First structurally authenticated heavier alkali metal phosphinomethanide

Organometallics

Volumn 18, Issue 16, 1999, Pages 2939-2940

  Clegg, William ^a   Izod, Keith ^a   O'Shaughnessy, Paul ^a  

^a NEWCASTLE UNIVERSITY   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001173273     PISSN: 02767333     EISSN: None     Source Type: Journal    
DOI: 10.1021/om990276j     Document Type: Article

References (34)

1. For examples see: (a) Karsch, H. H. Russ. Chem. Bull. 1993, 42, 1937. (b) Karsch, H. H.; Zellner, K.; Mikulcik, P.; Laehmann, J.; Muller, G. Organometallics 1990, 9, 190. (c) Karsch, H. H.; Deubelly, B.; Hofmann, J.; Pieper, U.; Muller, G. J. Am. Chem. Soc. 1988, 110, 3654. (d) Karsch, H. H.; Grauvogl, G.; Mikulcik, P.; Bissinger, P.; Muller, G. J. Organomet. Chem. 1994, 465, 65. (e) Karsch, H. H.; Perazin, G.; Bissinger, P. Chem. Commun. 1994, 505. (f) Clegg, W.; Izod, K.; McFarlane, W.; O'Shaughnessy, P. Organometallics 1998, 17, 5231. (g) Denmark, S. E.; Swiss, K. A.; Wilson, S. R. Angew. Chem., Int. Ed. Engl. 1996, 35, 2515. (h) Cramer, C. J.; Denmark, S. E.; Miller, P. C.; Dorow, R. L.; Swiss, K. A.; Wilson, S. R. J. Am. Chem. Soc. 1994, 116, 2437.
2. For examples see: (a) Karsch, H. H. Russ. Chem. Bull. 1993, 42, 1937. (b) Karsch, H. H.; Zellner, K.; Mikulcik, P.; Laehmann, J.; Muller, G. Organometallics 1990, 9, 190. (c) Karsch, H. H.; Deubelly, B.; Hofmann, J.; Pieper, U.; Muller, G. J. Am. Chem. Soc. 1988, 110, 3654. (d) Karsch, H. H.; Grauvogl, G.; Mikulcik, P.; Bissinger, P.; Muller, G. J. Organomet. Chem. 1994, 465, 65. (e) Karsch, H. H.; Perazin, G.; Bissinger, P. Chem. Commun. 1994, 505. (f) Clegg, W.; Izod, K.; McFarlane, W.; O'Shaughnessy, P. Organometallics 1998, 17, 5231. (g) Denmark, S. E.; Swiss, K. A.; Wilson, S. R. Angew. Chem., Int. Ed. Engl. 1996, 35, 2515. (h) Cramer, C. J.; Denmark, S. E.; Miller, P. C.; Dorow, R. L.; Swiss, K. A.; Wilson, S. R. J. Am. Chem. Soc. 1994, 116, 2437.
3. For examples see: (a) Karsch, H. H. Russ. Chem. Bull. 1993, 42, 1937. (b) Karsch, H. H.; Zellner, K.; Mikulcik, P.; Laehmann, J.; Muller, G. Organometallics 1990, 9, 190. (c) Karsch, H. H.; Deubelly, B.; Hofmann, J.; Pieper, U.; Muller, G. J. Am. Chem. Soc. 1988, 110, 3654. (d) Karsch, H. H.; Grauvogl, G.; Mikulcik, P.; Bissinger, P.; Muller, G. J. Organomet. Chem. 1994, 465, 65. (e) Karsch, H. H.; Perazin, G.; Bissinger, P. Chem. Commun. 1994, 505. (f) Clegg, W.; Izod, K.; McFarlane, W.; O'Shaughnessy, P. Organometallics 1998, 17, 5231. (g) Denmark, S. E.; Swiss, K. A.; Wilson, S. R. Angew. Chem., Int. Ed. Engl. 1996, 35, 2515. (h) Cramer, C. J.; Denmark, S. E.; Miller, P. C.; Dorow, R. L.; Swiss, K. A.; Wilson, S. R. J. Am. Chem. Soc. 1994, 116, 2437.
