Catalytic isomerization and disproportionation of olefins promoted by group 4/d0 benzamidinate complexes

Journal of the American Chemical Society

Volumn 121, Issue 38, 1999, Pages 8755-8759

  Averbuj, Claudia ^a   Eisen, Moris S ^a  

^a TECHNION ISRAEL INSTITUTE OF TECHNOLOGY   (Israel)

Author keywords

[No Author keywords available]

Indexed keywords

ALKADIENE; ALKENE; BENZAMIDINE DERIVATIVE; BENZENE DERIVATIVE; HYDROGEN; METHANE; ZIRCONIUM DERIVATIVE;

ARTICLE; CARBON NUCLEAR MAGNETIC RESONANCE; CATALYSIS; COMPLEX FORMATION; ISOMERISM; PROTON NUCLEAR MAGNETIC RESONANCE;

EID: 0033615323     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja990011w     Document Type: Article

References (49)

1. For some group 3 and lanthanide complexes, see: (a) Edelmann, F. T.; Richter, J. Eur. J. Solid State Inorg. Chem. 1996, 33, 157. (b) Hagardon, J. R., Arnold, J. Organometallics 1996, 15, 984. (c) Edelmann, F. T. Top. Curr. Chem. 1996, 179, 113 and references therein, (d) Duchateau, R.; van Wee, C. T.; Meetsma, A.; van Duijnen, P. Th.; Teuben, J. H. Organometallics 1996, 15, 2279. (e) Duchateau, R.; van Wee, C. T.; Teuben, J. H. Organometallics 1996, 15, 2291. (f) Edelmann, F. T. Coord. Chem. Rev. 1994, 137, 403 and references therein.
2. For some group 3 and lanthanide complexes, see: (a) Edelmann, F. T.; Richter, J. Eur. J. Solid State Inorg. Chem. 1996, 33, 157. (b) Hagardon, J. R., Arnold, J. Organometallics 1996, 15, 984. (c) Edelmann, F. T. Top. Curr. Chem. 1996, 179, 113 and references therein, (d) Duchateau, R.; van Wee, C. T.; Meetsma, A.; van Duijnen, P. Th.; Teuben, J. H. Organometallics 1996, 15, 2279. (e) Duchateau, R.; van Wee, C. T.; Teuben, J. H. Organometallics 1996, 15, 2291. (f) Edelmann, F. T. Coord. Chem. Rev. 1994, 137, 403 and references therein.
3. For some group 3 and lanthanide complexes, see: (a) Edelmann, F. T.; Richter, J. Eur. J. Solid State Inorg. Chem. 1996, 33, 157. (b) Hagardon, J. R., Arnold, J. Organometallics 1996, 15, 984. (c) Edelmann, F. T. Top. Curr. Chem. 1996, 179, 113 and references therein, (d) Duchateau, R.; van Wee, C. T.; Meetsma, A.; van Duijnen, P. Th.; Teuben, J. H. Organometallics 1996, 15, 2279. (e) Duchateau, R.; van Wee, C. T.; Teuben, J. H. Organometallics 1996, 15, 2291. (f) Edelmann, F. T. Coord. Chem. Rev. 1994, 137, 403 and references therein.
4. For some group 3 and lanthanide complexes, see: (a) Edelmann, F. T.; Richter, J. Eur. J. Solid State Inorg. Chem. 1996, 33, 157. (b) Hagardon, J. R., Arnold, J. Organometallics 1996, 15, 984. (c) Edelmann, F. T. Top. Curr. Chem. 1996, 179, 113 and references therein, (d) Duchateau, R.; van Wee, C. T.; Meetsma, A.; van Duijnen, P. Th.; Teuben, J. H. Organometallics 1996, 15, 2279. (e) Duchateau, R.; van Wee, C. T.; Teuben, J. H. Organometallics 1996, 15, 2291. (f) Edelmann, F. T. Coord. Chem. Rev. 1994, 137, 403 and references therein.
