Interaction of the Walsh Orbitals in Bicyclopropyl

✍ Scribed by Dipl.-Chem. Peter Asmus; Prof. Dr. Martin Klessinger

• Publisher: John Wiley and Sons
• Year: 1976
• Tongue: English
• Weight: 228 KB
• Volume: 15
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/anie.197603101

✦ Synopsis

Composition and structure of (2) were proved by chemical analysis, mass spectrum, NMR data (31P[41, 'H, "Si) and by complete X-ray structure analysis.

The 'H-NMR spectrum (10% solution in CH2C12; TMS int.[*], 25°C) shows three groups of signals with equal intensity-{ 31P} : three singlets-which indicate sterically fixed bis(trimethylsily1)amino groups. G(>NSiH)= -0.08 ppm (t), 4JHp = 0.55 Hz -N/SiCH = -0.26 ppm (t) [6], I4JHp + 6JHpl = 3.80 Hz ( \SiCH)= -0.52 ppm (s) High-temperature 'H-NMR measurements (10 % solution in HMPT) do not show significant changes in the spectrum up to 240°C (decomposition) and indicate an extremely high barrier of rotation around the phosphorus-nitrogen bond (AG& > 27 kcal/mol).

In the "Si-('H)-FTNMRspectrum(l0 % solution in C6F6;