4. For examples see: (a) Karsch, H. H. Russ. Chem. Bull. 1993, 42, 1937. (b) Karsch, H. H.; Zellner, K.; Mikulcik, P.; Laehmann, J.; Muller, G. Organometallics 1990, 9, 190. (c) Karsch, H. H.; Deubelly, B.; Hofmann, J.; Pieper, U.; Muller, G. J. Am. Chem. Soc. 1988, 110, 3654. (d) Karsch, H. H.; Grauvogl, G.; Mikulcik, P.; Bissinger, P.; Muller, G. J. Organomet. Chem. 1994, 465, 65. (e) Karsch, H. H.; Perazin, G.; Bissinger, P. Chem. Commun. 1994, 505. (f) Clegg, W.; Izod, K.; McFarlane, W.; O'Shaughnessy, P. Organometallics 1998, 17, 5231. (g) Denmark, S. E.; Swiss, K. A.; Wilson, S. R. Angew. Chem., Int. Ed. Engl. 1996, 35, 2515. (h) Cramer, C. J.; Denmark, S. E.; Miller, P. C.; Dorow, R. L.; Swiss, K. A.; Wilson, S. R. J. Am. Chem. Soc. 1994, 116, 2437.
5. For examples see: (a) Karsch, H. H. Russ. Chem. Bull. 1993, 42, 1937. (b) Karsch, H. H.; Zellner, K.; Mikulcik, P.; Laehmann, J.; Muller, G. Organometallics 1990, 9, 190. (c) Karsch, H. H.; Deubelly, B.; Hofmann, J.; Pieper, U.; Muller, G. J. Am. Chem. Soc. 1988, 110, 3654. (d) Karsch, H. H.; Grauvogl, G.; Mikulcik, P.; Bissinger, P.; Muller, G. J. Organomet. Chem. 1994, 465, 65. (e) Karsch, H. H.; Perazin, G.; Bissinger, P. Chem. Commun. 1994, 505. (f) Clegg, W.; Izod, K.; McFarlane, W.; O'Shaughnessy, P. Organometallics 1998, 17, 5231. (g) Denmark, S. E.; Swiss, K. A.; Wilson, S. R. Angew. Chem., Int. Ed. Engl. 1996, 35, 2515. (h) Cramer, C. J.; Denmark, S. E.; Miller, P. C.; Dorow, R. L.; Swiss, K. A.; Wilson, S. R. J. Am. Chem. Soc. 1994, 116, 2437.
6. For examples see: (a) Karsch, H. H. Russ. Chem. Bull. 1993, 42, 1937. (b) Karsch, H. H.; Zellner, K.; Mikulcik, P.; Laehmann, J.; Muller, G. Organometallics 1990, 9, 190. (c) Karsch, H. H.; Deubelly, B.; Hofmann, J.; Pieper, U.; Muller, G. J. Am. Chem. Soc. 1988, 110, 3654. (d) Karsch, H. H.; Grauvogl, G.; Mikulcik, P.; Bissinger, P.; Muller, G. J. Organomet. Chem. 1994, 465, 65. (e) Karsch, H. H.; Perazin, G.; Bissinger, P. Chem. Commun. 1994, 505. (f) Clegg, W.; Izod, K.; McFarlane, W.; O'Shaughnessy, P. Organometallics 1998, 17, 5231. (g) Denmark, S. E.; Swiss, K. A.; Wilson, S. R. Angew. Chem., Int. Ed. Engl. 1996, 35, 2515. (h) Cramer, C. J.; Denmark, S. E.; Miller, P. C.; Dorow, R. L.; Swiss, K. A.; Wilson, S. R. J. Am. Chem. Soc. 1994, 116, 2437.
7. For examples see: (a) Karsch, H. H. Russ. Chem. Bull. 1993, 42, 1937. (b) Karsch, H. H.; Zellner, K.; Mikulcik, P.; Laehmann, J.; Muller, G. Organometallics 1990, 9, 190. (c) Karsch, H. H.; Deubelly, B.; Hofmann, J.; Pieper, U.; Muller, G. J. Am. Chem. Soc. 1988, 110, 3654. (d) Karsch, H. H.; Grauvogl, G.; Mikulcik, P.; Bissinger, P.; Muller, G. J. Organomet. Chem. 1994, 465, 65. (e) Karsch, H. H.; Perazin, G.; Bissinger, P. Chem. Commun. 1994, 505. (f) Clegg, W.; Izod, K.; McFarlane, W.; O'Shaughnessy, P. Organometallics 1998, 17, 5231. (g) Denmark, S. E.; Swiss, K. A.; Wilson, S. R. Angew. Chem., Int. Ed. Engl. 1996, 35, 2515. (h) Cramer, C. J.; Denmark, S. E.; Miller, P. C.; Dorow, R. L.; Swiss, K. A.; Wilson, S. R. J. Am. Chem. Soc. 1994, 116, 2437.
