Ru(II)-Catalyzed ortho-Vinylation of Benzoic Acids in Water
Lalit Negi1, Aditi Soni1, Deepak Sharma1
1Department of Chemistry, Malaviya National Institute of Technology Jaipur, Jaipur 302017, Rajasthan, India.
Abstract:
Herein, we report an efficient [Ru(η6-C6H6)Cl2]2 catalyzed oxidative C-H alkenylation of benzoic acid in the green solvent water. A regioselective olefination of benzoic acid with functionalized alkenes like styrene and acrylate was established at a very mild condition of 60 °C temperature and in an aqueous medium. In contrast to the cyclization of the carboxylic group, a selective ortho-olefination product of benzoic acid was observed with the acrylate. Moreover, a selective formation of mono-olefinated products were observed with activated olefins (acrylate), while mono and diolefinated products were recorded with unactivated olefins (styrene). In contrast to the reactivity of acrylates and styrenes, a fruitful development and formation of a novel five-member cyclic ring, i.e., the (Z)-3-ferrocenylideneisobenzofuran-1(3H)-one, was observed when vinylferrocene was considered as a coupling partner for the reaction.
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