Preparation of 2,4,6-tri-isobutyl dihydro-1,3,5-dithiazine

Claim 1

A process for producing crystalline 2,4,6,-tri-isobutyl-dihydro-1,3,5-dithiazine having the structure: ##STR11## comprising the steps of: (i) reacting isovaleraldehyde with ammonium sulfide in the presence of citric acid in aqueous media a temperature of between 0° C. and 15° C. with the mole ratio of ammonium sulfide:isovaleraldehyde being between 2:1 and 1:0.5; the reaction time being between one and five hours thereby forming a gel; (ii) converting the resulting reaction mass gel to a two-liquid phase system; an organic phase and an aqueous phase by means of mechanical agitation of said gel; (iii) separating the aqueous phase from the organic phase; (iv) admixing the organic phase with aqueous mineral acid whereupon a crystalline precipitate is formed; (v) separating the resulting crystals from the resulting mixture; (vi) washing the resulting crystals with a non-dissolving hydrocarbon liquid; (vii) neutralizing the resulting washed crystals by dissolving said crystals in a solvent and admixing the resulting solution with a weak base; (viii) washing out the excess base from the resulting solution and drying the resulting organic solution; (ix) evaporating the solvent from said organic solution to yield 2,4,6-tri-isobutyl-dihydro-1,3,5-dithiazine in crystalline form.