8. For examples see: (a) Karsch, H. H. Russ. Chem. Bull. 1993, 42, 1937. (b) Karsch, H. H.; Zellner, K.; Mikulcik, P.; Laehmann, J.; Muller, G. Organometallics 1990, 9, 190. (c) Karsch, H. H.; Deubelly, B.; Hofmann, J.; Pieper, U.; Muller, G. J. Am. Chem. Soc. 1988, 110, 3654. (d) Karsch, H. H.; Grauvogl, G.; Mikulcik, P.; Bissinger, P.; Muller, G. J. Organomet. Chem. 1994, 465, 65. (e) Karsch, H. H.; Perazin, G.; Bissinger, P. Chem. Commun. 1994, 505. (f) Clegg, W.; Izod, K.; McFarlane, W.; O'Shaughnessy, P. Organometallics 1998, 17, 5231. (g) Denmark, S. E.; Swiss, K. A.; Wilson, S. R. Angew. Chem., Int. Ed. Engl. 1996, 35, 2515. (h) Cramer, C. J.; Denmark, S. E.; Miller, P. C.; Dorow, R. L.; Swiss, K. A.; Wilson, S. R. J. Am. Chem. Soc. 1994, 116, 2437.
9. For recent reviews of alkali metal Organometallics see: (a) Schade, C.; Schleyer, P. v. R. Adv. Organomet. Chem. 1987, 27, 169. (b) Willard, P. G. In Comprehensive Organic Synthesis, Vol. 1; Trost, B. M., Fleming, I., Eds.; Pergammon Press: New York, 1991; pp 1-47. (c) Setzer, W. N.; Schleyer, P. v. R. Adv. Organomet. Chem. 1985, 24, 353. (d) Weiss, E. Angew. Chem., Int. Ed. Engl. 1993, 11, 1501. (e) Smith, J. D. Adv. Organomet. Chem. 1998, 43, 267.
10. For recent reviews of alkali metal Organometallics see: (a) Schade, C.; Schleyer, P. v. R. Adv. Organomet. Chem. 1987, 27, 169. (b) Willard, P. G. In Comprehensive Organic Synthesis, Vol. 1; Trost, B. M., Fleming, I., Eds.; Pergammon Press: New York, 1991; pp 1-47. (c) Setzer, W. N.; Schleyer, P. v. R. Adv. Organomet. Chem. 1985, 24, 353. (d) Weiss, E. Angew. Chem., Int. Ed. Engl. 1993, 11, 1501. (e) Smith, J. D. Adv. Organomet. Chem. 1998, 43, 267.
11. For recent reviews of alkali metal Organometallics see: (a) Schade, C.; Schleyer, P. v. R. Adv. Organomet. Chem. 1987, 27, 169. (b) Willard, P. G. In Comprehensive Organic Synthesis, Vol. 1; Trost, B. M., Fleming, I., Eds.; Pergammon Press: New York, 1991; pp 1-47. (c) Setzer, W. N.; Schleyer, P. v. R. Adv. Organomet. Chem. 1985, 24, 353. (d) Weiss, E. Angew. Chem., Int. Ed. Engl. 1993, 11, 1501. (e) Smith, J. D. Adv. Organomet. Chem. 1998, 43, 267.
12. For recent reviews of alkali metal Organometallics see: (a) Schade, C.; Schleyer, P. v. R. Adv. Organomet. Chem. 1987, 27, 169. (b) Willard, P. G. In Comprehensive Organic Synthesis, Vol. 1; Trost, B. M., Fleming, I., Eds.; Pergammon Press: New York, 1991; pp 1-47. (c) Setzer, W. N.; Schleyer, P. v. R. Adv. Organomet. Chem. 1985, 24, 353. (d) Weiss, E. Angew. Chem., Int. Ed. Engl. 1993, 11, 1501. (e) Smith, J. D. Adv. Organomet. Chem. 1998, 43, 267.
