Sodium borohydride → tert-Butyl 1-vinyl-2-hydroxy-8-azaspiro[4.5]decane-8-carboxylate
Reaction equation
[CH:1]([CH:3]1[C:7]2([CH2:12][CH2:11][N:10]([C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[CH2:9][CH2:8]2)[CH2:6][CH2:5][C:4]1=[O:20])=[CH2:2].[BH4-].[Na+]>CO>[CH:1]([CH:3]1[C:7]2([CH2:8][CH2:9][N:10]([C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[CH2:11][CH2:12]2)[CH2:6][CH2:5][CH:4]1[OH:20])=[CH2:2]Participants
4
Procedure
A solution of tert-butyl 1-vinyl-2-oxo-8-azaspiro[4.5]decane-8-carboxylate (0.59 g, 2.11 mmol) from Procedure 17, Step B in methanol (6 mL) was cooled to −70° C. and sodium borohydride (0.022 g, 0.60 mmol) was added. The reaction was allowed to warm to room temperature for 3 h and was then quenched with the addition of 1N hydrochloric acid. The mixture was diluted with water and extracted twice with ether. The combined ether layers were washed with brine, dried over sodium sulfate, filtered, and concentrated. The residue was purified by flash chromatography eluting with 20% ethyl acetate in hexanes to afford the title compound (0.621 g). 1H NMR (400 MHz, CDCl3) indicated a mixture of isomers which was used in the next step.