1,2-Dichloroethane → Tert-butyl[2-(3-butoxy-3-o-tolyl-azetidin-1-yl)-1-(2-hydroxy-4-methoxybenzyl)-2-oxo-ethyl]carbamate

Participants

Reaction Steps

74 mg (0.4 mmol) of EDC and 52 mg (0.4 mmol) of HOBt are added to a solution of 100 mg (0.3 mmol) of 2-tert-butoxycarbonylamino-3-(2-hydroxy-4-methoxyphenyl)-propanoic acid in 5 ml of dimethylformamide. The mixture is stirred for 15 min and 107 mg (0.3 mmol) of 3-butoxy-3-o-tolylazetidine trifluoroacetate are added. After stirring for a further 15 minutes at ambient temperature, 0.3 ml (1.3 mmol) of diisopropylethylamine is added. The reaction medium is stirred for 2 h, and then 10 ml of a 1N aqueous solution of hydrochloric acid are added and the medium is extracted with ethyl acetate. The organic phase is washed with water and then dried over magnesium sulphate, filtered and evaporated. The residue is filtered through silica gel (eluent: 70/30 heptane/ethyl acetate). 220 mg of tert-butyl[2-(3-butoxy-3-o-tolylazetidin-1-yl)-1-(2-hydroxy-4-methoxybenzyl)-2-oxoethyl]carbamate are obtained in the form of a yellow oil and are used crude in the next stage.

Provenance & Evidence