To a suspension of 3.12 g of sodium amide in 50 ml dry toluene was added
dropwise 12 g of 2-(dimethylamino)ethylaminopyridine. The mixture was
refluxed for 2 hours, cooled to 50°C, and 21 g 3-thenyl bromide was added
dropwise. When reaction subsided, the brownish-orange mixture was refluxed
for 0.5 hour, cooled, and poured into 150 ml of water. The toluene layer was
separated, extracted with 5% hydrochloric acid. This extract was saturated
with potassium carbonate. The free base was extracted with ether, dried and
fractionated. Yield of N,N-dimethyl-N'-2-pyridinyl-N'-(3-thienylmethyl)-1,2-
ethanediamine 31%, boiling point 169-172°C/1 mm.
106 g of the free base was dissolved in 500 ml of isopropyl alcohol and 34 ml
concentrated hydrochloric acid was added. After shaking, the reaction mixture
was allowed to added. After through cooling in an ice-methanol mixture, the
salt was collected and washed on the filter with low boiling petroleum ether,
Melting point of N,N-dimethyl-N'-2-pyridinyl-N'-(3-thienylmethyl)-1,2-
ethanediamine hydrochloride 169.5-170°C.
