Indium-mediated regioselective synthesis of ketones from arylstannanes under solvent-free ultrasound irradiation

Abstract

The solvent-free indium-promoted reaction of alkanoyl chlorides with sterically and electronically diverse arylstannanes is a simple and direct method for the regioselective synthesis of primary, secondary and tertiary alkyl aryl ketones in good to excellent isolated yields (42-84%) under mild and neutral conditions. The protocol is also adequate for the synthesis of aryl vinyl ketones. Reaction times are drastically reduced (from 3-32h to 10-70min) under ultrasonic irradiation. Evidences for the involvement of a homolytic aromatic ipso-substitution mechanism, in which indium metal acts as radical initiator, are presented. It is possible the transference of two aryl groups from tin, thus improving effective mass yield, working with diarylstannanes as starting substrates.

Merging Metallic Catalysts and Sonication: A Periodic Table Overview

“…20 h to afford similar results. Arylstannanes (30) have been recently employed as useful partners with alkanoyl chlorides (31) in an indium-mediated regioselective synthesis of alkyl aryl ketones (32) (Scheme 10) [37]. The protocol also works for aryl vinyl ketones.…”

“…Yields were moderate to good (42%-84%) and, remarkably, the transformation can be run under neat conditions, without requiring an organic solvent. Sonication dramatically reduced the reaction times compared to conventional conditions Arylstannanes (30) have been recently employed as useful partners with alkanoyl chlorides (31) in an indium-mediated regioselective synthesis of alkyl aryl ketones (32) (Scheme 10) [37]. The protocol also works for aryl vinyl ketones.…”

Use of Ultrasound in the Synthesis of Heterocycles of Medicinal Interest

“…This technique has become extremely popular in promoting various chemical reactions since the decade 1990-1999 [22][23][24][25][26][27][28]. In recent years, the effect of ultrasonic energies in organic synthesis (homogeneous and heterogeneous reactions) has widely increased [30][31][32][33][34][35][36][37][38]. In recent years, the effect of ultrasonic energies in organic synthesis (homogeneous and heterogeneous reactions) has widely increased [30][31][32][33][34][35][36][37][38].…”

Sonochemical synthesis of 5-substituted 1H-tetrazoles catalyzed by ZrP2O7 nanoparticles and regioselective conversion into new 2,5-disubstituted tetrazoles

“…Ultrasonically accelerated organic synthesis has received significant attention in recent years [1,2]. The strategy of ultrasound as an energy source offers major advantages to promote organic reactions in the form of design and development [3,4].…”