p-Toluenesulfonic acid → HCID 70103652, compound

Participants

Reaction Steps

A mixture of 4-bromo-1-methoxy-3-(2-methoxyvinyl)benzene (42.3 g), 4-hydrazinopyridine (27.6 g), and p-toluenesulfonic acid (3.3 g) in ethanol (500 ml) was heated under reflux overnight, with stirring. The reaction mixture was filtered, and the filtrate was concentrated to about 50% of its initial volume. The precipitate was collected to give 5.5 g of product, as the hydrochloride salt, and the filtrate was concentrated. Saturated sodium hydrogen carbonate solution was added to the residue and the mixture was extracted with ethyl acetate. The organic extract was dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated. The residue was chromatographed on a Waters LC2000 instrument, gradient eluting with: 1% ethylamine/2% methanol/97% ethyl acetate/1% triethylamine acid/5% methanol/94% ethyl acetate. The appropriate fractions were collected and concentrated to yield 4.9 g (8.8%) of product, mp 142° C.

Provenance & Evidence