Highly efficient regioselective hydrosilylation of allenes using a [(3IP)Pd(allyl)]OTf catalyst; first example of allene hydrosilylation with phenyl- and diphenylsilane

Abstract

A [(3IP)Pd(allyl)]OTf complex was shown to function efficiently and regioselectively in allene hydrosilylation with phenyl- and diphenylsilane. The catalyst also proved to be highly active for allene hydrosilylation employing a wide range of silanes, each of which produced a single regioisomer.

Regiodivergent and Stereoselective Hydrosilylation of 1,3‐Disubstituted Allenes

“…[5] However,e ven the best methods often lack high levels of regio-and stereoselectivity for substrates without inherent steric or electronic biases.A llenes represent ar eagent class that potentially offers access to both alkenyl and allylsilanes by regiodivergent hydrosilylation reactions, but the presence of two orthogonal and often comparably reactive p-systems presents aconsiderable challenge in terms of regiocontrol. [6,7] Fort hese reasons,a llene hydrosilylations have received little attention, [8] with the Lewis acid catalyzed hydrosilylation of 1,3-disubstituted allenes towards trisubstituted E-configured trialkyl alkenylsilanes (Figure 1) being ar are example that exhibits regiocontrol and stereoselectivity. [8a] As part of ag eneral program to develop and understand regiodivergent catalytic processes, [9] previous studies from our laboratory described the regiodivergent hydrosilylation of terminal allenes in processes that exploit the electronic and steric bias of monosubstituted allenes and that utilize metal identity and ligand structure as key control elements.…”

Supported Au Nanoparticles‐Catalyzed Regioselective Dehydrogenative Disilylation of Allenes by Dihydrosilane

“…To the best of our knowledge, all known reported examples regarding the reaction between a dihydrosilane and an allene afford the typical hydrosilylation products, such as using as catalysts Pd II , Mo(CO) 6 or Co II . The direct 1,2‐disilylation of allenes by disilanes is a long known transformation, yet not extensively studied .…”

A Bithiophene‐Promoted ppm Levels of Palladium‐Catalyzed Regioselective Hydrosilylation of Terminal Allenes

“…Hence, the development of new and efficient methods for the synthesis of versatile allylsilanes has been paid more and more attention. The hydrosilylation of allenes is one of the most straightforward and atom‐economical approaches to prepare such compound, which has been achieved with various metal catalysts, such as Mo, Co, Ni, Pd and Au . However, controling the regio‐ and stereoselectivity is still challenging in this reaction, as up to six potential isomeric products can be generated (Figure a).…”

“…Another method for branched allylsilanes was developed by Schmidt et al. by using their 3‐iminophosphine ligands coordinated with Pd(II) (Figure , L3 ) . It is also worth mentioning that more recently our group applied a conjugated microporous polymer as an efficient heterogeneous catalytic ligand for the Pd‐catalyzed regioselective allene hydrosilylation .…”