Bis(imino)acenaphthene (BIAN)-Supported N-Heterocyclic CarbenePalladium Complexes with Ancillary Ligands: Readily ActivatedPrecatalysts for Direct C-H Arylation of Thiophenes

作者：Zheng, Di-Zhong; Li, Dong-Hui; Liu, Huan; Shao, Youxiang; Ke, Zhuofeng^*; Liu, Feng-Shou^*

来源：Organometallics, 2022, 41(8): 948-961.

DOI：10.1021/acs.organomet.2c00007

• N-HETEROCYCLIC CARBENE
• CATALYZED DIRECT ARYLATION
• METALATION-DEPROTONATION MECHANISM
• GENERAL SYNTHETIC ROUTE
• PD-PEPPSI COMPLEXES
• PALLADIUM COMPLEXES
• HIGHLY EFFICIENT
• BOND ARYLATION
• ARYL BROMIDES
• DIRECT (HETERO)ARYLATION

We report herein a highly efficient direct C-H arylation ofthiophenes with (hetero)aryl bromides by bulky bis(imino)acenaphthene (BIAN)-supportedN-heterocyclic carbene palladium complexes. The relationship betweenthe structure of palladium complexes with ancillary ligands and catalytic propertieswas discussed. Upon a low palladium loading of 0.01-0.05 mol %, the bulkypalladium complex was successfully used to catalyze the cross-coupling of a variety ofthiophens with (hetero)aryl bromides under aerobic conditions. Furthermore, itprovides a practical and straightforward access to poly(3-hexylthiophenes) with highmolecular weight and high HT value under aerobic reaction conditions. To accessthe mechanistic of the transformation, experiment investigation and DFTcalculations on the direct arylationwere performed, which supported theinvolvement of a Pd(0)/Pd(II)CMD process.

• 单位
  广东药学院; 中山大学