Sodium Hydroxide → (E)-3-((3aS,5aR,5bR,7aR,9S,11aR,11bR,13aS)-9-hydroxy-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-3a-yl)acrylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of (E)-ethyl 3-((3aS,5aR,5bR,7aR,9S,11aR,11bR,13aS)-9-acetoxy-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-3a-yl)acrylate (1.6 g, 2.82 mmol) in tetrahydrofuran (THF) (15 mL), methanol (10 mL) and water (5 mL) was added sodium hydroxide (4.52 g, 113 mmol). The reaction mixture was stirred at 20° C. for 4 hs. The reaction mixture was evaporated to dryness and adjusted pH to 5 by saturated NH4Cl. The solid is solved into DCM (50 mL), washed with water, dried over Na2SO4 and concentrated to yield the (E)-3-((3aS,5aR,5bR,7aR,9S,11aR,11bR,13aS)-9-hydroxy-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-3a-yl)acrylic acid (1.2 g, 2.012 mmol, 71.3%) as a yellow solid.

Provenance & Evidence