Sodium Bicarbonate → (9-(2-Chloro-3-(2-hydroxyethyl)benzyl)-1-oxa-4,9-diazaspiro[5.5]undecan-4-yl)(2-ethylthiazol-4-yl)methanone

Participants

Reaction Steps

To a solution of 2-chloro-3-(2-hydroxyethyl)benzaldehyde (1.1 molar equivalents) in DCM (12 volumes) was added to (2-ethylthiazol-4-yl)(1-oxa-4,9-diazaspiro[5.5]undecan-4-yl)methanone ((limiting reagent) (step b). Triethylamine (2 molar equivalents) was added and the mixture was stirred for 1.15 hr. Sodium triacetoxyborohydride (2.5 molar equivalents) was added portion-wise over 15 minutes maintaining the temperature below 25° C. The reaction mixture was stirred at ambient temperature for 22.5 hr. Saturated aq. sodium bicarbonate solution (8 volumes) was added slowly and the mixture was stirred vigorously for 1 hr; the aqueous was separated and extracted with DCM (5.3 volumes). The combined organics were washed with 20% brine solution (5.3 volumes), dried over anhydrous sodium sulfate, filtered and evaporated to give a brown oil. Yield 107% of theoretical.

Provenance & Evidence