Crystal structures of two polycyclic compounds containing 7-metalonorbornene (silicon and germanium) units

摘要: In our research in organometallic cycloaddition chemistry, we have studied Diels-Alder reactions of 1-sila-2, 5-diphenyl-1, 1-dimethyl-2, 4-cyclopentadiene, 3, 4, 5-tetraphenyl-1, 4-cyclopen tadiene and 1-germa-2, 4-cyclopentadiene as reactive dienes under high pressure. These react readily with 7-oxanorbornene 7-oxabenzonorbornadiene double bond form polycyclic compounds containing 7-metalonorbornene (silicon or germanium) moieties. Stereochemistry the additions was established by crystallographic study adducts 1 2 to be exo, endo-. Diffracted intensities were collected on Oxford Diffraction Xcalibur 3 diffractometer using graphite-monochromated MoKα radiation at 100 K. Data reduction performed CrysAlis software package. The structures solved direct methods (SHELXS) refined full-matrix least-squares method based F2 against all reflections (SHELXL). All non-hydrogen atoms anisotropically. Hydrogen placed geometrically.