Cooperative redox activation for carbon dioxide conversion

Abstract

A longstanding challenge in production chemistry is the development of catalytic methods for the transformation of carbon dioxide into useful chemicals. Silane and borane promoted reductions can be fined-tuned to provide a number of C1-building blocks under mild conditions, but these approaches are limited because of the production of stoichiometric waste compounds. Here we report on the conversion of CO2 with diaryldisilanes, which through cooperative redox activation generate carbon monoxide and a diaryldisiloxane that actively participate in a palladium-catalysed carbonylative Hiyama-Denmark coupling for the synthesis of an array of pharmaceutically relevant diarylketones. Thus the disilane reagent not only serves as the oxygen abstracting agent from CO2, but the silicon-containing ‘waste', produced through oxygen insertion into the Si–Si bond, participates as a reagent for the transmetalation step in the carbonylative coupling. Hence this concept of cooperative redox activation opens up for new avenues in the conversion of CO2.

Carbonylations with CO2 as the CO Source and Reactivity Modifier

“…[3,4] The reaction outcomes were good, and in particular they could be performed under mild reaction conditions.M ore interestingly,i nt hese two elegant studies,C O 2 not only acts as an interesting CO source,but it also adjusts the reactivity of the reactants and consequently improves the overall reaction results (Scheme 1). [3,4] The reaction outcomes were good, and in particular they could be performed under mild reaction conditions.M ore interestingly,i nt hese two elegant studies,C O 2 not only acts as an interesting CO source,but it also adjusts the reactivity of the reactants and consequently improves the overall reaction results (Scheme 1).…”

Efficient Water Reduction with sp3‐sp3 Diboron(4) Compounds: Application to Hydrogenations, H–D Exchange Reactions, and Carbonyl Reductions

“…[9,10] Whereas structurally different sp 3 -sp 3 diboron(4) compounds have been synthesized, their applications in organic synthesis have not been investigated in great detail. [12] Although unsuccessful in this respect, [13] we discovered that as eries of readily isolable and crystalline sp 3 -sp 3 diboron(4) reagents proved to be especially reactive for the reduction of water to dihydrogen. [12] Although unsuccessful in this respect, [13] we discovered that as eries of readily isolable and crystalline sp 3 -sp 3 diboron(4) reagents proved to be especially reactive for the reduction of water to dihydrogen.…”

Betaine Catalysis for Hierarchical Reduction of CO2 with Amines and Hydrosilane To Form Formamides, Aminals, and Methylamines

“…[17,19,20] Fori nstance,C antat et al described, for the first time,the four-electron reduction of CO 2 with amines and hydrosilane to access aminals in 2015. [21] Hitherto,the hierarchical reduction of CO 2 with amine and hydrosilane to access formamides,a minals, and methylamines remains unknown. [21] Hitherto,the hierarchical reduction of CO 2 with amine and hydrosilane to access formamides,a minals, and methylamines remains unknown.…”