Synthesis of Boryl Metal Complexes with Additional Agostic Stabilization by Hydroboration of Fischer Carbyne Complexes

Angewandte Chemie (International Edition in English)

Volumn 36, Issue 9, 1997, Pages 974-976

  Wadepohl, Hubert ^a   Arnold, Ulrich ^a   Pritzkow, Hans ^a  

^a UNIVERSITY OF HEIDELBERG   (Germany)

Author keywords

Agostic interactions; Boron; Carbyne complexes; Hydroboration

Indexed keywords

EID: 0030970696     PISSN: 05700833     EISSN: None     Source Type: Journal    
DOI: 10.1002/anie.199709741     Document Type: Article

References (51)

1. G. Schmid, Angew. Chem. 1970, 82, 920; Angew. Chem. Int. Ed. Engl. 1970, 9, 819, and references therein.
2. G. Schmid, Angew. Chem. 1970, 82, 920; Angew. Chem. Int. Ed. Engl. 1970, 9, 819, and references therein.
3. a) C. S. Cundy, H. Nöth, J. Organomet. Chem. 1971, 30, 135;
4. b) H. Kono, K. Ito, Y. Nagai, Chem. Lett. 1975, 1095;
5. c) M. Fishwick, H. Nöth, W. Petz, M. G. H. Wallbridge, Inorg. Chem. 1976, 15, 490.
6. J. R. Knorr, J. S. Merola, Organometallics 1990, 9, 3008.
7. a) R. T. Baker, D. W. Ovenall, J. C. Calabrese, S. A. Westcott, N. J. Taylor, I. D. Williams, T. B. Marder, J. Am. Chem. Soc. 1990, 112, 9399;
8. b) S. A. Westcott, N. J. Taylor, T. B. Marder, R. T. Baker, N J. Jones, J. C. Calabrese, J. Chem. Soc. Chem. Commun. 1991, 304;
9. c) S. A. Westcott, T. B. Marder, R. T. Baker, J. C. Calabrese, Can. J. Chem. 1993, 71, 930;
10. d) K. Burgess, W. A. van der Donk, S. A. Westcott, T. B. Marder, R. T. Baker, J. C. Calabrese, J. Am. Chem. Soc. 1992, 114, 9350:
11. e) R. T. Baker, J. C. Calabrese, S. A. Westcott, P. Nguyen, T. B. Marder, ibid. 1993, 115, 4367;
12. f) P. Nguyen, H. P. Blom, S. A. Westcott, N. J. Taylor, T. B. Marder, ibid. 1993, 115, 9329.
13. a) J. F. Hartwig, S. Huber, J. Am. Chem. Soc. 1993, 115, 4908;
14. b) J. F. Hartwig, S. Bhandari, P. R. Rablen, ibid. 1994, 116, 1839;
15. c) J. F. Hartwig, S. R. De Gala, ibid. 1994, 116, 3661;
16. d) P. R. Rablen, J. F Hartwig, S. P. Nolan, ibid. 1994, 116, 4121;
17. e) X. He, J. F. Hartwig, Organometallics 1996, 15, 400;
18. f) J. F. Hartwig, X. He, Angew. Chem. 1996, 108, 352; Angew. Chem. Int. Ed. Engl. 1996, 35, 315.
19. f) J. F. Hartwig, X. He, Angew. Chem. 1996, 108, 352; Angew. Chem. Int. Ed. Engl. 1996, 35, 315.
20. D. R. Lantero, D. H. Motry, D. L. Ward, M. R. Smith III, J. Am. Chem. Soc. 1994, 116, 10811.
21. C. N. Iverson, M. R. Smith III, J. Am. Chem. Soc. 1995, 117, 4403.
22. D. Männig, H. Nöth, Angew. Chem. 1985, 97, 854; Angew. Chem. Int. Ed. Engl. 1985, 24, 878. A more up-to-date overview: K. Burgess, M. J. Ohlmeyer, Chem. Rev. 1991, 91, 1179. Mechanism: A. E. Dorigo, P. von R. Schleyer, Angew. Chem. 1995, 107, 108; Angew. Chem. Int. Ed Engl. 1995, 34, 115.
23. D. Männig, H. Nöth, Angew. Chem. 1985, 97, 854; Angew. Chem. Int. Ed. Engl. 1985, 24, 878. A more up-to-date overview: K. Burgess, M. J. Ohlmeyer, Chem. Rev. 1991, 91, 1179. Mechanism: A. E. Dorigo, P. von R. Schleyer, Angew. Chem. 1995, 107, 108; Angew. Chem. Int. Ed Engl. 1995, 34, 115.
24. D. Männig, H. Nöth, Angew. Chem. 1985, 97, 854; Angew. Chem. Int. Ed. Engl. 1985, 24, 878. A more up-to-date overview: K. Burgess, M. J. Ohlmeyer, Chem. Rev. 1991, 91, 1179. Mechanism: A. E. Dorigo, P. von R. Schleyer, Angew. Chem. 1995, 107, 108; Angew. Chem. Int. Ed Engl. 1995, 34, 115.
25. D. Männig, H. Nöth, Angew. Chem. 1985, 97, 854; Angew. Chem. Int. Ed. Engl. 1985, 24, 878. A more up-to-date overview: K. Burgess, M. J. Ohlmeyer, Chem. Rev. 1991, 91, 1179. Mechanism: A. E. Dorigo, P. von R. Schleyer, Angew. Chem. 1995, 107, 108; Angew. Chem. Int. Ed Engl. 1995, 34, 115.
