Carbene Analogues of Boron Stabilized by Neighboring B-B Moieties: Doubly Aromatic Bishomotriboriranides

Angewandte Chemie (International Edition in English)

Volumn 36, Issue 13-14, 1997, Pages 1469-1472

  Unverzagt, Markus ^a   Subramanian, Govindan ^b   Hofmann, Matthias ^b   Von Ragué Schleyer, Paul ^b   Berger, Stefan ^a   Harms, Klaus ^a   Massa, Werner ^a   Berndt, Armin ^a  

^a PHILIPPS UNIVERSITY MARBURG   (Germany)

^b UNIVERSITY OF ERLANGEN NUREMBERG   (Germany)

Author keywords

Ab initio calculations; Aromaticity; Boron; Carbenes

Indexed keywords

EID: 0030767354     PISSN: 05700833     EISSN: None     Source Type: Journal    
DOI: 10.1002/anie.199714691     Document Type: Article

References (32)

1. A. J. Arduengo III, R. L. Harlow, M. Kline, J. Am. Chem. Soc. 1991, 113, 361; A. J. Arduengo III, J. R. Goerlich, W. J. Marshall, ibid. 1995, 117, 11027, and references therein; R. W. Alder, P. R. Allen, M. Murray, A. G. Orpen, Angew. Chem. 1996, 108, 1211; Angew. Chem. Int. Ed. Engl. 1996, 35, 1121; recent review: M. Regitz, ibid. 1996, 108, 791 and 1996, 35, 725.
2. A. J. Arduengo III, R. L. Harlow, M. Kline, J. Am. Chem. Soc. 1991, 113, 361; A. J. Arduengo III, J. R. Goerlich, W. J. Marshall, ibid. 1995, 117, 11027, and references therein; R. W. Alder, P. R. Allen, M. Murray, A. G. Orpen, Angew. Chem. 1996, 108, 1211; Angew. Chem. Int. Ed. Engl. 1996, 35, 1121; recent review: M. Regitz, ibid. 1996, 108, 791 and 1996, 35, 725.
3. A. J. Arduengo III, R. L. Harlow, M. Kline, J. Am. Chem. Soc. 1991, 113, 361; A. J. Arduengo III, J. R. Goerlich, W. J. Marshall, ibid. 1995, 117, 11027, and references therein; R. W. Alder, P. R. Allen, M. Murray, A. G. Orpen, Angew. Chem. 1996, 108, 1211; Angew. Chem. Int. Ed. Engl. 1996, 35, 1121; recent review: M. Regitz, ibid. 1996, 108, 791 and 1996, 35, 725.
4. A. J. Arduengo III, R. L. Harlow, M. Kline, J. Am. Chem. Soc. 1991, 113, 361; A. J. Arduengo III, J. R. Goerlich, W. J. Marshall, ibid. 1995, 117, 11027, and references therein; R. W. Alder, P. R. Allen, M. Murray, A. G. Orpen, Angew. Chem. 1996, 108, 1211; Angew. Chem. Int. Ed. Engl. 1996, 35, 1121; recent review: M. Regitz, ibid. 1996, 108, 791 and 1996, 35, 725.
5. A. J. Arduengo III, R. L. Harlow, M. Kline, J. Am. Chem. Soc. 1991, 113, 361; A. J. Arduengo III, J. R. Goerlich, W. J. Marshall, ibid. 1995, 117, 11027, and references therein; R. W. Alder, P. R. Allen, M. Murray, A. G. Orpen, Angew. Chem. 1996, 108, 1211; Angew. Chem. Int. Ed. Engl. 1996, 35, 1121; recent review: M. Regitz, ibid. 1996, 108, 791 and 1996, 35, 725.
