"On water" palladium catalyzed diastereoselective boronic acid addition to structurally diverse cyclopropane nitriles
Dwaipayan Das1, Prasun Mukherjee, Asish R Das
1Department of Chemistry, University of Calcutta 92, A. P. C. Road, Kolkata-700009, India. ardchem@caluniv.ac.in ardas66@rediffmail.com.
Abstract:
An efficient palladium catalyzed diastereoselective addition of arylboronic acids to complex spirocyclopropyl dinitriles is developed in the presence of a catalytic amount of 4-dodecylbenzenesulphonic acid (DBSA) as a Brønsted acid surfactant in aqueous media. The protocol is also found to be highly effective when different types of nitrile compounds and organo-boron compounds are used. The overall reaction has been found to be very cost efficient since it requires low catalyst loading, mild thermal energy and short reaction time. Wide substrate scope, operational simplicity, good to excellent product yield, and use of green solvents make the reaction a practical route to transform nitrile into a keto functionality in biorelevant heterocyclic scaffolds. The scale-up synthesis of the target scaffolds can also be achieved with ease which also signifies the practicability of this protocol.
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