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A facile esterification of α,β-unsaturated aldehydes with alcohols has been developed for the synthesis of esters by using bulky N-heterocyclic (NHC) carbene as a metal-free and eco-friendly organocatalyst. This new protocol has been proved to be effective with a wide substrate scope, giving selective esters in yields greater than 84% under mild conditions. Moreover, proposed synthetic strategy enables modification of various types of silsesquioxanes (SQ) which cannot or are technically difficult to be carried out with known protocols. For the first time, a one-pot sequential esterification/hydrosilylation has been successfully carried out. [ABSTRACT FROM AUTHOR]

Synthesis and characterization of a new bifunctional N‐heterocyclic carbene precursor with sterically expanded substituents is described. The obtained NHC is employed in the catalytic system for hydrosilylation of internal alkynes providing a fully selective and effective process in mild conditions under air. Comparison of the performance of the newly developed catalytic system with its analogs based on monofunctional NHC ligands proves that the presence of two metal atoms and the proper design of the steric environment around the metal center ensure a definitely greater activity in the hydrosilylation process. [ABSTRACT FROM AUTHOR]