tert-Butyl carbazate → tert-butyl N-[(E)-hept-6-enylideneamino]carbamate

Participants

Reaction Steps

To a solution of 5 (68 mg, 0.610 mmol) and tert-butyl carbazate (81 mg, 0.613 mmol) in MeOH (5 mL) was added ground molecular sieves (115 mg, 3 Å). The mixture was stirred for 3 h after which it was filtered through celite and evaporated. The residue was dissolved in dry THF (3 mL) and AcOH (3 mL). NaBH3CN (95 mg, 1.51 mmol) was added and the solution was stirred over night. The reaction mixture was diluted with saturated NaHCO3 solution (6 mL) and EtOAc (6 mL). The organic phase was washed with brine, saturated NaHCO3, brine, dried over MgSO4 and evaporated. The cyanoborane adduct was hydrolyzed by treatment with MeOH (3 mL) and 2 M NaOH (1.9 mL). The mixture was stirred for 2 h and the MeOH was evaporated. H2O (5 mL) and DCM (5 mL) were added and the water phase was extracted three times with DCM. The combined organic phases were dried and evaporated. Purification by flash column chromatography (toluene/ethyl acetate 9:1 with 1% triethylamine and toluene/ethyl acetate 6:1 with 1% triethylamine) provided the title compound (85 mg, 61%) as an oil.

Provenance & Evidence