5. For some group 3 and lanthanide complexes, see: (a) Edelmann, F. T.; Richter, J. Eur. J. Solid State Inorg. Chem. 1996, 33, 157. (b) Hagardon, J. R., Arnold, J. Organometallics 1996, 15, 984. (c) Edelmann, F. T. Top. Curr. Chem. 1996, 179, 113 and references therein, (d) Duchateau, R.; van Wee, C. T.; Meetsma, A.; van Duijnen, P. Th.; Teuben, J. H. Organometallics 1996, 15, 2279. (e) Duchateau, R.; van Wee, C. T.; Teuben, J. H. Organometallics 1996, 15, 2291. (f) Edelmann, F. T. Coord. Chem. Rev. 1994, 137, 403 and references therein.
6. For some group 3 and lanthanide complexes, see: (a) Edelmann, F. T.; Richter, J. Eur. J. Solid State Inorg. Chem. 1996, 33, 157. (b) Hagardon, J. R., Arnold, J. Organometallics 1996, 15, 984. (c) Edelmann, F. T. Top. Curr. Chem. 1996, 179, 113 and references therein, (d) Duchateau, R.; van Wee, C. T.; Meetsma, A.; van Duijnen, P. Th.; Teuben, J. H. Organometallics 1996, 15, 2279. (e) Duchateau, R.; van Wee, C. T.; Teuben, J. H. Organometallics 1996, 15, 2291. (f) Edelmann, F. T. Coord. Chem. Rev. 1994, 137, 403 and references therein.
7. For group 4 complexes, see: (a) Müeller, E.; Müeller, J.; Olbrich, F.; Bruser, W.; Knapp, W.; Abeln, D.; Edelmann, F. T. Eur. J. Inorg. Chem. 1998, 87. (b) Stewart, P. J.; Blake, A. J.; Mountford, P. Organometallics 1998, 17, 3271. (c) Hagardon, J. R.; Arnold, J. Organometallics 1998, 17, 1355. (d) Hagardon, J. R.; Arnold, J. Inorg. Chem. 1997, 36, 2928. (e) Ciruelo, G.; Cuenca, T.; Gomez, R.; Gomez-Sal, P.; Martin, A.; Rodriguez, G.; Royo, P. J. Organomet. Chem. 1997, 547, 287. (f) Hagardon, J. R.; Arnold, J. J. Chem. Soc., Dalton Trans. 1997, 3087. (g) Richter, J.; Belay, M.; Brieser, W.; Edelmann, F. T. Main Group Met. Chem. 1997, 20, 191. (h) Hagardon, J. R.; Arnold, J. J. Am. Chem. Soc. 1996, 118, 893. (i) Gomez, R.; Green, M. L. H.; Haggitt, J. L. J. Chem. Soc., Dalton Trans. 1996, 939 and references therein.
8. For group 4 complexes, see: (a) Müeller, E.; Müeller, J.; Olbrich, F.; Bruser, W.; Knapp, W.; Abeln, D.; Edelmann, F. T. Eur. J. Inorg. Chem. 1998, 87. (b) Stewart, P. J.; Blake, A. J.; Mountford, P. Organometallics 1998, 17, 3271. (c) Hagardon, J. R.; Arnold, J. Organometallics 1998, 17, 1355. (d) Hagardon, J. R.; Arnold, J. Inorg. Chem. 1997, 36, 2928. (e) Ciruelo, G.; Cuenca, T.; Gomez, R.; Gomez-Sal, P.; Martin, A.; Rodriguez, G.; Royo, P. J. Organomet. Chem. 1997, 547, 287. (f) Hagardon, J. R.; Arnold, J. J. Chem. Soc., Dalton Trans. 1997, 3087. (g) Richter, J.; Belay, M.; Brieser, W.; Edelmann, F. T. Main Group Met. Chem. 1997, 20, 191. (h) Hagardon, J. R.; Arnold, J. J. Am. Chem. Soc. 1996, 118, 893. (i) Gomez, R.; Green, M. L. H.; Haggitt, J. L. J. Chem. Soc., Dalton Trans. 1996, 939 and references therein.
9. For group 4 complexes, see: (a) Müeller, E.; Müeller, J.; Olbrich, F.; Bruser, W.; Knapp, W.; Abeln, D.; Edelmann, F. T. Eur. J. Inorg. Chem. 1998, 87. (b) Stewart, P. J.; Blake, A. J.; Mountford, P. Organometallics 1998, 17, 3271. (c) Hagardon, J. R.; Arnold, J. Organometallics 1998, 17, 1355. (d) Hagardon, J. R.; Arnold, J. Inorg. Chem. 1997, 36, 2928. (e) Ciruelo, G.; Cuenca, T.; Gomez, R.; Gomez-Sal, P.; Martin, A.; Rodriguez, G.; Royo, P. J. Organomet. Chem. 1997, 547, 287. (f) Hagardon, J. R.; Arnold, J. J. Chem. Soc., Dalton Trans. 1997, 3087. (g) Richter, J.; Belay, M.; Brieser, W.; Edelmann, F. T. Main Group Met. Chem. 1997, 20, 191. (h) Hagardon, J. R.; Arnold, J. J. Am. Chem. Soc. 1996, 118, 893. (i) Gomez, R.; Green, M. L. H.; Haggitt, J. L. J. Chem. Soc., Dalton Trans. 1996, 939 and references therein.
