| Summary: | A facile and efficient method has been developed for the synthesis of C3-difluoromethyl carbinol-containing imidazo[1,2-<i>a</i>]pyridines at room temperature via the HFIP-promoted Friedel–Crafts reaction of difluoroacetaldehyde ethyl hemiacetal and imidazo[1,2-<i>a</i>]pyridines. This strategy could be applied to the direct C(sp<sup>2</sup>)-H hydroxydifluoromethylation of imidazo[1,2-<i>a</i>]pyridines and afford a series of novel difluoromethylated carbinols in good to satisfactory yields with 29 examples. Furthermore, gram-scale and synthetic transformation experiments have also been achieved, demonstrating its potential applicable value in organic synthesis. This green protocol has several advantages, including being transition metal- and oxidant-free, being carried out at room temperature, having high efficiency, and having a wide substrate scope.
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