A Fast and Additive Free C–C Homo/Cross‐Coupling Reaction in Reverse Micelle: An Understanding of Role of Surfactant, Water Content and Base on the Product Yield and Reaction Site

Abstract

A fresh modus operandi was designed for additive and ligand free transition metal‐catalyzed C−C homo/cross‐coupling reactions of arylboronic acid in reverse micellar (RMs) templates. Three RMs based on different charge types of polar head groups and length of hydrophobic moieties of surfactants [e. g., anionic (AOT), cationic (DDAB), and non‐ionic (TX 100)] in cyclohexane were chosen herein. The reaction proceeded rapidly in these RMs and completed within 10 minutes at ambient condition. Performance of reaction in terms of yield of the desired product in RMs, was correlated with various physicochemical parameters of these systems as obtained from conductance, DLS and FTIR techniques. The results revealed that AOT is best suited for further studies. The progress of the reaction with time was monitored in AOT RMs as supplementary study by using above mentioned methods. It was emphasized that types of base and catalyst, water content influenced the product yield and plausible reaction location. Finally, the development of a series of symmetrical and unsymmetrical biaryl via above reaction in AOT RM was explored successfully.

Structural Transitions at the Water/Oil Interface by Ionic-Liquid-like Surfactant, 1-Butyl-3-methylimidazolium Dioctyl Sulfosuccinate: Measurements and Mechanism

“…The C–C coupled moieties are often seen in various bioactive molecules. Reverse micelles, having water droplets dispersed in bulk oil medium, can uptake both polar and apolar molecules and also provide a confined environment for in situ reactions. ,− Here we examined the suitability of our water/[BMIM]­[AOT]/IPM system as a medium for Heck reaction, i.e., the cross-coupling reaction between para -iodotolune and butylaccrylate in the presence of lead acetate as catalyst (Scheme S3). First, we optimized the reaction by choosing the right base among K 2 CO 3 , tetramethyl ethylene diamine, and triethyl amine (TEA) in the RM environment with w 0 = 20.…”

tert‐Butyl Hydroperoxide Promoted Pd‐catalyzed Homocoupling of Arylboronic Acids

“…A range of additives such as, 1,3‐bis(diphenylphosphino) propane, p ‐toluenesulfonyl chloride, phase transformation catalysts, 2‐propanol, isopropyl myristate and 2,2,6,6‐tetramethylpiperidine‐1‐oxyl have been found to improve the efficiency of this homo‐coupling process. Ionic liquid, supercritical carbon dioxid and reverse micelle have also been used as suitable solvents to promote the homo‐coupling reaction. In addition to homogeneous Pd catalysts, Cr, Rh, Ni, Au and Cu, and heterogeneous palladium catalysts have also exhibited catalytic activity in these boronic acid homocoupling reactions.…”