Sodium ethoxide → 5-(4,4-Dimethyl-2-thioxo-1,4-dihydro-2H-3,1-benzoxazin-6-yl)-1H-pyrrole-2-carbonitrile

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl 2-cyano-5-(4,4-dimethyl-2-thioxo-1,4-dihydro-2H-3,1-benzoxazin-6-yl)-1H-pyrrole-1-carboxylate (0.5 g, 1.3 mmol, 1 eq) in THF (5 mL) was added NaOEt (0.27 g, 3.9 mmol, 3 eq) in EtOH (5 mL) and the reaction was heated to 80° C. for 2 h. The solvents were removed in vacuo and the residue partitioned between ethyl acetate (100 mL) and water (100 mL). The layers were separated and the aqueous layer was extracted with ethyl acetate (100 mL). The organic layers were combined, washed with brine (50 mL), dried over magnesium sulfate, filtered and concentrated in vacuo. Purification by flash column chromatography (10% ethyl acetate/hexane) gave the title compound (0.27 g, 73%) as a brown powder, mp 261-262° C. 1H NMR (DMSO-d6) δ1.68 (s, 6H), 6.72-6.73 (m, 1H), 6.99-7.01 (m, 1H), 7.06 (d, 1H, J=7.9 Hz), 7.66-7.70 (m, 2H) 12.26 (s, 1H), 12.62 (s, 1H); MS (ESI) [M−H]−=282; Anal. Calcd. For C15H13N3OS: C, 63.58; H, 4.62; N, 14.83. Found: C, 63.25; H, 4.78; N, 15.11.

Provenance & Evidence