via conventional or microwave heating. The 1H NMR spectra of the benzyl-substituted species 1c and 1d showed signals for diastereotopic NCH2CH2S protons at room temperature. However, structural studies established the absence of coordination of the sulphur atom in the solid state, and solvent DFT calculations showed that bromide displacement by sulphur is an unfavourable process (ΔG = +13.5 kcal mol−1
                                    中性
镍的N-杂环卡宾配合物,(κ 1 - C ^) - [NiCpBr R-NHC-(CH 2)2 SR'}]的[Cp =η 5 -C 5 H ^ 5 ; R-NHC-(CH 2)2 SR'= 1-甲三醇-3- [2-(叔丁
硫基)乙基]-(1a),1-甲三醇-3- [2-(苯
硫基)乙基]-(1b),1-苄基-3- [2-(叔丁
硫基)乙基]-(1c),1-苄基-3- [2-(苯
硫基乙基)]-
咪唑-2-亚基(1d)]一个ñ通过新星与相应的
咪唑鎓
溴化物[R-NHC-(CH 2)2 SR'·HBr](a-d)反应,通过常规或微波加热制备结合有
硫醚的侧臂。苄基取代的物种1c和1d的1 H NMR光谱显示室温下非对位NCH 2 CH 2 S质子的信号。然而,结构的研究确立了不存在在固体状态中的
硫原子的配位的,和溶剂DFT计算表明,
溴化物位移由
硫是不利的过程(Δ G ^ = 13.5千卡摩尔-1为1d