Novel dealkylating and deaminating reactions of 2-chlorobenzoxazole, 2-chloropyridine and methyl 2-chloro-5-nitrobenzoate with N-amino compounds

Abstract

2-Chlorobenzothiazole (I) and N,N-dimethylhydrazine undergo anomalous reaction to yield N-methyl-N-(2-benzthiazolyl)-hydrazine (V) (79%), 2-dimethylaminobenzothiazole (X) (20%) and traces of 2-methylaminobenzothiazole (XI) (1%). With N-aminopiperidine and N-aminomor-pholine I forms 2-piperidino-(XIII)- and 2-morpholino-(XIV)-benzothiazoIes respectively arising by the deamination of N-aminomorpholine and N-aminopiperidine. 2-Chlorobenzoxazole (II) and N,N-dimethylhydrazine produce preponderantly deaminated derivative XV, some dealky-lated product VI and also dimethyl hydrazinobenzoxazole XVI. II also dealkylates N,N-dimethyl-cyclohexylamine to yield XV and XVII. 2-Chloropyridine and N,N-dimethyIhydrazine react under forcing conditions to form 2-dimethylamino-(XVIII)- and 2-methylamino-(XIX)-pyridines. Methyl 2-chloro-5-nitrobenzoate (XXII) demethylates N,N-dimethylhydrazine to form the ind-azolone XXIII, while benzyl bromide merely quaternizes it. These observations are rationalized and plausible mechanisms suggested.