalyzed cross coupling of phenyboronic acid with acetylated bile acids in which the carboxyl functions have been activated by formation of a mixed anhydride with pivalic anhydride afforded moderate to good yield of 24-phenyl-24-oxo-steroids. Unambiguous assignments of the NMR signals were made with the aid of combined 1D and 2D NMR techniques. X-ray diffraction studies confirmed the obtained structures.

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