10. For group 4 complexes, see: (a) Müeller, E.; Müeller, J.; Olbrich, F.; Bruser, W.; Knapp, W.; Abeln, D.; Edelmann, F. T. Eur. J. Inorg. Chem. 1998, 87. (b) Stewart, P. J.; Blake, A. J.; Mountford, P. Organometallics 1998, 17, 3271. (c) Hagardon, J. R.; Arnold, J. Organometallics 1998, 17, 1355. (d) Hagardon, J. R.; Arnold, J. Inorg. Chem. 1997, 36, 2928. (e) Ciruelo, G.; Cuenca, T.; Gomez, R.; Gomez-Sal, P.; Martin, A.; Rodriguez, G.; Royo, P. J. Organomet. Chem. 1997, 547, 287. (f) Hagardon, J. R.; Arnold, J. J. Chem. Soc., Dalton Trans. 1997, 3087. (g) Richter, J.; Belay, M.; Brieser, W.; Edelmann, F. T. Main Group Met. Chem. 1997, 20, 191. (h) Hagardon, J. R.; Arnold, J. J. Am. Chem. Soc. 1996, 118, 893. (i) Gomez, R.; Green, M. L. H.; Haggitt, J. L. J. Chem. Soc., Dalton Trans. 1996, 939 and references therein.
11. For group 4 complexes, see: (a) Müeller, E.; Müeller, J.; Olbrich, F.; Bruser, W.; Knapp, W.; Abeln, D.; Edelmann, F. T. Eur. J. Inorg. Chem. 1998, 87. (b) Stewart, P. J.; Blake, A. J.; Mountford, P. Organometallics 1998, 17, 3271. (c) Hagardon, J. R.; Arnold, J. Organometallics 1998, 17, 1355. (d) Hagardon, J. R.; Arnold, J. Inorg. Chem. 1997, 36, 2928. (e) Ciruelo, G.; Cuenca, T.; Gomez, R.; Gomez-Sal, P.; Martin, A.; Rodriguez, G.; Royo, P. J. Organomet. Chem. 1997, 547, 287. (f) Hagardon, J. R.; Arnold, J. J. Chem. Soc., Dalton Trans. 1997, 3087. (g) Richter, J.; Belay, M.; Brieser, W.; Edelmann, F. T. Main Group Met. Chem. 1997, 20, 191. (h) Hagardon, J. R.; Arnold, J. J. Am. Chem. Soc. 1996, 118, 893. (i) Gomez, R.; Green, M. L. H.; Haggitt, J. L. J. Chem. Soc., Dalton Trans. 1996, 939 and references therein.
12. For group 4 complexes, see: (a) Müeller, E.; Müeller, J.; Olbrich, F.; Bruser, W.; Knapp, W.; Abeln, D.; Edelmann, F. T. Eur. J. Inorg. Chem. 1998, 87. (b) Stewart, P. J.; Blake, A. J.; Mountford, P. Organometallics 1998, 17, 3271. (c) Hagardon, J. R.; Arnold, J. Organometallics 1998, 17, 1355. (d) Hagardon, J. R.; Arnold, J. Inorg. Chem. 1997, 36, 2928. (e) Ciruelo, G.; Cuenca, T.; Gomez, R.; Gomez-Sal, P.; Martin, A.; Rodriguez, G.; Royo, P. J. Organomet. Chem. 1997, 547, 287. (f) Hagardon, J. R.; Arnold, J. J. Chem. Soc., Dalton Trans. 1997, 3087. (g) Richter, J.; Belay, M.; Brieser, W.; Edelmann, F. T. Main Group Met. Chem. 1997, 20, 191. (h) Hagardon, J. R.; Arnold, J. J. Am. Chem. Soc. 1996, 118, 893. (i) Gomez, R.; Green, M. L. H.; Haggitt, J. L. J. Chem. Soc., Dalton Trans. 1996, 939 and references therein.
