Diisopropylethylamine → 1-[(7-Methoxy-1,2,3,4-tetrahydro-naphth-2-yl)methyl]-1,2,5,6-tetrahydropyridine-3-carboxylic acid methyl ester

Participants

Reaction Steps

To a solution of 5.19 g (15 mmol) of p-toluene-sulphonic acid (7-methoxy-1,2,3,4-tetrahydro-naphth-2-ylmethyl) ester in 75 ml of dimethylformamide there are added first 3.66 g (16.5 mmol) of 1,2,5,6-tetrahydropyridine-3-carboxylic acid methyl ester hydrobromide (guvacoline hydrobromide) and then 6.78 g (52.5 mmol) of N-ethyl-N,N-diisopropylamine. The mixture is stirred at 60° for 18 hours and then concentrated by evaporation under a high vacuum. Water is added to the residue and extraction is carried out with diethyl ether. The organic phases are washed with water and extracted with 2N hydrochloric acid. The hydrochloric acid extracts are rendered alkaline at reduced temperature with sodium hydroxide solution (30%) and are extracted with dichloromethane, whereupon the combined organic phases are dried over sodium sulphate and concentrated by evaporation under reduced pressure. 1-[(7-methoxy-1,2,3,4-tetrahydro-naphth-2-yl)methyl]-1,2,5,6-tetrahydropyridine-3-carboxylic acid methyl ester is obtained in the form of a light-yellow oil.

Provenance & Evidence