反应详情

84 mg (0.62 mmol) of 4-methylmorpholine N-oxide monohydrate and 207 mg of 4 Å molecular sieve are added to 92 mg (0.415 mmol) of [3-(chloromethylene)-2,3-dihydro-1-benzoxepin-7-yl]methanol, prepared according to example 71, in solution in 1 ml of dichloromethane. 14.6 mg (0.041 mmol) of tetrapropylammonium perruthenate are added to the suspension at 0° C. After stirring at ambient temperature for 1 hour, the reaction medium is purified by chromatography on silica gel (ethyl acetate/heptane 30/70) to give 70 mg (76%) of 3-(chloromethylene)-2,3-dihydro-1-benzoxepin-7-carbaldehyde in the form of a mixture of 2 Z/E isomers in an 85/15 ratio; 1H NMR (300 MHz, CDCl3) Z isomer: 4.90 (s, 2H), 6.41 (m, 3H), 7.14 (d, J=8.3 Hz, 1H), 7.70 (dd, J=8.3 and 2 Hz, 1H), 7.75 (d, J=2.07 Hz, 1H), 9.91 (s, 1H).

1. customprepared
2. customthe reaction medium is purified by chromatography on silica gel (ethyl acetate/heptane 30/70)