The vicarious nucleophilic substitution of hydrogen and related reactions in nitrobenzoxazoles

Article abstract of DOI:10.1016/0040-4020(95)00351-8

5- and 6-nitrobenzoxazoles 3 and 4 react with nucleophiles exclusively at C-2, giving ring opening products. If position 2- is blocked with phenyl substituent the reaction takes place in the carbocyclic ring affording the VNS products. 2-Methylthio-5-nitrobenzoxazole 7 and its 6-nitro isomer 8 give products which result from addition of a nucleophile to the carbocyclic ring (VNS) as well as to the heterocyclic ring (S(N)Ar and ring cleavage). 2-Methylthiobenzoxazoles can be readily converted to the corresponding benzoxazolones via oxidative hydrolysis.