13. For group 4 complexes, see: (a) Müeller, E.; Müeller, J.; Olbrich, F.; Bruser, W.; Knapp, W.; Abeln, D.; Edelmann, F. T. Eur. J. Inorg. Chem. 1998, 87. (b) Stewart, P. J.; Blake, A. J.; Mountford, P. Organometallics 1998, 17, 3271. (c) Hagardon, J. R.; Arnold, J. Organometallics 1998, 17, 1355. (d) Hagardon, J. R.; Arnold, J. Inorg. Chem. 1997, 36, 2928. (e) Ciruelo, G.; Cuenca, T.; Gomez, R.; Gomez-Sal, P.; Martin, A.; Rodriguez, G.; Royo, P. J. Organomet. Chem. 1997, 547, 287. (f) Hagardon, J. R.; Arnold, J. J. Chem. Soc., Dalton Trans. 1997, 3087. (g) Richter, J.; Belay, M.; Brieser, W.; Edelmann, F. T. Main Group Met. Chem. 1997, 20, 191. (h) Hagardon, J. R.; Arnold, J. J. Am. Chem. Soc. 1996, 118, 893. (i) Gomez, R.; Green, M. L. H.; Haggitt, J. L. J. Chem. Soc., Dalton Trans. 1996, 939 and references therein.
14. For group 4 complexes, see: (a) Müeller, E.; Müeller, J.; Olbrich, F.; Bruser, W.; Knapp, W.; Abeln, D.; Edelmann, F. T. Eur. J. Inorg. Chem. 1998, 87. (b) Stewart, P. J.; Blake, A. J.; Mountford, P. Organometallics 1998, 17, 3271. (c) Hagardon, J. R.; Arnold, J. Organometallics 1998, 17, 1355. (d) Hagardon, J. R.; Arnold, J. Inorg. Chem. 1997, 36, 2928. (e) Ciruelo, G.; Cuenca, T.; Gomez, R.; Gomez-Sal, P.; Martin, A.; Rodriguez, G.; Royo, P. J. Organomet. Chem. 1997, 547, 287. (f) Hagardon, J. R.; Arnold, J. J. Chem. Soc., Dalton Trans. 1997, 3087. (g) Richter, J.; Belay, M.; Brieser, W.; Edelmann, F. T. Main Group Met. Chem. 1997, 20, 191. (h) Hagardon, J. R.; Arnold, J. J. Am. Chem. Soc. 1996, 118, 893. (i) Gomez, R.; Green, M. L. H.; Haggitt, J. L. J. Chem. Soc., Dalton Trans. 1996, 939 and references therein.
15. For group 4 complexes, see: (a) Müeller, E.; Müeller, J.; Olbrich, F.; Bruser, W.; Knapp, W.; Abeln, D.; Edelmann, F. T. Eur. J. Inorg. Chem. 1998, 87. (b) Stewart, P. J.; Blake, A. J.; Mountford, P. Organometallics 1998, 17, 3271. (c) Hagardon, J. R.; Arnold, J. Organometallics 1998, 17, 1355. (d) Hagardon, J. R.; Arnold, J. Inorg. Chem. 1997, 36, 2928. (e) Ciruelo, G.; Cuenca, T.; Gomez, R.; Gomez-Sal, P.; Martin, A.; Rodriguez, G.; Royo, P. J. Organomet. Chem. 1997, 547, 287. (f) Hagardon, J. R.; Arnold, J. J. Chem. Soc., Dalton Trans. 1997, 3087. (g) Richter, J.; Belay, M.; Brieser, W.; Edelmann, F. T. Main Group Met. Chem. 1997, 20, 191. (h) Hagardon, J. R.; Arnold, J. J. Am. Chem. Soc. 1996, 118, 893. (i) Gomez, R.; Green, M. L. H.; Haggitt, J. L. J. Chem. Soc., Dalton Trans. 1996, 939 and references therein.
16. For group 5 complexes, see: (j) Brussee, E. A. C.; Meetsma, A.; Hessen, B.; Teuben, J. H. Organometallics, 1998, 17, 4090. (k) Stewart, P. J.; Blake, A. J.; Mountford, P. Inorg. Chem. 1997, 36, 1982. (l) Dawson, D. Y.; Arnold, J. Organometallics, 1997, 16, 1111.
17. For group 5 complexes, see: (j) Brussee, E. A. C.; Meetsma, A.; Hessen, B.; Teuben, J. H. Organometallics, 1998, 17, 4090. (k) Stewart, P. J.; Blake, A. J.; Mountford, P. Inorg. Chem. 1997, 36, 1982. (l) Dawson, D. Y.; Arnold, J. Organometallics, 1997, 16, 1111.
18. For group 5 complexes, see: (j) Brussee, E. A. C.; Meetsma, A.; Hessen, B.; Teuben, J. H. Organometallics, 1998, 17, 4090. (k) Stewart, P. J.; Blake, A. J.; Mountford, P. Inorg. Chem. 1997, 36, 1982. (l) Dawson, D. Y.; Arnold, J. Organometallics, 1997, 16, 1111.
