Synthesis and Structural Characterization of Functional Bicyclic Intramolecularly Coordinated Aminoarylsilanes in a Series of Dibenzyl(1,5)azasilocines
| Autor: | and Florence Soulairol, Francis Carré, Gérard F. Lanneau, Robert J. P. Corriu, Jiachang Yao, Philippe Merle |
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| Rok vydání: | 1997 |
| Předmět: | |
| Zdroj: | Organometallics. 16:3878-3888 |
| ISSN: | 1520-6041 0276-7333 |
| DOI: | 10.1021/om970361w |
| Popis: | A new synthetic approach to functional eight-membered silicon-containing heterocycles has been developed. The intramolecular coordination of chelated aminoaryl ligands, −o-C6H4−CH2−N(R)−CH2−C6H4-o−, with R = t-Bu, i-Pr, PhCH2, results in rigid molecules of the = Y = H, OMe, F and X = H, Y = F, Cl, Br, I, OMe, OTf). Two types of molecules are characterized in the refined structure Pentacoordination of the silicon atom is observed, with the donor atom and one fluorine atom occupying axial sites in an overall trigonal bipyramidal geometry (N−Si average distance of 2.43 A). Stereodynamic rearrangements in solution are deduced from the NMR spectral data. Equivalence of the CH2 benzylic protons (an AB system at low temperature) implies an inversion at the nitrogen atom. The activation parameters for a dissociative mechanism have been calculated, following variable-temperature NMR measurements with different probes. The activation energy barriers of the isomerization process are strongly dependent on the functio... |
| Databáze: | OpenAIRE |
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