A New Family of Nucleophiles for Photoinduced, Copper-Catalyzed Cross-Couplings via Single-Electron Transfer: Reactions of Thiols with Aryl Halides Under Mild Conditions (O degrees C)

作者：Uyeda, Christopher; Tan, Yichen; Fu, Gregory C.^*; Peters, Jonas C.

来源：Journal of the American Chemical Society, 2013, 135(25): 9548-9552.

DOI：10.1021/ja404050f

• X-RAY CRYSTAL
• BOND FORMATION
• METALLOTHIONEIN
• EFFICIENT
• PHOTOPHYSICS
• LUMINESCENCE
• ABSORPTION
• ARYLATION
• COMPLEXES
• PALLADIUM

Building on the known photophysical properties of well-defined copper-carbazolide complexes, we have recently described photoinduced, copper-catalyzed N-arylations and N-alkylations of carbazoles. Until now, there have been no examples of the use of other families of heteroatom nucleophiles in such photoinduced processes. Herein, we report a versatile photoinduced, copper-catalyzed method for coupling aryl thiols with aryl halides, wherein a single set of reaction conditions, using inexpensive CuI as a precatalyst without the need for an added ligand, is effective for a wide range of coupling partners. As far as we are aware, copper-catalyzed C-S cross-couplings at 0 degrees C have not previously been achieved, which renders our observation of efficient reaction of an unactivated aryl iodide at -40 degrees C especially striking. Mechanistic investigations are consistent with these photoinduced C-S cross-couplings following a SET/radical pathway for C-X bond cleavage (via a Cu(I)-thiolate), which contrasts with nonphotoinduced, copper-catalyzed processes wherein a concerted mechanism is believed to occur.

• 出版日期2013-6-26