Pyridine → (R)-tert-butyl 1-cyanoethylcarbamate

Participants

Reaction Steps

To a solution of (R)-tert-butyl 1-amino-1-oxopropan-2-ylcarbamate (Int-X-A, 1 g, 5.31 mmol) and 4-methylbenzene-1-sulfonyl chloride (4.05 g, 21.25 mmol) in CH2Cl2 (5 mL) was added pyridine (2.101 g, 26.6 mmol). After 3 h, acetic anhydride (0.651 g, 6.38 mmol) was added. This was stirred overnight before it was concentrated and EtOAc was added. Saturated NaHCO3 was added and the two phase mixture was stirred vigorously for 2 h. The organic layer was washed with 1 N HCl and then saturated NaHCO3. The organic layer was dried and concentrated. The resulting residue was purified by flash chromatography (Isco Combiflash Companion, 40 g silica gel, 15% ethyl acetate-hexane) to provide the product (R)-tert-butyl 1-cyanoethylcarbamate (Int-X-B, 336 mg, 1.974 mmol, 37.2% yield); [M+Na]+=193.2; 1H NMR (400 MHz, methanol-d4) δ ppm 4.51 (1 H, q), 1.34-1.58 (12 H, m).

Provenance & Evidence