N-tert-butoxycarbonyl-N-substituted hydrazines in SNAr displacements. Synthetic pathways to N-1-substituted anthrapyrazoles, aza-anthrapyrazoles and aza-benzothiopyranoindazoles

The synthesis of several N-tert-butoxycarbonyl(Boc)-protected-N-substituted hydrazines has been accomplished. The use of these protected hydrazines in SNAr substitutions leads to products in which the most nucleophilic nitrog en displaces the leaving group. Treatment of these compounds with trifluoro acetic acid readily removes the Boc-protecting group and the intermediates readily undergo cyclizations to yield N-1-substituted aza-benzothiopyranoin dazoles, anthrapyrazoles and aza-anthrapyrazoles. Side chain buildup was em ployed in the synthesis of several aza-anthrapyrazoles.