Scalable α-Arylation of Nitriles in Aqueous Micelles using Ultrasmall Pd Nanoparticles: Surprising Formation of Carbanions in Water
Manisha Bihani, Tharique N. Ansari, Lucie Finck, Pranjal P. Bora, Jacek B. Jasiński, Bhavana Pavuluri, David K. Leahy, Sachin Handa
Abstract
A scalable synthetic method is described for both the preparation of ultrasmall palladium nanoparticles and their subsequent use in catalyzing an α-arylation reaction of nitriles in aqueous micelles. This method involves the intermediacy of carbanions or keteniminates, which are presumably stabilized by the micellar environment rather than being quenched with water. These Pd nanoparticles are thoroughly characterized. Mechanistic studies using 31P NMR spectroscopy revealed the binding of phosphine ligand with the Pd surface and control experiment confirmed the zero-oxidation state of palladium. The scope of the transformation is demonstrated over 35 examples, including one at 50 g scale.