反应详情

A solution of 6-ethyl-pyridin-2-ylamine (20 g, 0.164 mol) and triethylamine (29.6 mL, 0.213 mol) in dichloromethane (200 mL, 0.8 M) is cooled to 0° C. and carefully treated with pivaloyl chloride (26.2 mL, 0.213 mol). After stirring for 2 h, the solution is quenched with aq NaHCO3, extracted with dichloromethane and concentrated. The resulting oil is filtered through a plug of silica gel using ethyl acetate. The filtrate is concentrated and triterated with heptane to give N-(6-ethyl-pyridin-2-yl)-2,2-dimethyl-propionamide (18.3 g, 54%) as a white crystalline solid. mp 59-62° C.; Rf 0.31 (25% ethyl acetate in hexanes); 1H NMR (DMSO-d6, 300 MHz) δ 9.56 (s, 1 H), 7.85 (d, J=8.4 Hz, 1 H), 7.63 (t, J=7.8 Hz, 1 H), 6.93 (d, J=7.5 Hz, 1 H), 2.65 (q, J=7.8 Hz, 2 H), 1.20 (s, 9 H), 1.18 (t, 7.8 Hz, 3 H); LRMS calcd for C12H18N2O: 206.2; found 206.0 (M)+. Anal. Calcd for C12H18N2O: C, 69.87; H, 8.80; N, 13.58. Found C, 69.60; H, 8.67; N, 13.42.

1. customthe solution is quenched with aq NaHCO3
2. extractionextracted with dichloromethane
3. concentrationconcentrated
4. filtrationThe resulting oil is filtered through a plug of silica gel
5. concentrationThe filtrate is concentrated