tert-Butyl isocyanate → N-(3-(2-acetamido-1-(tert-butylamino)-1-oxohex-5-en-2-yl)-1-(4-chlorophenyl)cyclobutyl)benzamide

Participants

Reaction Steps

A suspension of N-(1-(4-chlorophenyl)-3-pent-4-enoylcyclobutyl)benzamide (1.21 g, 3.0 mmol), ammonium acetate (2.08 g, 27.0 mmol) in 2,2,2-trifluoroethanol (12 mL) was treated with tert-butylisocyanate (2 mL, 18.0 mmol). After stirring for three days at room temperature, the reaction was quenched with 1M HCl (5 mL) and diluted with ethyl acetate (15 mL). After vigorous stirring for 1 h, the phases were separated and the organic layer was washed successively with 1 M HCl, water and saturated aqueous sodium chloride. The solution was dried over MgSO4, filtered and concentrated to give the crude product as a mixture of diastereomers (1.77 g). It was used to the next step without further purification. ESI MS found for C29H36ClN3O3 m/z [510.7/512.7 (M+1), 508.7/509.9 (M−1)].

Provenance & Evidence