HCID 53923952, compound → HCID 9888409, compound

Participants

Reaction Steps

—1,1′-(Azodicarbonyl)dipiperidine (5.54 g) was added to an ice-cooled solution of compound 13a (2.0 g), triphenylphosphine (5.76 g), and phenol (2.06 g) in dry THF (10 ml). After 5 min. stirring dry THF (60 ml) was added and the reaction mixture was stirred for 2 h at room temperature. Then it was poured into heptane (100 ml); the resulting mixture was filtered and the filtrate was concentrated under reduced pressure. Column chromatography afforded (3β,5α,20R)4,4-dimethyl-20-phenoxypregna-8,14-dien-3-ol benzoate (compound 14b), together with the elimination products (3β,5α)-4,4-dimethylpregna-8,14,17(20)-trien-3-ol benzoate and (3β,5α)-4,4-dimethylpregna-8,14,20-trien-3-ol benzoate (2.80 g totally). The product was used in the following step without further purification.

Provenance & Evidence