Cascade 1,3-dipolar Cycloaddition/SO2 extrusion approach for the rapid synthesis of tetraaryl-substituted pyrazoles with Aggregation Induced Emission characteristics

A highly efficient strategy was developed for the straightforward synthesis of tetraaryl-substituted pyrazoles. The cascade process consists of a regioselective 1,3-dipolar cycloaddition of benzosultam-3-ylidenes with nitrile imines and a subsequent elimination of SO2. The title compounds exhibit high fluorescence quantum yields and Aggregation Induced Emission (AIE) characteristics. [Display omitted] •A new strategy was reported for the synthesis of tetraaryl-substituted pyrazoles.•Milder reaction conditions and shorter synthetic route were achieved.•Several compounds exhibit high fluorescence quantum yields and AIE characteristics.