STRACTURAL INVESTIGATION OF GRIGNARD REAGENTS BY MEANS OF SPRAY IONIZATION MASS SPECTROMETRY AND RAPID X-RAY CRYSTALLOGRAPHY

冷ESI，在低温下的操作最近在我们的实验室开发，并确保保持热不稳定的化合物无法改变。使用冷ESI解决方案在四氢呋喃（THF）中获得的MeMgCl、MeMgBr、EtMgCl、EtMgCl t-BuMgCl、AllyMgCl和i-PrMgCl中的一些重要特性。The characteristic ion peaks consistent with these three spectra of m/z528， 601 and 673 indicate the ion species of [NMgイイD22イイD2ClイD23イイD2（THF）イD2nイD2]イD1+イD1 formed based on the atomic n·gen attached break down products。The [RMg_D22__同位素离子峰值模式作为MS/MS分析从父母离子建议这些离子结构中检测序列THF清除。Following equilibrium is then derived.3 RMgX（THF） ... More D2 （如1）在另一方，X射线晶体学分析是不可接受的。We determined the cr？structures of 2[Mg？D22？D23？D2（THF）？D26？D2（THF）] from t-BuMgCl. Dimagnesium Cationic Species的结构包括在两种晶体中发现的PhMgCl和t-BuMgCl都已解决。This cationic species [MgイD22イイD2ClイD23イD2（THF）イD26イD2]イD1+イD1 which is detected in the Grignard reagent for the first time has rarely observed。第一个没有RMgX的溶剂分子被观察到的晶体结构。在从t-BuMgCl、单体结构（t-BuMgClyy D22-D2 THF）中发现的晶体与文化物种一起可见。These constitutions were thought to be included in the Schlenk equilibrium.8 PhMgCl（THF）イD2nイD2 [double row] 2 PhイD22イD2Mg + 2[MgイD22イD2ClイD2]イD26イD1 + [PhイD24イD2MgイD22イD2]イD12-イD1 （eq. 2）5 t-BuMgCl（THF）イイD2nイエD2 [double row] 2 t-BuMgCl D22イエD2Mg + [（MgイD22イイD23イD2）（THF）イD26イイD1 + [t-BuMgClイD22イエD2（THF）]イD1-イD1 （eq.（3）格里格纳德物种的其他水晶结构也在相同的标准中被调查。In case of MeMgCl， the cr？structure of Me D22 Mg D24 Mg D22 Mg D26 Mg D26 Mg D26 Mg D26 Mg D2（THF）D26 Mg + Me D26 Mg D2（THF）D26 Mg D2 （eq.（c）减

The cold ESI, operating ionization under low temperature was recently developed in our laboratory and proved to be effective to preserve thermally unstable compounds unchanged. Some significant spectra were obtained form MeMgCl, MeMgBr, EtMgCl, EtMgBr, PhMgCl t-BuMgCl, AllyMgCl and i-PrMgCl in tetrahydrofuran (THF) solution using the cold ESI. The characteristic ion peaks consistent with these three spectra of m/z 529, 601 and 673 indicate the ion species of [NMgィイD22ィエD2ClィイD23ィエD2(THF)ィイD2nィエD2]ィイD1+ィエD1 formed based on the atomic nitrogen attached break down products. The [RMgィイD22ィエD2ClィイD23ィエD2(THF)ィイD2nィエD2-H]ィイD1+ィエD1 ion peaks directly related to the corresponding Grignard species are definitely observed in EtMgCl and PhMgCl. The isotopic ion peak patterns as well as MS/MS analysis detecting sequential THF cleavage from the parent ion suggest these ion structures. Following equilibrium is then derived.3RMgX(THF)ィイD2nィエD2【double arrow】RィイD22ィエD2Mg + RMgィイD22ィエD2XィイD23ィエD2(THF)ィイ … More D2nィエD2 (eq.1)On the other hand, X-ray crystallographic analyses were undertaken. We determined the crystal structures of 2[MgィイD22ィエD2ClィイD23ィエD2(THF)ィイD26ィエD2]・[PhィイD24ィエD2MgィイD22ィエD2ClィイD22ィエD2] obtained from PhMgCl, and [MgィイD22ィエD2ClィイD23ィエD2(THF)ィイD26ィエD2]・[t-BuMgClィイD22ィエD2(THF)] from t-BuMgCl. The structure of dimagnesium cationic species included in the both crystals obtained from PhMgCl and t-BuMgCl was solved. This cationic species [MgィイD22ィエD2ClィイD23ィエD2(THF)ィイD26ィエD2]ィイD1+ィエD1 which is detected in the Grignard reagent for the first time has rarely observed. The first crysta lstructure of RMgX without solvent molecule was observed. In case of the crystal obtained from t-BuMgCl, monomeric structure (t-BuMgClィイD22ィエD2THF) was observed together with the cationic species. These constitutions were thought to be included in the Schlenk equilibrium.8PhMgCl(THF)ィイD2nィエD2 【double arrow】2PhィイD22ィエD2Mg + 2[(MgィイD22ィエD2ClィイD23ィエD2)(THF)ィイD26ィエD2]ィイD1+ィエD1 + [PhィイD24ィエD2MgィイD22ィエD2ClィイD22ィエD2]ィイD12-ィエD1 (eq. 2)5t-BuMgCl(THF)ィイD2nィエD2 【double arrow】 2t-BuィイD22ィエD2Mg + [(MgィイD22ィエD2ClィイD23ィエD2)(THF)ィイD26ィエD2]ィイD1+ィエD1 + [t-BuMgClィイD22ィエD2(THF)]ィイD1-ィエD1 (eq. 3)Other crystal structures of Grignard species have also been investigated in the same manner for comparison. In case of MeMgCl, the crystal structure of MeィイD22ィエD2MgィイD24ィエD2ClィイD26ィエD2(THF)ィイD26ィエD2 included in Schlenk equilibrium was found.6MeMgCl(THF)ィイD2nィエD2 【double arrow】 2MeィイD22ィエD2Mg + MeィイD22ィエD2MgィイD24ィエD2ClィイD26ィエD2(THF)ィイD26ィエD2 (eq. 4) Less