19. For group 13 complexes, see: (m) Duchateau, R.; Meetsma, A,; Teuben, J. H. J. Chem. Soc., Chem. Comun. 1996, 223. (n) Barker, J.; Blacker, N. C.; Phillips, P. R.; Alock, N. W.; Errington, W.; Wallbridge, M. G. H. J. Chem. Soc., Dalton Trans. 1996, 431.
20. For group 13 complexes, see: (m) Duchateau, R.; Meetsma, A,; Teuben, J. H. J. Chem. Soc., Chem. Comun. 1996, 223. (n) Barker, J.; Blacker, N. C.; Phillips, P. R.; Alock, N. W.; Errington, W.; Wallbridge, M. G. H. J. Chem. Soc., Dalton Trans. 1996, 431.
21. (a) Richter, J.; Edelmann, F. T.; Noltemeyer, M.; Schmidt, H.-G.; Shmulinson, M.; Eisen, M. S. J. Mol. Catal. Part A 1998, 130, 149.
22. (b) Flores, J. C.; Chien, J. C. W.; Rausch, M. D. Organometallics 1995, 14, 1827.
23. (c) Walther, D.; Fischer, R.; Görls, H.; Koch, J.; Schweder, B. J. Organomet. Chem. 1996, 508, 13.
24. (d) Walther, D.; Fischer, R.; Friedrich, F.; Gebhardt, P.; Görls, H. Chem. Ber. 1996, 129, 1389.
25. (e) Gómez, R.; Duchateau, R.; Chernega, A. N.; Meetsma, A.; Edelmann, F. T.; Teuben, J. H.; Green, M. L. H. J. Chem. Soc., Dalton Trans. 1995, 217.
26. (f) Herskovics-Korine, D.; Eisen, M. S. J. Organomet. Chem. 1995, 503, 307.
27. Volkis, V.; Shmulinson, M.; Averbuj, C.; Lisovskii, A.; Edelmann, F. T.; Eisen, M. S. Organometallics 1998, 17, 3155.
28. (a) Busico, V.; Cipullo, R.; Caporaso, L.; Angelini, G.; Segre, A. L. J. Mol. Catal. Part A 1998, 128, 53 and references therein.
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30. (c) Busico, V.; Caporaso, L.; Cipullo, R.; Landriani, L.; Angelini, G.; Margonelli, A. Segre, A. L. J. Am. Chem. Soc. 1996, 118, 2105.
31. (d) Leclerc, M.; Brinzinger, H. H. J. Am. Chem. Soc. 1996, 118, 9024 and references therein.
32. (e) Leclerc, M.; Brinzinger, H. H. J. Am. Chem. Soc. 1995, 117, 1651.
33. (f) Busico, V.; Cipullo, R. J. Am. Chem. Soc. 1994, 116, 9329.
34. The stoichiometric isomerization of olefins via the hydrozirconation reaction is well-known, see: (a) Schwartz, J. Pure Appl. Chem. 1980, 52, 733 and references therein. (b) Schwanz, J.; Labinger, J. A. Angew. Chem., Int. Ed. Engl. 1976, 15, 333 and references therein, (c) Hart, D. W.; Schwartz, J. J. Am. Chem. Soc. 1974, 96, 8115.
35. The stoichiometric isomerization of olefins via the hydrozirconation reaction is well-known, see: (a) Schwartz, J. Pure Appl. Chem. 1980, 52, 733 and references therein. (b) Schwanz, J.; Labinger, J. A. Angew. Chem., Int. Ed. Engl. 1976, 15, 333 and references therein, (c) Hart, D. W.; Schwartz, J. J. Am. Chem. Soc. 1974, 96, 8115.
36. The stoichiometric isomerization of olefins via the hydrozirconation reaction is well-known, see: (a) Schwartz, J. Pure Appl. Chem. 1980, 52, 733 and references therein. (b) Schwanz, J.; Labinger, J. A. Angew. Chem., Int. Ed. Engl. 1976, 15, 333 and references therein, (c) Hart, D. W.; Schwartz, J. J. Am. Chem. Soc. 1974, 96, 8115.
37. For group 4 complexes, the catalytic isomerization of alkenes is known only for low-valent complexes, see: (a) Ohff, A.; Burlakov, V. V.; Rosenthal, U. J. Mol. Catal. Part A 1996, 105, 103. (b) Rao, S. A.; Periasamy, M. J. Organomet. Chem. 1988, 342, 15 (c) Yanlong, Q.; Jiaqui, L.; Weihua, X. J. Mol. Catal. 1986, 34, 31. (d) Cohen, S. A.; Auburn, P. R.; Bercaw, J. E. J. Am. Chem. Soc. 1983, 705, 1136.
