1,3-Propanediamine, N'-(ethylcarbonimidoyl)-N,N-dimethyl-, monohydrochloride → 6,6-diphenyl-1 (2-trimethylsilanylethoxymethyl)-6,7-dihydro-1H-indazole-3-carboxylic acid (2-chloroethyl)amide

Participants

Reaction Conditions

Reaction Steps

0.677 g of 1-hydroxybenzotriazole hydrate, 0.958 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, 1.16 g of 2-chloroethylamine hydrochloride and 1.4 cm3 of triethylamine are successively added to a solution of 1.8 g of 6,6-diphenyl-1-(2-trimethylsilanylethoxymethyl)-6,7-dihydro-1H-indazole-3-carboxylic acid in 300 cm3 of dichloromethane. After stirring the reaction mixture for about 4 hours at a temperature in the region of 20° C., it is washed with three times 60 cm3 of water, dried over magnesium sulphate, filtered and concentrated to dryness under reduced pressure (13 kPa). After flash chromatography on a column of silica [eluent: cyclohexane/ethyl acetate (85/15 by volume)], 1.2 g of 6,6-diphenyl-1-(2-trimethylsilanylethoxymethyl)-6,7-dihydro-1H-indazole-3-carboxylic acid (2-chloroethyl)amide are thus obtained in the form of a resin, the characteristics of which are as follows:

Provenance & Evidence