Stoichiometric and catalytic C-F bond activation by the trans-dihydride NHC complex [Ru(IEt2Me2)2(PPh3)2H2] (IEt2Me2 = 1,3-diethyl-4,5-dimethylimidazol-2-ylidene).
Stoichiometric and catalytic C-F bond activation by the trans-dihydride NHC complex [Ru(IEt2Me2)2(PPh3)2H2] (IEt2Me2 = 1,3-diethyl-4,5-dimethylimidazol-2-ylidene).
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DOI：
10.1039/c5dt01996f
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发表时间：
2015-11
影响因子：
4
通讯作者：
Mateusz K. Cybulski;Ian M. Riddlestone;M. Mahon;Timothy J. Woodman;M. Whittlesey
中科院分区：
文献类型：
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作者：
Mateusz K. Cybulski;Ian M. Riddlestone;M. Mahon;Timothy J. Woodman;M. Whittlesey
C6F6或C6F5H与[Ru(IEt2Me2)2(PPh3)2H2](；IEt2Me2=1，3-二乙基-4，5-二甲基咪唑-2-亚甲基)在室温下反应生成反式氟化物配合物[Ru(IEt2Me2)2(PPh3)2HF]()和双卡宾五氟苯基物种[Ru(IEt2Me2)2(PPh3)(C6F5)H]()。C6F5H的形成是由于C6F5H(由C6F6通过化学计量加氢脱氟形成)的C-H活化所致，这一过程可以在4个大气压的H2下工作来逆转。用C6F5H加热，得到双膦衍生物[Ru(IEt2Me2)(PPh3)2(C6F5)H]()。一个更有效的途径，涉及治疗与0.33 eq。过量试剂给出已知阳离子[Ru(IEt2Me2)2(PPh3)2H](+)的[H2F3](-)盐()。在催化条件下，以Et3SiH为还原剂，在363K下将C6F6转化为三氟、二氟和一氟苯混合物(TON=37)，是一种活性的加氢脱氟前驱体。
The room temperature reaction of C6F6 or C6F5H with [Ru(IEt2Me2)2(PPh3)2H2] (; IEt2Me2 = 1,3-diethyl-4,5-dimethylimidazol-2-ylidene) generated a mixture of the trans-hydride fluoride complex [Ru(IEt2Me2)2(PPh3)2HF] () and the bis-carbene pentafluorophenyl species [Ru(IEt2Me2)2(PPh3)(C6F5)H] (). The formation of resulted from C-H activation of C6F5H (formed from C6F6via stoichiometric hydrodefluorination), a process which could be reversed by working under 4 atm H2. Upon heating with C6F5H, the bis-phosphine derivative [Ru(IEt2Me2)(PPh3)2(C6F5)H] () was isolated. A more efficient route to involved treatment of with 0.33 eq. of TREAT-HF (Et3N·3HF); excess reagent gave instead the [H2F3](-) salt () of the known cation [Ru(IEt2Me2)2(PPh3)2H](+). Under catalytic conditions, proved to be an active precursor for hydrodefluorination, converting C6F6 to a mixture of tri, di and monofluorobenzenes (TON = 37) at 363 K with 10 mol% and Et3SiH as the reductant.