26. D. Männig, H. Nöth, Angew. Chem. 1985, 97, 854; Angew. Chem. Int. Ed. Engl. 1985, 24, 878. A more up-to-date overview: K. Burgess, M. J. Ohlmeyer, Chem. Rev. 1991, 91, 1179. Mechanism: A. E. Dorigo, P. von R. Schleyer, Angew. Chem. 1995, 107, 108; Angew. Chem. Int. Ed Engl. 1995, 34, 115.
27. G. Schmid, H. Nöth, Chem. Ber. 1967, 100, 2899.
28. a) H. Wadepohl, G. P. Elliot, H. Pritzkow, F. G. A. Stone, A. Wolf, J. Organomet. Chem. 1994, 482, 243;
29. b) U. Arnold, Diploma thesis, Universität Heidelberg, 1995;
30. c) H. Wadepohl, U. Arnold, H. Pritzkow, A. Wolf, in Advances in Boron Chemistry (Ed.: W. Siebert), The Royal Society of Chemistry, London, in press.
31. 6-n, tetraethyldiborane-6 is an equilibrium mixture of diboranes differing in their number of alkyl substituents, since the exchange of alkyl groups between the boron atoms is catalyzed by the BH functional groups: R. Köster, G. Bruno, P. Binger, Justus Liebigs Ann. Chem. 1961, 644, 1.
32. 6-n, tetraethyldiborane-6 is an equilibrium mixture of diboranes differing in their number of alkyl substituents, since the exchange of alkyl groups between the boron atoms is catalyzed by the BH functional groups: R. Köster, G. Bruno, P. Binger, Justus Liebigs Ann. Chem. 1961, 644, 1.
33. "Nuclear Magnetic Resonance Spectroscopy of Boron Compounds": H. Nöth, B. Wrackmeyer, NMR Basic Princ. Prog. 1978, 14, Chap. 4.
34. The extremely air-sensitive single crystals that are obtained by slow cooling of the reaction mixture contain one (disordered) toluene molecule and half a molecule of tetraethylborane-6 per assymmetric unit [d(B-C) = 1.58(2), 1.62(2) Å; d(B-B) = 1.82(4) Å, C-B-C angle 120(1)°].
35. c)/3, GooF = 1.025. Crystallographic data (excluding structure factors) for the structure reported in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication no. CCDC-100 156. Copies of the data can be obtained free of charge on application to The Director, CCDC, 12 Union Road, Cambridge CB2 1EZ, UK (fax: Int. code +(1223) 336-033; e-mail: deposit@chemcrys.cam.ac.uk).
36. a) SHELXS-86: G. M. Sheldrick, Acta Crystallogr. Sect. A 1990, 46, 467;
37. b) SHELXL-93: G. M. Sheldrick, Universität Göttigen, 1993.
38. The Cambridge Crystallographic Database contains W-B bond lengths between 2.170 and 2.557 Å.
39. H. Braunschweig, B. Ganter, M. Koster, T. Wagner, Chem. Ber. 1996, 129, 1099.
40. 1J(C,H(agostic)) becomes smaller[19]; this has been experimentally verified for the carbene complexes 7[20). The obvious comparison with the signal of the methylene group of the nonagostic ethyl group in 6 is not possible due to overlap with the methyl signals.
41. M. Brookhart, M. L. H. Green, J. Organomet. Chem. 1983, 250, 395.
42. S. G. Feng, P. S. White, J. L. Templeton, J. Am. Chem. Soc. 1990, 112, 8192; ibid. 1992, 114, 2951.
43. S. G. Feng, P. S. White, J. L. Templeton, J. Am. Chem. Soc. 1990, 112, 8192; ibid. 1992, 114, 2951.
44. J. Emsley, The Elements, 2nd ed., Clarendon, Oxford, 1991.
45. N. M. Kostic, R. F. Fenske, Organometallics 1982, 1, 974.
46. M. D. Curtis, K.-B. Shiu, W. M. Butler, J. C. Huffman, J. Am. Chem. Soc. 1986, 108, 3335.
47. 2-p-tolyl] under milder conditions (room temperature) and faster (<5 min) would tend to indicate that this is not the case here.
48. R. J. Kazlauskas, M. S. Wrighton, J. Am. Chem. Soc. 1982, 104, 6005.
49. 5)] leads via several intermediates to 10[25]. We observed magnetization transfer between the hydridic and olefinic protons in 10 [10 b] by NMR spectroscopy. This can be explained by a dynamic equilibrium between 10 and 11.
50. J. C. Jefferey, F. G. A. Stone, G. K. Williams, Polyhedron 1991, 10, 215.
51. R. Köster, P. Binger, Inorg. Synth. 1974, 15, 142.