A comprehensive review on the silane-acid reduction of alkenes in organic synthesis.

Target and diversity-oriented synthesis represents a versatile and efficient strategy for constructing structurally complex and privileged scaffolds from readily or commercially accessible starting materials. The combination of reagents indeed plays a pivotal role in organic synthesis, acting as chemical "tools" that enable specific reactions to occur and driving the creation of new molecules. Reagents facilitate organic transformations, including the controlling of reaction pathways and influencing the complex efficiency and selectivity of the synthesis process. This review highlights the combined use of triethylsilane and trifluoroacetic acid as a powerful system for the chemoselective and regioselective ionic hydrogenation of diverse alkenes. The transformation proceeds through protonation, followed by hydride transfer, affording valuable products with high selectivity. Furthermore, this review covers the reduction of heterocyclic skeletons to saturated compounds via the ionic hydrogenation method.