反应详情

Alternatively, a mixture of 6-cyano-3,4-dihydro-2,2-dimethyl-trans-3-hydroxy-4-(4-methoxy-2-oxo-3-pyrrolin-1-yl)-2H-1-benzopyran (0.7 g), benzyl alcohol (0.92 ml) and methanesulfonic acid (0.01 g) was refluxed for 2 hours in the presence of 3A molecular sieves. After cooling the molecular sieves were filtered off, the filtrate stirred with diethylether, the insoluble product filtered off and washed twice with diethylether, to give 6-cyano-3,4-dihydro-2,2-dimethyl-trans-3-hydroxy-4-(4-benzyloxy-2-oxo-3-pyrrolin-1-yl)-2H-1-benzopyran, m.p. 248° C.

1. temperatureAfter cooling the molecular sieves
2. filtrationwere filtered off
3. filtrationthe insoluble product filtered off
4. washwashed twice with diethylether