activates the S-N bond toward cleavage, and in the second, a sulfoximine nucleophilically attacks the sulfonyl group, resulting in the elimination of the pyrazole moiety. This process yields sulfonyl amidines, compounds with significant medicinal relevance, while the liberated pyrazole effectively participates in subsequent reactions with Michael acceptors. Notably, the protocol operates without the need for transition-metal catalysts and exhibits broad substrate scope along with excellent functional group tolerance.
Kour et al. (Tue,) studied this question.