Reduction of CO₂ into Methylene Coupled with the Formation of C–S Bonds under NaBH₄/I₂ System

A selective four-electron reduction of CO2 with thiophenol using NaBH4 as a reductant is described to access dithioacetals. This reaction provides a novel synthetic method for the highly selective conversion of CO2 into methylene, and a new access to molecular structures via formation of C–S bonds using CO2 as the C1 source