9-Fluoro-11beta,16alpha,17,21-tetrahydroxypregn-4-ene-3,20-dione → 9-Fluoro-11beta,17,21-trihydroxy-16alpha-[(2-phenyl-2-propenyl)oxy]pregn-4-ene-3,20-dione

Participants

Reaction Conditions

Reaction Steps

The solution of 2-phenyl-3-diazo-1-propene prepared as described above is diluted with 150 ml of cold methanol and stirred well at 0°C as 13 g of 9-fluoro-11β,16α,17,21-tetrahydroxypregn-4-ene-3,20-dione, 16,17-cycloborate is added in portions. The slurry is stirred for 1 hour at 0°C and filtered to give 9.6 g of the title compound. The filtrate is stirred at room temperature for 1 hour with 4 g of the cycloborate and the resulting solution is cooled to 0°C and filtered to give 4.2 g of the title compound. The filtrate is evaporated in vacuo and the residue is dissolved in 400 ml of 3:1 ether-methanol and cooled to -10°C to give a further 3.0 g of material. A small sample recrystallized from acetone-hexane has a melting point of 161°-163.5°C.

Provenance & Evidence