Pentacoordinate silicon compounds: Stereochemical non-rigidity of chelates formed by intramolecular ring-closure. Crystal structure of 8-dimethylamino-1-trifluorosilylnaphthalene
作者:Francis Carré、Robert J.P. Corriu、Agapit Kpoton、Monique Poirier、Gérard Royo、J.Colin Young、Claude Belin
DOI:10.1016/0022-328x(94)80147-9
日期:1994.5
non-rigidity in pentacoordinate chelated organosilicon compounds is described. It is shown that in the compounds Me2iXYZ, non-dissociative ligand permutation at silicon can be distinguished unambiguously from processes associated with rupture of the chelate ring and nitrogen inversion. The crystal and molecular structure of 8-Me2NC10H6SiF3 has been determined. Pentacoordination of the silicon atom is confirmed
描述了动态NMR光谱在五配位螯合有机硅化合物的立体化学非刚性研究中的应用。结果表明,在化合物Me 2 iXYZ中,硅的非解离配体排列可以与螯合环断裂和氮转化相关的过程明确区分。8-Me 2 NC 10 H 6 SiF 3的晶体和分子结构已经确定。确认了硅原子的五配位,供体氮原子和氟原子占据了整个三角双锥体几何结构的轴向位点。所述N个→分离的Si为2.3埃(平均两个不同但密切相关的分子构象的),这是不太比C 1 C 8在萘核的距离,表明相当大键合相互作用。NMR研究Me 2 N基团的动力学行为,并在可能的情况下(19 F,1H)8-二甲基氨基-1-甲硅烷基萘化合物中的单齿配体,与螯合的苄基氨基硅化合物的结果一起,证实通过该方法不能实现硅原子上绝对构型的反转。在硅上非解离配体置换的活化自由能范围从小于7 kcal mol -1 [SiH 3,Si(OR)3 ],低于直接测量的极限,到13 kcal