6. A. J. Arduengo III, R. L. Harlow, M. Kline, J. Am. Chem. Soc. 1991, 113, 361; A. J. Arduengo III, J. R. Goerlich, W. J. Marshall, ibid. 1995, 117, 11027, and references therein; R. W. Alder, P. R. Allen, M. Murray, A. G. Orpen, Angew. Chem. 1996, 108, 1211; Angew. Chem. Int. Ed. Engl. 1996, 35, 1121; recent review: M. Regitz, ibid. 1996, 108, 791 and 1996, 35, 725.
7. G. Boche, P. Andrews, K. Harms, M. Marsch, K. S. Rangappa, M. Schimeczek, C. Willeke, J. Am. Chem. Soc. 1996, 114, 4925.
8. -.
9. - described here is the simplest borylborenate.
10. a) E. Kaufmann, P. von R. Schleyer, Inorg. Chem. 1988, 27, 3987;
11. b) M. Wagner, N. J. R. van E. Hommes, H. Nöth, P. von R. Schleyer, ibid. 1995, 34, 607.
12. P. von R. Schleyer, H. Jiao, M. N. Glukhovtsev, J. Chandrasekhar, E. Kraka, J. Am. Chem. Soc. 1994, 116, 10129; J. Chandrasekhar, E. D. Jemmis, P. von R. Schleyer, Tetrahedron Lett. 1979, 3707.
13. P. von R. Schleyer, H. Jiao, M. N. Glukhovtsev, J. Chandrasekhar, E. Kraka, J. Am. Chem. Soc. 1994, 116, 10129; J. Chandrasekhar, E. D. Jemmis, P. von R. Schleyer, Tetrahedron Lett. 1979, 3707.
14. A. E. Reed, F. Weinhold, Chem. Rev. 1988, 88, 899.
15. A. Berndt, Angew. Chem. 1993, 105, 1034; Angew. Chem. Int. Ed. Engl. 1993, 32, 985.
16. A. Berndt, Angew. Chem. 1993, 105, 1034; Angew. Chem. Int. Ed. Engl. 1993, 32, 985.
17. Geometry of 5: see ref. [4].
18. A. Berndt, D. Steiner, D. Schweikart, C. Balzereit, M. Menzel, H.-J. Winkler, S. Mehle, M. Unverzagt, T. Happel, P. von R. Schleyer, G. Subramanian, M. Hofmann in Advances in Boron Chemistry (Ed.: W. Siebert), The Royal Society of Chemistry, Cambridge, 1997, p. 61.
19. In contrast to nitrogen atoms, which act as π donors and σ acceptors in amino substituants of persistent derivatives of 1 and 2, the B-B units in 4-7 act as π acceptors and σ donors.
20. MP2(FU)/6-31G*geometries computed with Gaussian 94: M. J. Frisch, G. W. Trucks, H. B. Schlegel, P. M. W. Gill, B. G. Johnson, M. A. Robb, J. R. Cheeseman, T. Keith, J. A. Petersson, J. A. Montgomery, K. Raghavachari, M. A. Al-Laham, V. G. Zakrzewski, J. Y. Ortiz, J. B. Foresman, J. Cioslowski, B. B. Stefanov, A. Nanayakkara, M. Challcombe, C. Y. Peng, P. Y. Ayala, W. Chen, M. W. Wong, J. L. Andres, E. S. Replogle, R. Gomperts, R. L. Martin, D. J. Fox, J. S. Blinkley, D. J. DeFrees, J. Baker, J. J. P. Stewart, M. Head-Gordon, C. Gonzalez, J. A. Pople, Gaussian, Pittsburgh, PA. 1995.
21. -1: C. Heinemann, T. Müller, Y. Apeloig, H. Schwarz, J. Am. Chem. Soc. 1996, 118, 2023.
22. M. Unverzagt, H.-J. Winkler, M. Brock, M. Hofmann, P. von R. Schleyer, W. Massa, A. Berndt, Angew. Chem. 1997, 109, 879; Angew. Chem. Int. Ed. Engl. 1997, 36, 853.
23. M. Unverzagt, H.-J. Winkler, M. Brock, M. Hofmann, P. von R. Schleyer, W. Massa, A. Berndt, Angew. Chem. 1997, 109, 879; Angew. Chem. Int. Ed. Engl. 1997, 36, 853.
