反应详情

4,4-Dimethyl-2-(3-chloropropyl)-3H-1,2,4-benzothiazasiline 1,1-dioxide may be obtained in a manner similar to that described in Example 4 for the preparation of 3-(3-chloropropyl)-1,1-dimethyl-4-oxo-1,2,3,4-tetrahydro-3,1-benzazasiline, but using 3.2 g of 4,4-dimethyl-3H-1,2,4-benzothiazasiline 1,1-dioxide, 10.5 cm3 of n-butyllithium, 5.3 g of 1-chloro-3-bromopropane and 50 cm3 of tetrahydrofuran. After purification by flash chromatography on a silica column under a nitrogen stream at moderate pressure (0.5-1.5 bar) with a dichloromethane-cyclohexane mixture (50--50 by volume) as eluent, 1.95 g of 4,4-dimethyl-2-(3-chloropropyl) 3H-1,2,4-benzothiazasiline 1,1-dioxide are obtained.

1. customAfter purification by flash chromatography on a silica column under a nitrogen stream at moderate pressure (0.5-1.5 bar) with a dichloromethane-cyclohexane mixture (50--50 by volume) as eluent