Palladium-catalyzed Aminocarbonylation of Benzylic Chlorides Using Carbamoylsilane as an Amide Source: Efficient Access of Secondary Aryl Acetamides

Abstract

Aim and Objective: Amides are a very important class of organic compounds. As a type of important amides, arylacetamides have gained considerable attention since their pharmacological and biological activities. Therefore, the development of new methods for the synthesis of aryl acetamides is of significant interest among organic chemists. Material and Method: Using N-methoxymethyl-N-methylcarbamoyl(trimethyl)silane as a secondary amide source, the aminocarbonylation of benzylic chlorides by palladium-catalyzed afforded the corresponding protected secondary arylacetamides in good yields under mild reaction conditions. The methoxymethyl group was used as an amino protecting group and can be easily hydrolyzed in acid condition to afford secondary arylacetamides. Results: A novel and highly efficient synthetic method toward secondary arylacetamides by palladium– catalyzed aminocarbonylation of aryl halides was developed using N-methoxymethyl-N-methylcarbamoyl(trimethyl) silane as secondary arylacetamides source, and investigated the scope and limitation of the aminocarbonylation. The relative position of substituent on the aryl ring to influence on this transformation. In this protocol, the methoxymethyl group was used as an amino protecting group and can be easily hydrolyzed. Conclusion: We have investigated the scope and limitation of the aminocarbonylation of benzylic chlorides with carbamoylsilane, expanded to synthesis of secondary arylacetamides using N-methoxymethyl-Nmethylcarbamoyl( trimethyl)silane as a secondary amide source. Keywords: Benzylic chlorides, carbamoylsilane, amides, C–C Coupling, aminocarbonylation, arylacetamides.