Diisobutylaluminum hydride → (3R)-N-(benzyloxy)-6-cyclohexyl-3-(4-formyl-1,3-oxazol-2-yl)hexanamide

Participants

Reaction Steps

A solution of ethyl 2-((1R)-1-{2-[(benzyloxy)amino]-2-oxoethyl}-4-cyclohexylbutyl)-1,3-oxazole-4-carboxylate (preparation 155) (1.50 g, 3.39 mmol) in toluene (50 ml) at −78° C. was treated dropwise with DIBAL (1M in hexanes) (11.86 ml, 11.86 mmol) and stirred at this temperature for 30 minutes. MeOH (12 ml) was added to quench the reaction and the reaction mixture allowed to warm to room temperature. Alternate portions of NaHCO3 and MgSO4 were added to the reaction mixture to form a white paste. EtOAc was added and the solid filtered off. The solvent was removed under reduced pressure. The crude material was purified on a silica column eluting with a solvent gradient of EtOAc:pentane (1:1) gradually changing to (1:0) to afford the title compound as a colourless oil (605 mg, 45%).

Provenance & Evidence