24. The cis configuration of 10a unambiguously follows from the diastereotopy of the o- and m-carbon atoms and the attached methyl groups. This cannot be due to the different duryl groups, because only one signal each is seen for the i- and the p-carbon atoms.
25. Distances in 10c [pm]: B-B 176.1(4), BB-C 157.5(4), 158.0(4), ClB-C 155.2(3), 155.3(4), B-Cl 178.7(4), B⋯B (transannular) 238.0(6), 246.4(6).
26. GIAO-MP2: a) J. Gauss, Chem. Phys. Lett. 1992, 191, 614; b) J. Chem. Phys. 1993, 99, 3629. The method was implemented in ACESII (an ab initio program system: J. F. Stanton, J. Gauss, J. D. Watts, W. J. Lauderdale, R. J. Bartlett, Quantum Theory Project, University of Florida, Fl, 1991, 1992). The abbreviation tzp stands for triple zeta plus polarization basis set: A. Schäfer, H. Horn, R. Ahlrichs, J. Chem. Phys. 1992, 97, 2571.
27. GIAO-MP2: a) J. Gauss, Chem. Phys. Lett. 1992, 191, 614; b) J. Chem. Phys. 1993, 99, 3629. The method was implemented in ACESII (an ab initio program system: J. F. Stanton, J. Gauss, J. D. Watts, W. J. Lauderdale, R. J. Bartlett, Quantum Theory Project, University of Florida, Fl, 1991, 1992). The abbreviation tzp stands for triple zeta plus polarization basis set: A. Schäfer, H. Horn, R. Ahlrichs, J. Chem. Phys. 1992, 97, 2571.
28. GIAO-MP2: a) J. Gauss, Chem. Phys. Lett. 1992, 191, 614; b) J. Chem. Phys. 1993, 99, 3629. The method was implemented in ACESII (an ab initio program system: J. F. Stanton, J. Gauss, J. D. Watts, W. J. Lauderdale, R. J. Bartlett, Quantum Theory Project, University of Florida, Fl, 1991, 1992). The abbreviation tzp stands for triple zeta plus polarization basis set: A. Schäfer, H. Horn, R. Ahlrichs, J. Chem. Phys. 1992, 97, 2571.
29. GIAO-MP2: a) J. Gauss, Chem. Phys. Lett. 1992, 191, 614; b) J. Chem. Phys. 1993, 99, 3629. The method was implemented in ACESII (an ab initio program system: J. F. Stanton, J. Gauss, J. D. Watts, W. J. Lauderdale, R. J. Bartlett, Quantum Theory Project, University of Florida, Fl, 1991, 1992). The abbreviation tzp stands for triple zeta plus polarization basis set: A. Schäfer, H. Horn, R. Ahlrichs, J. Chem. Phys. 1992, 97, 2571.
30. GIAO-SCF/6-31G gives 20.8 (2B), 22.2 (1B), and -19.6 (C) for 7u and 94.1 (2B), 73.0 (IB), and 34.5 (C) for 10d.
31. -3. A Flack Parameter x = - 0.07(8) proves that the correct enantiomer has been refined. Crystallographic data (excluding structure factors) for the structures reported in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication no. CCDC-100161. Copies of the data can be obtained free of charge on application to The Director, CCDC, 12 Union Road, Cambridge CB21EZ, UK (fax: int. code + (1223) 336-033; e-mail : deposit@chemcrys.cam.ac.uk).
32. Compare for example the distances in Scheme 4 and the Wiberg bond indices: B1-B2 0.789, B2-B3 1.000, B1-C1 0.945, B2-C1 0.829, B2-H 0.946.