Photochemical Deoxygenative Hydroalkylation of Unactivated Alkenes Promoted by a Nucleophilic Organocatalyst

Abstract

AbstractThe direct utilization of simple and abundant feedstocks in carbon‐carbon bond‐forming reactions to embellish sp3‐enriched chemical space is highly desirable. Herein, we report a novel photochemical deoxygenative hydroalkylation of unactivated alkenes with readily available carboxylic acid derivatives. The reaction displays broad functional group tolerance, accommodating carboxylic acid‐, alcohol‐, ester‐, ketone‐, amide‐, silane‐, and boronic ester groups, as well as nitrile‐containing substrates. The reaction is operationally simple, mild, and water‐tolerant, and can be carried out on multigram‐scale, which highlights the utility of the method to prepare value‐added compounds in a practical and scalable manner. The synthetic application of the developed method is further exemplified through the synthesis of suberanilic acid, a precursor of vorinostat, a drug used for the treatment of cutaneous T‐cell lymphoma. A novel mechanistic approach was identified using thiol as a nucleophilic catalyst, which forms a key intermediate for this transformation. Furthermore, electrochemical studies, quantum yield, and mechanistic experiments were conducted to support a proposed catalytic cycle for the transformation.