Visible-light-mediated deuteration of silanes with deuterium oxide

Isotopically labeled compounds are highly desirable as they can serve as both mechanistic probes in chemistry and diagnostic tools in medicinal research. Herein, we report an unprecedented visible-light-mediated metal-free deuteration of silanes using D2O as an inexpensive, readily available, and easy to handle deuterium source. A broad range of aryl- and alkyl-substituted silanes were deuterated with high deuterium incorporations and yields. Furthermore, a 100 gram-scale synthesis was demonstrated using continuous-flow micro-tubing reactors, where enhanced reaction efficiency was obtained. The photoredox-catalyzed polarity matched hydrogen atom transfer (HAT) between silanes and the thiol HAT catalyst was responsible for the efficient deuteration.