13. For recent reviews of alkali metal Organometallics see: (a) Schade, C.; Schleyer, P. v. R. Adv. Organomet. Chem. 1987, 27, 169. (b) Willard, P. G. In Comprehensive Organic Synthesis, Vol. 1; Trost, B. M., Fleming, I., Eds.; Pergammon Press: New York, 1991; pp 1-47. (c) Setzer, W. N.; Schleyer, P. v. R. Adv. Organomet. Chem. 1985, 24, 353. (d) Weiss, E. Angew. Chem., Int. Ed. Engl. 1993, 11, 1501. (e) Smith, J. D. Adv. Organomet. Chem. 1998, 43, 267.
14. (a) Hiller, W. G.; Layh, M.; Uhl, W. Angew. Chem., Int. Ed. Engl. 1991, 30, 324.
15. (b) Eaborn, C.; Izod, K.; Smith, J. D. J. Organomet. Chem. 1995, 500, 89, and references therein.
16. (c) Eaborn, C.; Clegg, W.; Hitchcock, P. B.; Hopman, M.; Izod, K.; O'Shaughnessy, P. N.; Smith, J. D. Organometallics 1997, 16, 4728
17. (d) Hitchcock, P. B.; Lappert, M. F.; Leung, W.-P.; Diansheng, L.; Shun, T. Chem. Commun. 1993, 1386.
18. A potassium phosphinomethanide has been reported as an intermediate in the synthesis of a lanthanide phosphinomethanide complex but was not isolated. Karseh, H. H.; Appelt, A.; Müller, G. Angew. Chem., Int. Ed. Engl. 1986, 25, 823.
19. Clegg, W.; Doherty, S.; Izod, K.; O'Shaughnessy, P. Chem. Commun. 1998, 1129.
20. 8, 297 K): δ -7.9.
21. -3.
22. For leading references to potassium phosphide complexes see: (a) Frenzel, C.; Jörchel, P.; Hey-Hawkins, E. Chem. Commun. 1998, 1363. (b) Englich, U.; Hassler, K.; Ruhlandt-Senge, M.; Uhlig, F. Inorg. Chem. 1998, 37, 3532. (c) Fermin, M.; Ho, J.; Stephan, D. W. Organometallics 1995, 14, 4247. (d) Beswick, M. A.; Hopkins, A. D.; Kerr, L. C.; Mosquera, M. E. G.; Palmer, J. S.; Raithby, P. R.; Rothenberger, A.; Stalke, D.; Wheatley, A. E. H.; Wright, D. S. Chem. Commun. 1998, 1527. (e) Andrianarison, M.; Stalke, D.; Klingebiel, U. Chem. Ber. 1990, 123, 71. (f) Rabe, G. W.; Yap, G. P. A.; Rheingold, A. L. Inorg. Chem. 1997, 36, 1990.
23. For leading references to potassium phosphide complexes see: (a) Frenzel, C.; Jörchel, P.; Hey-Hawkins, E. Chem. Commun. 1998, 1363. (b) Englich, U.; Hassler, K.; Ruhlandt-Senge, M.; Uhlig, F. Inorg. Chem. 1998, 37, 3532. (c) Fermin, M.; Ho, J.; Stephan, D. W. Organometallics 1995, 14, 4247. (d) Beswick, M. A.; Hopkins, A. D.; Kerr, L. C.; Mosquera, M. E. G.; Palmer, J. S.; Raithby, P. R.; Rothenberger, A.; Stalke, D.; Wheatley, A. E. H.; Wright, D. S. Chem. Commun. 1998, 1527. (e) Andrianarison, M.; Stalke, D.; Klingebiel, U. Chem. Ber. 1990, 123, 71. (f) Rabe, G. W.; Yap, G. P. A.; Rheingold, A. L. Inorg. Chem. 1997, 36, 1990.
24. For leading references to potassium phosphide complexes see: (a) Frenzel, C.; Jörchel, P.; Hey-Hawkins, E. Chem. Commun. 1998, 1363. (b) Englich, U.; Hassler, K.; Ruhlandt-Senge, M.; Uhlig, F. Inorg. Chem. 1998, 37, 3532. (c) Fermin, M.; Ho, J.; Stephan, D. W. Organometallics 1995, 14, 4247. (d) Beswick, M. A.; Hopkins, A. D.; Kerr, L. C.; Mosquera, M. E. G.; Palmer, J. S.; Raithby, P. R.; Rothenberger, A.; Stalke, D.; Wheatley, A. E. H.; Wright, D. S. Chem. Commun. 1998, 1527. (e) Andrianarison, M.; Stalke, D.; Klingebiel, U. Chem. Ber. 1990, 123, 71. (f) Rabe, G. W.; Yap, G. P. A.; Rheingold, A. L. Inorg. Chem. 1997, 36, 1990.
