C-H bonds as ubiquitous functionality: a general approach to complex arylated pyrazoles via sequential regioselective C-arylation and N-alkylation enabled by SEM-group transposition

The catalytic intermolecular C-H arylation of pyrazoles, namely SEM-protected pyrazoles with N-alkylpyrazoles, is described, which has helped in the synthesis of complex arylated pyrazoles. The catalytic C-H arylation combined with the protecting group transposition and N-alkylation has provided a rapid route for fully substituted pyrazoles with complete regiocontrol of all substituents.