Pyridine → 4-Chlorobutyl (1S,2E)-3-{(1R,2R,3S,5R)-2-[(2Z)-7-(Ethylamino)-7-oxohept-2-en-1-yl]-3,5-dihydroxycyclopentyl}-1-(2-phenylethyl)prop-2-en-1-yl Carbonate

Participants

Reaction Conditions

Reaction Steps

To a solution of bimatoprost boronate b-1 (529 mg, 1.10 mmol) in THF was added DMAP (6.9 mg, 0.055 mmol). The solution was cooled to 0° C. and successively slowly added pyridine (0.22 mL, 2.75 mmol) and 4-chlorobutyl chloroformate (0.375 mL, 2.75 mmol). Allowed to stir at ambient temperature over 2 days. Added more pyridine (89 uL, 1.11 mmol) and 4-chlorobutyl chloroformate (150 uL, 1.10 mmol) and stirred for another 24 h. The resultant mixture was concentrated under reduced pressure, residue partitioned with ethyl acetate and water. Washed organic layer with brine, dried over sodium sulfate, filtered, and concentrated in vacuo to provide 808 mg (134%) of a crude oil, which was used without further purification.

Provenance & Evidence