反应详情

A solution of 3-oxo-tetrahydro-pyran-4-carboxylic acid ethyl ester (3.03 g, 17.6 mmol), R-(+)-α-methylbenzylamine (2.35 g, 19.4 mmol) and p-toluenesulfonic acid hydrate (67 mg, 230 μmol) in benzene (60 mL) was heated at reflux under a Dean-Stark trap for 16 h . The cooled mixture was concentrated in vacuo to provide the product as a yellow oily semisolid (5.05 g), used without further purification. 1H NMR (300 mHz, CDCl3) δ8.97 (bd, J=7.3 Hz, 1H), 7.3-7.2 (m, 5H), 4.41 (m, 1H), 4.30 (d, J=16.1 Hz, 1H), 4.18 (q, J=7.3 Hz, 2H), 3.91 (d, J=16.1 Hz, 1H), 3.64 (m, 2H), 2.34 (m, 2H), 1.48 (d, J=6.5 Hz, 3H), 1.30 (t, J=7.3 Hz, 3H).

1. temperatureat reflux under a Dean-Stark trap for 16 h
2. concentrationThe cooled mixture was concentrated in vacuo