Formaldehyde → (R)-1-(4-(10,11-dihydro-5H-dibenzo[b,f]azepin-5-yl)-2-butyn-1-yl)-3-piperidinecarboxylic acid ethyl ester

Participants

Reaction Steps

A solution containing 5-propargyl-10,11-dihydro-5H-dibenzo[b,f]azepine (2.45 g, 10.5 mmol, prepared similarly as described in U.S. Pat. No. 3,354,178 (1967)), (R)-3-piperidinecarboxylic acid ethyl ester (1.7 g, 10.8 mmol), paraformaldehyde (0.65 g) and a trace of cuprous chloride in dioxane (25 ml) was heated at reflux temperature for 5 h and left standing overnight. The mixture was filtered and the solvent evaporated. The remaining oil was purified by column chromatography on silica gel (40 g) using chloroform as eluent, affording 3.5 g (83%) of (R)-1-(4-(10,11-dihydro-5H-dibenzo[b,f]azepin-5-yl)-2-butyn-1-yl)-3-piperidinecarboxylic acid ethyl ester.

Provenance & Evidence