Synthesis, structure, and stereochemical non-rigidity of bis[(2,2-dimethyl-4-oxo-2H-benzo[e][1,3]oxazin-3(4H)-yl)methyl] dichlorosilane and -germane

• Published in: Russian chemical bulletin 2015-08, Vol.64 (8), p.1808-1813
• Main Authors: Negrebetsky, Vad. V., Kramarova, E. P., Arkhipov, D. E., Korlyukov, A. A., Shipov, A. G., Baukov, Yu. I.
• Format: Article
• Language: English
• Subjects: Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Full Articles; Inorganic Chemistry; Organic Chemistry
• ISSN: 1066-5285; 1573-9171
• DOI: 10.1007/s11172-015-1075-3

Bis[(2,2-dimethyl-4-oxo-2 H -benzo[ e ][1,3]oxazin-3(4 H )-yl)methyl]dichlorosilane ( 1 ) and -germane ( 2 ) were synthesized by the reaction of 2,2-dimethyl-3-(trimethylsilyl)-2 H -benzo[e][1,3]oxazin-3(4 H )-one with bis(chloromethyl)dichlorosilane and -germane, respectively, taken in a ratio of 2 : 1. The structures of these compounds were determined and their stereodynamic behavior in solution was studied by multinuclear ( 1 H, 13 C, and 29 Si) and twodimensional ( 1 H, 13 C COSY, HETCOR) NMR spectroscopy. The 29 Si NMR spectroscopic study of a solution of complex 1 provides evidence that the silicon atom in this complex is pentacoordinate. The X-ray diffraction study showed that the germanium atom in complex 2 in the solid state is hexacoordinate. The permutation isomerization in the coordination units of complexes 1 and 2 was found and investigated by dynamic 1 H NMR spectroscopy. Different mechanisms of stereodynamic transformations are suggested and discussed.