Effective Formation of New C(sp2)−S Bonds via Photoactivation of Alkylamine‐based Electron Donor‐Acceptor Complexes

• Published in: Chemistry : a European journal Vol. 29; no. 6; pp. e202203353 - n/a
• Main Authors: Herrera‐Luna, Jorge C., Pérez‐Aguilar, María Carmen, Gerken, Leon, García Mancheño, Olga, Consuelo Jiménez, M., Pérez‐Ruiz, Raúl
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 27-01-2023; John Wiley and Sons Inc
• Subjects: Alkylamines; Chemistry; Complex formation; EDA complex; Halides; heteroarene thiolation; Photoactivation; single-electron transfer; sustainability; visible-light; EDA complex; single-electron transfer; visible-light; heteroarene thiolation; sustainability
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.202203353

A novel visible light promoted formation of CAryl‐S bonds through electron donor‐acceptor (EDA) complexes of alkylamines with 5‐ and 6‐membered (hetero)arene halides is presented. This represents the first EDA‐based thiolation method not relying on π‐π or a thiolate‐anion‐π interactions and provides a facile access to heteroarene radicals, which can be suitably trapped by disulfide derivatives to form the corresponding versatile arylsulfides. Mechanistic investigations on the aspects of the whole process were conducted by spectroscopic measurements, demonstrating the hypothesized EDA complex formation. Moreover, the strength of this method has been proven by a gram‐scale synthesis of thiolated products and the late‐stage derivatization of an anticoagulant drug.
An effective approach for the direct thiolation of five‐membered heteroarenes involving visible‐light‐absorbing EDA complexes is reported. The reaction takes place from an EDA complex between an alkylamine and the heteroarene halide. Selective photolysis to the EDA complex has allowed to generate the heteroarene radical that is suitably trapped by disulfide derivatives, providing a potent synthetic versatility.