Ammonium formate → Tert-butyl 10-(hydroxymethyl)-11-oxa-3,8-diazaspiro[5.5]undecane-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl 8-benzyl-10-(hydroxymethyl)-11-oxa-3,8-diazaspiro[5.5]undecane-3-carboxylate (2.00 g, 5.31 mmol) in methanol (38 mL) was added Pd(OH)2 (671 mg, 4.78 mmol) and ammonium formate (4.02 g, 63.7 mmol) and the mixture heated at 50° C. for 1 h. Additional catalyst (2.6 mmol) and ammonium formate (25 mmol) were added and the reaction heated for an additional 2 h. The reaction mixture was filtered and concentrated to ˜10 mL volume. The concentrate was diluted with dichloromethane and saturated sodium bicarbonate solution. The organic layer was separated and the aqueous layer washed with dichloromethane (5×50 mL). The combined organics were dried over Na2SO4, filtered, and concentrated to provide tert-butyl 10-(hydroxymethyl)-11-oxa-3,8-diazaspiro[5.5]undecane-3-carboxylate (1.37 g, 4.77 mmol, 90%) as an amber-colored glass. ESI-MS m/z calc. 286.2. Found 287.3 (M+1)+; Retention time: 0.65 minutes (3 min run).

Provenance & Evidence