Stable N-Heterocyclic Carbene Adducts of Arylchlorosilylenes and Their Germanium Homologues
Stable N-Heterocyclic Carbene Adducts of Arylchlorosilylenes and Their Germanium Homologues
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DOI：
10.1002/chem.200903019
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发表时间：
2010-01-01
影响因子：
4.3
通讯作者：
Schnakenburg, Gregor
中科院分区：
文献类型：
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作者：
Filippou, Alexander C.;Chernov, Oleg;Schnakenburg, Gregor
报道了第一个芳基氯代硅烯的N-杂环卡宾加合物，并与同系锗化合物进行了比较。以1，3，4，5-四甲基咪唑-2-亚基（Im-Me-4）为原料，选择性地使芳基氯硅烷SiArHCl 2脱氯化氢，得到芳基氯化硅SiArCl（Im-Me-4）[Ar= C6 H3 - 2，6-Mes（2）（Mes= C6 H2 - 2，4，6-Me-3），C6 H3 - 2，6-Trip（2）（Trip= C6 H2 - 2，4，6-iPr（3）]。类似的芳基锗（II）氯化物GeArCl（Im-Me-4）通过GeCl 2（Im-Me-4）与LiC 6 H3 - 2，6-Mes（2）的复分解交换或Im-Me-4与GeCl（C6 H3 - 2，6-Trip（2））的加成来制备。对所有化合物进行了充分表征。在不同的理论水平上对ECl（C6 H3 - 2，6-Trip（2））（Im-Me-4）（其中E = Si，Ge）的密度泛函计算表明，计算的成键参数与实验的成键参数之间有很好的一致性，NBO分析揭示了两种芳基四元（II）氯化物相似的电子结构。SiCl（C_6H_3 - 2，6-Trip（2））（Im-Me-4）的低气相吉布斯自由能（Δ G（计算）度=28.1 kJ mol（-1））表明，卡宾加合物SiArCl（Im-Me-4）可能是芳基硅（II）氯化物SiArCl的有价值的转移试剂。
The first N-heterocyclic carbene adducts of arylchlorosilylenes are reported and compared with the homologous germanium compounds. The arylsilicon(II) chlorides SiArCl(Im-Me-4) [Ar=C6H3-2,6-Mes(2) (Mes=C6H2-2,4,6-Me-3), C6H3-2,6-Trip(2) (Trip=C6H2-2,4,6-iPr(3))] were obtained selectively on dehydrochlorination of the arylchlorosilanes SiArHCl2 with 1,3,4,5-tetramethylimidazol-2-ylidene (Im-Me-4). The analogous arylgermanium(II) chlorides GeArCl(Im-Me-4) were prepared by metathetical exchange of GeCl2(Im-Me-4) with LiC6H3-2,6-Mes(2) or addition of Im-Me-4 to GeCl(C6H3-2,6-Trip(2)). All compounds were fully characterized. Density functional calculations on ECl(C6H3-2,6-Trip(2))(Im-Me-4), where E = Si, Ge, at different levels of theory show very good agreement between calculated and experimental bonding parameters, and NBO analyses reveal similar electronic structures of the two aryltetrel(II) chlorides. The low gas-phase Gibbs free energy of bond dissociation of SiCl(C6H3-2,6-Trip(2))(Im-Me-4) (Delta G(calcd)degrees=28.1 kJ mol(-1)) suggests that the carbene adducts SiArCl(Im-Me-4) may be valuable transfer reagents of the arylsilicon(II) chlorides SiArCl.