Novel Palladium-Catalyzed Atom-Efficient Cross-Coupling Reaction by Means of Hexaarylcyclotrisiloxane

Abstract

Hexaarylcyclotrisiloxane, which is one of the most stable derivatives of diarylsilanediol, was found to undergo palladium-catalyzed cross-coupling reaction with aryl halides in good yields. The reaction is performed in an aqueous medium taking potassium hydroxide as an activator. Both of the two aryl groups attached to each silicon atom could be utilized. Some base-sensitive functionality such as acetyl and nitro groups survived the reaction.

Aryl–Aryl Bond Formation by the Fluoride‐Free Cross‐Coupling of Aryldisiloxanes with Aryl Bromides

“…For example, a variety of bases have been shown to act as effective activators of silicon-based reagents. [20][21][22][23][24][25][26][27][28] In 2000, Hiyama and co-workers described the fluoride-free palladium-catalysed cross-coupling of organosilanol species with a variety of iodoarenes in the presence of stoichiometric Ag 2 O as an activator. [29] Over the last decade, the field of organosilanol-based cross-coupling has developed rapidly, with significant practical and theoretical contributions being made by Denmark and coworkers.…”

Solvent-Free Synthesis of Siloxanes and their Usage as Potential Cross-Coupling Reagents

“…All the precedents are suffered from at least one of the above drawbacks. On the other hand, cross-coupling reaction starting with cyclotrisiloxane 1 works quite well [4], and target biaryl compounds are obtained in good yields (Scheme 3) [5]. The present reaction is free from all the above-mentioned drawbacks.…”

“…It is noteworthy that this reaction can be applied to the coupling reaction with halophenyl compounds possessing thioanisyl, benzylthio, fluoro, acetyl, and nitro groups, indicating the versatility of this reaction [4].…”