25. For leading references to potassium phosphide complexes see: (a) Frenzel, C.; Jörchel, P.; Hey-Hawkins, E. Chem. Commun. 1998, 1363. (b) Englich, U.; Hassler, K.; Ruhlandt-Senge, M.; Uhlig, F. Inorg. Chem. 1998, 37, 3532. (c) Fermin, M.; Ho, J.; Stephan, D. W. Organometallics 1995, 14, 4247. (d) Beswick, M. A.; Hopkins, A. D.; Kerr, L. C.; Mosquera, M. E. G.; Palmer, J. S.; Raithby, P. R.; Rothenberger, A.; Stalke, D.; Wheatley, A. E. H.; Wright, D. S. Chem. Commun. 1998, 1527. (e) Andrianarison, M.; Stalke, D.; Klingebiel, U. Chem. Ber. 1990, 123, 71. (f) Rabe, G. W.; Yap, G. P. A.; Rheingold, A. L. Inorg. Chem. 1997, 36, 1990.
26. For leading references to potassium phosphide complexes see: (a) Frenzel, C.; Jörchel, P.; Hey-Hawkins, E. Chem. Commun. 1998, 1363. (b) Englich, U.; Hassler, K.; Ruhlandt-Senge, M.; Uhlig, F. Inorg. Chem. 1998, 37, 3532. (c) Fermin, M.; Ho, J.; Stephan, D. W. Organometallics 1995, 14, 4247. (d) Beswick, M. A.; Hopkins, A. D.; Kerr, L. C.; Mosquera, M. E. G.; Palmer, J. S.; Raithby, P. R.; Rothenberger, A.; Stalke, D.; Wheatley, A. E. H.; Wright, D. S. Chem. Commun. 1998, 1527. (e) Andrianarison, M.; Stalke, D.; Klingebiel, U. Chem. Ber. 1990, 123, 71. (f) Rabe, G. W.; Yap, G. P. A.; Rheingold, A. L. Inorg. Chem. 1997, 36, 1990.
27. For leading references to potassium phosphide complexes see: (a) Frenzel, C.; Jörchel, P.; Hey-Hawkins, E. Chem. Commun. 1998, 1363. (b) Englich, U.; Hassler, K.; Ruhlandt-Senge, M.; Uhlig, F. Inorg. Chem. 1998, 37, 3532. (c) Fermin, M.; Ho, J.; Stephan, D. W. Organometallics 1995, 14, 4247. (d) Beswick, M. A.; Hopkins, A. D.; Kerr, L. C.; Mosquera, M. E. G.; Palmer, J. S.; Raithby, P. R.; Rothenberger, A.; Stalke, D.; Wheatley, A. E. H.; Wright, D. S. Chem. Commun. 1998, 1527. (e) Andrianarison, M.; Stalke, D.; Klingebiel, U. Chem. Ber. 1990, 123, 71. (f) Rabe, G. W.; Yap, G. P. A.; Rheingold, A. L. Inorg. Chem. 1997, 36, 1990.
28. Complexes containing a Na-P(phosphine) contact have been reported previously, as have two complexes containing a K-P(phospholide) contact. Na-P(phosphine) contacts: (a) Fryzuk, M. D.; Gao, X.; Rettig, S. J. Can. J. Chem. 1995, 73, 1175. (b) Lin, G.; Wong, W.-T. Polyhedron 1994, 13, 3027. (c) Schmidbaur, H.; Deschler, U.; Zimmer-Gasser, B.; Neugebauer, D.; Schubert, U. Chem. Ber. 1980, 113, 902. K-P(phospholide) contacts (d) Paul, F.; Carmichael, D.; Ricard, L.; Mathey, F. Angew, Chem., Int. Ed. Engl. 1996, 108, 1204. (e) Gosink, H.-J.; Nief, F.; Ricard, L.; Mathey, F. Inorg. Chem. 1995, 34, 1306.
