Isolation of silenolates (R3Si)2Si=C(OLi)Ad with a doubly bonded silicon atom

Angewandte Chemie - International Edition

Volumn 49, Issue 24, 2010, Pages 4084-4087

  Dobrovetsky, Roman ^a   Zborovsky, Lieby ^a   Sheberla, Dennis ^a   Botoshansky, Mark ^a   Bravo Zhivotovskii, Dmitry ^a   Apeloig, Yitzhak ^a  

^a TECHNION ISRAEL INSTITUTE OF TECHNOLOGY   (Israel)

Author keywords

Density functional calculations; Enols; Silenes silicon; Tautomerism

Indexed keywords

DENSITY-FUNCTIONAL CALCULATIONS; ENOLATES; ENOLS; NON-POLAR SOLVENTS; SILENES; SILICON ATOMS;

SYNTHESIS (CHEMICAL); X RAY SPECTROSCOPY;

SILICON;

EID: 77953117692     PISSN: 14337851     EISSN: 15213773     Source Type: Journal    
DOI: 10.1002/anie.201001024     Document Type: Article

References (35)

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23. 3)Ad (1.801 Å) is 0.01.5 Å longer than the calculated value of 5 (1.786 Å).
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25. max. = 25°, R = 0.0872 [I> 2σ(I)], wR2 = 0.2122 [I>2σ(I)], RW = 0.1937 (all data), GOF = 0.986. CCDC 760802 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data-request/cif.
26. Compound 2 was crystallized from hexane; however, after precipitation. 2 is not soluble in hexane or benzene, and in THF it undergoes chemical transformation; therefore, its solution NMR spectra could not be measured.
27. The Gaussian 03 series of programs was used. All molecules were fully optimized at the B3LYP 6-31G + (d) level of theory and all structures were confirmed as local minima by calculating second order derivatives. For full details see Supporting Information.
28. Partially reported by us at the 15th International Symposium on Organosilicon Chemistry (ISOS-XV), Jeju, South Korea, June 1-6, 2008, Book of abstracts, 162.
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34. In all calculated molecules a minimum in which Li is bonded to Si was not found. We are well aware that the B3LYP functional tends to overestimate the degree of pyramidalization at silicon (I. Bejan, D. Güclü, S. Inoue, M. Ichinohe, A. Sekiguchi, D. Scheschkewitz, Angew. Chem. 2007, 119, 3413-3416;
35. Angew. Chem. Int. Ed. 2007, 46, 3349-3352). However, the calculated geometries of the silenolates are in good agreement with the experimental, geometries of 1, 2, and 6.