Organophotocatalytic silyl transfer of silylboranes enabled by methanol association: a versatile strategy for C-Si bond construction

Development of a mild, robust and metal-free catalytic approach for silyl transfer of silylboranes is critical for the advancement of modern organosilicon chemistry given their powerful capacity in the construction of C-Si bonds. Herein, we wish to disclose a visible light-induced organophotocatalytic strategy, where methanol association with boron atoms enables the photocatalytic generation of silyl radicals. Notably, the protocol is capable of accommodating a wide range of radial acceptors through slightly tuning the reaction conditions, which allows the formation of various types of C-Si bonds. The preparative power of the transformations has been further highlighted in a number of complex settings, including late-stage functionalization and radical cascade reactions. Furthermore, this technology could be extended to the construction of C-B, C-S and C-Sn bonds, thus offering a versatile platform for bond activation and connection of main group elements. The green aspect of the reaction has also been demonstrated by using Brij-30/water as a reaction solvent or sunlight as an alternative energy source.