Potassium Carbonate → (R)-1-(2-(6,11-dihydrodibenzo[b,e]thiepin-11-ylidene)-1-ethyl)-3-piperidinecarboxylic acid ethyl ester hydrogen oxalate

Participants

Reaction Conditions

Reaction Steps

To a solution of 11-(2-bromoethylidene)-6,11-dihydrodibenzo[b,e]thiepine (4.43 g, 0.014 mol, Coll.Czech.Chem.Comm. 52, 1566 (1987)) in N,N-dimethylformamide (75 ml), potassium carbonate (19.3 g, 0.14 mol) and (R)-3-piperidinecarboxylic acid ethyl ester tartrate (6.43 g, 0.0209 mol) were added and the mixture was stirred at 70° C. for 6 h. The reaction mixture was diluted with benzene (300 ml), the solid was filtered off and the filtrate was washed with water (5×80 ml). The benzene solution was dried (MgSO4) and the solvent removed in vacuo. The oily residue (6.83 g) was dissolved in acetone and treated with a solution of oxalic acid in ethanol. The solid was isolated and the crude hydrogen oxalate (5.8 g) was recrystallised from a mixture of 96% ethanol and ether to yield 5.81 g (86%) of (R)-1-(2-(6,11-dihydrodibenzo[b,e]thiepin-11-ylidene)-1-ethyl)-3-piperidinecarboxylic acid ethyl ester hydrogen oxalate.

Provenance & Evidence