Facile synthesis of α-monofluoromethyl alcohols: Nucleophilic monofluoromethylation of aldehydes using TMSCF(SO2Ph)2

α-Fluoromethyl phenyl sulfone derivatives have been extensively employed in various reactions as versatile fluoromethylating reagents. While nucleophilic monofluoromethylations of aldehydes have been achieved using fluoromethyl phenyl sulfone or fluorobis(sulfonyl)methanes, a facile protocol under mild reaction conditions remains an ardently sought goal. We now report a feasible synthetic approach toward β-monofluorinated alcohols using α-trimethylsilyl-α-fluorobis(phenylsulfonyl)methane [TMSCF(SO2Ph)2, TFBSM] as a novel monofluoromethylating reagent. Initiated by a catalytic amount of fluoride, the reagent can be readily added to a variety of aldehydes providing the desired products in high yields. Computational and kinetic studies have revealed the exceptional lability of the Si–C bond in TFBSM compared with other fluoromethylsilane counterparts.

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► α-Trimethylsilyl-α-fluorobis(phenylsulfonyl)methane (TFBSM) is prepared.
► The reagent can be added to various aldehydes.
► Mechanistic studies have rationalized the exceptional lability of the Si–CF bond in TFBSM.
► Natures of Si–CF bonds in a series of fluoromethyl silyl reagents have been investigated.