Reversible transformation between a diaminosilylene and a novel disilene [17]

Journal of the American Chemical Society

Volumn 121, Issue 40, 1999, Pages 9479-9480

  Schmedake, Thomas A ^a   Haaf, Michael ^a   Apeloig, Yitzhak ^b   Müller, Thomas ^c   Bukalov, Sergey ^d   West, Robert ^a  

^a UNIVERSITY OF WISCONSIN MADISON   (United States)

^b TECHNION ISRAEL INSTITUTE OF TECHNOLOGY   (Israel)

^c GOETHE UNIVERSITY   (Germany)

^d A N NESMEYANOV INSTITUTE OF ORGANOELEMENT COMPOUNDS   (Russian Federation)

Author keywords

[No Author keywords available]

Indexed keywords

DIAMINOSILYLENE; DIMER; DISILENE; SILANE DERIVATIVE; UNCLASSIFIED DRUG;

CHEMICAL REACTION; CHEMICAL REACTION KINETICS; CHEMICAL STRUCTURE; DIMERIZATION; LETTER; MOLECULAR MODEL; REACTION ANALYSIS; STRUCTURE ANALYSIS;

EID: 0033552249     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja992150j     Document Type: Letter

References (23)

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2. Denk, M.; Green, J. C.; Metzler, N.; Wagner, M. J. Chem. Soc., Dalton Trans. 1994, 2405.
3. Tsutsui, S.; Sakamoto, K.; Kira, M. J. Am. Chem. Soc. 1998, 120, 9955.
4. Apeloig, Y.; Müller, T. J. Am. Chem. Soc. 1995, 117, 5363.
5. 3, R(F) = 0.0406 for 4896 observed reflections. All non-hydrogen atoms were refined with anisotropic displacement parameters. Full crystallographic information is given in the Supporting Information.
6. (a) Schäfer, A.; Saak, W.; Weidenbruch, M. Z. Anorg. Allg. Chem. 1998, 624, 1405.
7. (b) Schäfer, A.; Saak. W.; Weidenbruch, M. Chem. Ber./Recueil 1997, 130, 1733.
8. (c) Weidenbruch, M. Eur. J. Inorg. Chem. 1999, 373.
9. (a) For a review of disilene structural parameters, see: Okazaki, R.; West, R. Adv. Organomet. Chem. 1996, 39, 231. The average Si=Si distance for carbon-substituted disilenes is 216 pm, while silicon-substituted disilenes are typically 10 pm longer.
10. (b) Previously reported trans-bent pyramidalization angles fall in the range of 0°-18°, where the pyramidalization angle is defined as the angle of intersection between the Si=Si vertex and the plane made up of the silicon atom and its two substituents.
11. (c) By comparison, all of the other known disilenes have torsion angles between 0° and 14°.
12. Leites, L. A.; Bukalov, S. S.; Garbuzova, I. A.; West, R.; Mangette, J.; Spitzner, H. J. Organomet. Chem. 1997, 536-537, 425.
13. 2 show that an alternative mechanism for the formation of 7, involving intermediate formation of 2a followed by a 1,2 migration of an amino group, is energetically improbable.
14. 6, δ) -24.77, -34.41.
15. (a) All calculations were performed with Gaussian 94, Revision C.2-E2, Gaussian, Inc., Pittsburgh, PA, 1995.
16. (b) Parr, R. G.; Yang, W. Density-Functional Theory of Atoms and Molecules; Oxford University Press: New York, 1989.
17. (c) Lee, C.; Yang, W.; Parr, R. G. Phys. Rev. B 1988, 37, 785.
18. (d) Becke, A. D. J. Chem. Phys. 1993, 98, 5648
19. -1 higher in energy than two separated silylenes 1a.
20. 2N)Si is 11.3 kcal/mol (B3LYP/6-31G*). Thus, we estimate the entropy contribution for the dissociation 7 → 1a to be ca. 23 kcal/mol, in qualitative agreement with the observation that, in solution, 7 is in equilibrium with 1a.
21. Apeloig, Y.; Karni, M. J. Am. Chem. Soc. 1990, 112, 8589.
22. Trinquier, G.; Malrieu, J.-P. J. Am. Chem. Soc. 1991, 113, 8634.
23. 2): Si=Si, 233.4 pm; pyramidal angles at silicon, 47.4°; angle between the SiHN planes, 26.2° (B3LYP/6-311G**).