29. Complexes containing a Na-P(phosphine) contact have been reported previously, as have two complexes containing a K-P(phospholide) contact. Na-P(phosphine) contacts: (a) Fryzuk, M. D.; Gao, X.; Rettig, S. J. Can. J. Chem. 1995, 73, 1175. (b) Lin, G.; Wong, W.-T. Polyhedron 1994, 13, 3027. (c) Schmidbaur, H.; Deschler, U.; Zimmer-Gasser, B.; Neugebauer, D.; Schubert, U. Chem. Ber. 1980, 113, 902. K-P(phospholide) contacts (d) Paul, F.; Carmichael, D.; Ricard, L.; Mathey, F. Angew, Chem., Int. Ed. Engl. 1996, 108, 1204. (e) Gosink, H.-J.; Nief, F.; Ricard, L.; Mathey, F. Inorg. Chem. 1995, 34, 1306.
30. Complexes containing a Na-P(phosphine) contact have been reported previously, as have two complexes containing a K-P(phospholide) contact. Na-P(phosphine) contacts: (a) Fryzuk, M. D.; Gao, X.; Rettig, S. J. Can. J. Chem. 1995, 73, 1175. (b) Lin, G.; Wong, W.-T. Polyhedron 1994, 13, 3027. (c) Schmidbaur, H.; Deschler, U.; Zimmer-Gasser, B.; Neugebauer, D.; Schubert, U. Chem. Ber. 1980, 113, 902. K-P(phospholide) contacts (d) Paul, F.; Carmichael, D.; Ricard, L.; Mathey, F. Angew, Chem., Int. Ed. Engl. 1996, 108, 1204. (e) Gosink, H.-J.; Nief, F.; Ricard, L.; Mathey, F. Inorg. Chem. 1995, 34, 1306.
31. Complexes containing a Na-P(phosphine) contact have been reported previously, as have two complexes containing a K-P(phospholide) contact. Na-P(phosphine) contacts: (a) Fryzuk, M. D.; Gao, X.; Rettig, S. J. Can. J. Chem. 1995, 73, 1175. (b) Lin, G.; Wong, W.-T. Polyhedron 1994, 13, 3027. (c) Schmidbaur, H.; Deschler, U.; Zimmer-Gasser, B.; Neugebauer, D.; Schubert, U. Chem. Ber. 1980, 113, 902. K-P(phospholide) contacts (d) Paul, F.; Carmichael, D.; Ricard, L.; Mathey, F. Angew, Chem., Int. Ed. Engl. 1996, 108, 1204. (e) Gosink, H.-J.; Nief, F.; Ricard, L.; Mathey, F. Inorg. Chem. 1995, 34, 1306.
32. Complexes containing a Na-P(phosphine) contact have been reported previously, as have two complexes containing a K-P(phospholide) contact. Na-P(phosphine) contacts: (a) Fryzuk, M. D.; Gao, X.; Rettig, S. J. Can. J. Chem. 1995, 73, 1175. (b) Lin, G.; Wong, W.-T. Polyhedron 1994, 13, 3027. (c) Schmidbaur, H.; Deschler, U.; Zimmer-Gasser, B.; Neugebauer, D.; Schubert, U. Chem. Ber. 1980, 113, 902. K-P(phospholide) contacts (d) Paul, F.; Carmichael, D.; Ricard, L.; Mathey, F. Angew, Chem., Int. Ed. Engl. 1996, 108, 1204. (e) Gosink, H.-J.; Nief, F.; Ricard, L.; Mathey, F. Inorg. Chem. 1995, 34, 1306.
33. For examples see: (a) Eaborn, C.; Hitchcock, P. B.; Izod, K.; Smith, J. D. Angew. Chem., Int. Ed. Engl. 1995, 34, 2679. (b) Eaborn, C.; Hitchcock, P. B.; Izod, K.; Jaggar, A. J.; Smith, J. D. Organometallics 1994, 13, 753.
34. For examples see: (a) Eaborn, C.; Hitchcock, P. B.; Izod, K.; Smith, J. D. Angew. Chem., Int. Ed. Engl. 1995, 34, 2679. (b) Eaborn, C.; Hitchcock, P. B.; Izod, K.; Jaggar, A. J.; Smith, J. D. Organometallics 1994, 13, 753.