38. For group 4 complexes, the catalytic isomerization of alkenes is known only for low-valent complexes, see: (a) Ohff, A.; Burlakov, V. V.; Rosenthal, U. J. Mol. Catal. Part A 1996, 105, 103. (b) Rao, S. A.; Periasamy, M. J. Organomet. Chem. 1988, 342, 15 (c) Yanlong, Q.; Jiaqui, L.; Weihua, X. J. Mol. Catal. 1986, 34, 31. (d) Cohen, S. A.; Auburn, P. R.; Bercaw, J. E. J. Am. Chem. Soc. 1983, 705, 1136.
39. For group 4 complexes, the catalytic isomerization of alkenes is known only for low-valent complexes, see: (a) Ohff, A.; Burlakov, V. V.; Rosenthal, U. J. Mol. Catal. Part A 1996, 105, 103. (b) Rao, S. A.; Periasamy, M. J. Organomet. Chem. 1988, 342, 15 (c) Yanlong, Q.; Jiaqui, L.; Weihua, X. J. Mol. Catal. 1986, 34, 31. (d) Cohen, S. A.; Auburn, P. R.; Bercaw, J. E. J. Am. Chem. Soc. 1983, 705, 1136.
40. For group 4 complexes, the catalytic isomerization of alkenes is known only for low-valent complexes, see: (a) Ohff, A.; Burlakov, V. V.; Rosenthal, U. J. Mol. Catal. Part A 1996, 105, 103. (b) Rao, S. A.; Periasamy, M. J. Organomet. Chem. 1988, 342, 15 (c) Yanlong, Q.; Jiaqui, L.; Weihua, X. J. Mol. Catal. 1986, 34, 31. (d) Cohen, S. A.; Auburn, P. R.; Bercaw, J. E. J. Am. Chem. Soc. 1983, 705, 1136.
41. Averbuj, C.; Tish, E.; Eisen, M. S. J. Am. Chem. Soc. 1998, 120, 8640.
42. See refs 4 and 7 for the formation of the corresponding cationic benzamidinate complexes.
43. 2-Methyl-1-cctene is also an expected isomer although it was not detected either due to a difference in reactivity favoring the 2,1-insertion or because the methyl elimination of such an organometallic moiety is much faster than the β-hydrogen elimination. For the polymerization of propylene catalyzed by octahedral complexes we have shown that the methyl elimination is the only effective termination pathway at atmospheric pressure. See ref 4.
44. The 1,4-elimination producing benzene is favored over an isomerization of the organometallic complex with consecutive 1,2-elimination. If isomerization occurs before the elimination, an intermediate complex similar to the one obtained for the disproportionation of 1,3-cyclohexadiene would be expected, leading also to oligomeric products. For favoring 1,4-eliminations over 1,2-eliminations in alicyclic compounds see: Mandelbaum, A. Mass Spectrom. Rev. 1983, 2, 223.
45. In Scheme 2, the allylic activation of either complexes D and E by cyclohexene is possible, although it seems not to be a competing reaction since complex F would be formed allowing oligomerization products.
46. Crabtree, R. H. In The Organometallic Chemistry of the Transition Metals; John Wiley & Sons Inc.: New York, 1988; Chapter 9.
47. No isomerization products were observed in blank reactions, performed under the same conditions, for both olefin and cyclic olefins with MAO.
48. (a) The Aldrich Library of NMR Spectra; Pouchert, C. J., II, Ed.; Aldrich Chemical Co.: Milwaukee, WI; 1983; Vols. 1, 2.
49. 1H FT NMR Spectra; Pouchert, C. J., Behnke, J. Eds.; Aldrich Chemical Co.: Wilwaukee, WI; 1993.