Triflate‐Selective Suzuki Cross‐Coupling of Chloro‐ and Bromoaryl Triflates Under Ligand‐Free Conditions
Triflate‐Selective Suzuki Cross‐Coupling of Chloro‐ and Bromoaryl Triflates Under Ligand‐Free Conditions
复制标题
三氟甲磺酸酯 — 选择性铃木交叉 — 配体自由条件下氯代三氟甲磺酸酯和溴芳基三氟甲磺酸酯的偶联
DOI：
10.1002/asia.202300036
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Neufeldt, Sharon R.
中科院分区：
文献类型：
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作者：
Ibsen, Grace M.;Menezes da Silva, Vitor H.;Pettigrew, J. Cole;Neufeldt, Sharon R.
在没有强的辅助配体如膦或N-杂环卡宾的情况下，钯盐在氯芳基三氟甲磺酸酯在乙腈中的室温Suzuki偶联中对C−OTf裂解具有选择性。DMSO中类似的“无配体”条件也促进溴芳基三氟甲磺酸酯的三氟甲磺酸酯选择性Suzuki偶联。这种三氟甲磺酸酯选择性补充了在使用膦配体的Suzuki偶联的先前报道中对溴化物反应的典型偏好。DFT计算和额外的实验证据与三氟甲磺酸酯选择性氧化加成在由溶剂分子支撑的均匀的、可能单核的阴离子钯上发生一致。
In the absence of strong ancillary ligands such as phosphines orN‐heterocyclic carbenes, palladium salts are selective for C−OTf cleavage in the room‐temperature Suzuki couplings of chloroaryl triflates in acetonitrile. Similar “ligand‐free” conditions in DMSO also promote triflate‐selective Suzuki coupling of bromoaryl triflates. This triflate selectivity complements the typical preference for reaction of bromides in prior reports of Suzuki couplings using phosphine ligands. DFT calculations and additional experimental evidence are consistent with triflate‐selective oxidative addition taking place at homogeneous, possibly mononuclear, anionic palladium supported by a solvent molecule.