Formaldehyde → Tetrahydro-N-methyl-N-(phosphonomethyl)-3-thiophenamine 1,1-dioxide

Participants

Reaction Steps

A mixture of N-methyltetrahydro-3-thiophenamine 1,1-dioxide hydrochloride (37.2 parts, 0.20 mole); 90 percent paraformaldehyde (6.8 parts, 0.22 mole); orthophosphorous acid (18.0 parts, 0.22 mole); and water (30 parts) was heated at its reflux temperature for 3 hours. After cooling, the solution was stirred into ethanol (150 ml.) and the sticky, white precipitate was triturated under more ethanol. After being dried in vacuo over P2O5 the product weighed 42.0 g. (86.3 percent yield). m.p. 222°-225° C.

Provenance & Evidence