Computational Study of B(C6F5)3-Catalyzed Selective Deoxygenation of 1,2-Diols: Cyclic and Noncyclic Pathways

The selective deoxygenation of polyols has emerged as an attractive approach to transform biomass-derived polyols into valuable building blocks. Herein, we present a theoretical study on the boron-catalyzed selective deoxygenation of terminal 1,2-diols. The computational results explain the different product distributions obtained with different silanes and unveil the critical role of the cyclic siloxane intermediate. Compared to noncyclic pathways, the cyclic pathway facilitates the initial deoxygenation process because the cyclic structure minimizes the steric repulsions between the reagents. It avoids overreduction because the generated bulky disiloxane moiety hinders the second deoxygenation.