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Abstract
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Carbamates are an important class of organic compounds due to having pharmacological properties such as antibiotic, fungicide, insecticide, and herbicide. Traditionally, synthesis of these compounds is done via the reaction of amines with phosgene or its derivatives. Copper-catalyzed cross-dehydrogenative coupling (CDC) reaction of formamides with suitable precursors for the synthesis of carbamates has been well studied. In 2011, Reddy et al. reported the synthesis of enol carbamates and 2-carbonyl-substituted phenol carbamates via the oxidative-coupling of formamides with ?-dicarbonyl compounds or ortho-substituted phenolic compounds. Moreover, copper catalyzed oxidative-coupling of formamides with 2-substituted phenols have already been reported for synthesis of carbamates. In this line of research, we have found out that Ni can be an effective catalyst for the above-mentioned transformations. Thus, NiCl2, a cheap and readily available salt, was used as the catalyst for the synthesis of carbamates providing milder reaction conditions than copper in these reactions
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