1,4,2-DIAZAPHOSPHOLOTHIAZOLES AND 1,4,2-DIAZAPHOSPHOLOPYRIDINES BY A HANTZSCH-TYPE CONDENSATION USING CHLOROMETHYLDICHLOROPHOSPHANE

The [3 + 2] cyclocondensation of 2-amino-1,3-thiazoline, 2-aminopyridi nes, 2- and 4-aminopyrimidines, 2-aminopyrazine, and 2-aminoquinoline with chloromethyldichlorophosphane in the presence of triethylamine yi elds regiospecifically 5,6-dihydrothiazolo[2,3-e][1,4,2]diazaphosphole (3), 1,4,2-diazaphospholo[4,5-a]pyridines (12), 1,4,2-diazaphospholo[ 4,5-a]pyrimidines (15), 1,4,2-diazaphospholo[4,5-e]pyrimidine (17), 1, 4,2-diazaphospholo[4,5-a]pyrazine (19), and [1,4,2]diazaphospholo[4,5- a]quinoline (22), respectively. Using 2-amino-1,3-thiazole (4) and 2-a minobenzothiazoles 8, we obtained mixtures of the 1,5- and 4,5-anellat ed 1,4,2-diazaphospholes 5/6, 9a/10a and 9b/10b, while in the case of the methyl derivative 8c only the [1,4,2]diazaphospholo[5,4-b][1,3]ben zothiazole 10c was formed. In the reaction of 2-aminothiazole and 2-am inopyrazine with chloromethyldichlorophosphane the bis(diazaphospholo) -substituted chloromethylphosphanes 7 and 20 could be detected. The ne w anellated 1,4,2-diazaphospholes are colorless to pale yellow crystal line moisture-sensitive solids.