Water → 2-(3-Chloropropyl)-4,4-dimethyl-1,2,3,4-tetrahydro 1isoquinolinone

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Reaction Conditions

Reaction Steps

2-(3-Chloropropyl)-4,4-dimethyl-1,2,3,4-tetrahydro-1-isoquinolinone may be obtained in the following manner: 25.7 cm3 of n-butyllithium (1.6 M in hexane) are added to a solution of 6 g of 4,4-dimethyl-1,2,3,4-tetrahydro-1-isoquinolinone in 120 cm3 of tetrahydrofuran, at -76° C. under a nitrogen stream. The reaction mixture is left for three hours at 0° C. 13 g of 1-chloro-3-bromopropane are then added and the mixture is stirred for 18 hours at a temperature of about 25° C. The reaction mixture is treated with 240 cm3 of water and extracted with three times 100 cm3 ethyl acetate. The combined organic phases are dried over magnesium sulphate and evaporated to dryness at 40° C. under reduced pressure (20 mm of mercury; 2.7 KPa). The residue is purified by flash chromatography on a silica column under a nitrogen stream at moderate pressure (0.5-1.5 bar) with a dichloromethane-methanol mixture (99.5-0.5 by volume) as eluent. 3.9 g of 2-(3-chloropropyl)-4,4-dimethyl-1,2,3,4-tetrahydro 1isoquinolinone are obtained; melting point =131° C.

Provenance & Evidence