Computational study of reductive elimination reactions to form C-H bonds from platinum(II) and platinum(IV) centers with strongly coordinating trimethylphosphine ligands

Organometallics

Volumn 20, Issue 13, 2001, Pages 2669-2678

  Bartlett, Kevin L ^a   Goldberg, Karen I ^a   Borden, Weston Thatcher ^a  

^a UNIVERSITY OF WASHINGTON   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CALCULATIONS; CHELATION; CHEMICAL BONDS; COMPLEXATION; COMPUTER SIMULATION; ENTHALPY; ISOMERS; METHANE; PLATINUM COMPOUNDS; REACTION KINETICS; REDUCTION;

REDUCTIVE ELIMINATION REACTIONS; SOFTWARE PACKAGE B3LYP; TRIMETHYLPHOSPHINE LIGANDS;

ORGANOMETALLICS;

EID: 0035948482     PISSN: 02767333     EISSN: None     Source Type: Journal    
DOI: 10.1021/om010072e     Document Type: Article

References (56)

1. Collman, J. P.; Hegedus, L. S.; Norton, J. R.; Finke, R. G. Principles and Applications of Organotransition Metal Chemistry; University Science Books: Mill Valley, CA, 1987.
2. Alkyl C-C elimination from Pt(II): DiCosimo, R.; Whitesides, G. M. J. Am. Chem. Soc. 1982, 104, 3601.
3. Alkyl C-H elimination from Pt(II): (a) Michelin, R. A.; Faglia, S.; Uguagliati, P. Inorg. Chem. 1983, 22, 1831.
4. (b) Abis, L.; Sen, A.; Halpern, J. J. Am. Chem. Soc. 1978, 100, 2915.
5. Alkyl C-C elimination from Pt(IV): (a) Crumpton, D. M.; Goldberg, K. I. J. Am. Chem. Soc. 2000, 122, 962.
6. (b) Williams, B. S.; Holland, A. W.; Goldberg, K. I. J. Am. Chem. Soc. 1999, 121, 252.
7. (c) Hill, G. S.; Yap, G. P. A.; Puddephatt, R. J. Organometallics 1999, 18, 1408.
8. (d) Goldberg, K. I.; Yan, J. Y.; Breitung, E. M. J. Am. Chem. Soc. 1995, 117, 6889.
9. van Asselt, R.; Rijnberg, E.; Elsevier, C. J. Organometallics 1994, 13, 706.
10. (f) Roy, S.; Puddephatt, R. J.; Scott, J. D. J. Chem. Soc., Dalton Trans. 1989, 2121.
11. (g) Brown, M. P.; Puddephatt, R. J.; Upton, C. E. E. J. Chem. Soc., Dalton Trans. 1974, 2457.
12. (h) Williams, B. S.; Goldberg, K. I. J. Am. Chem. Soc. 2001, 123, 2576.
13. Alkyl C-H elimination from Pt(IV): (a) Heiberg, H.; Johansson, L.; Gropen, O.; Ryan, O. B.; Swang, O.; Tilset, M. J. Am. Chem. Soc. 2000, 122, 10831.
14. (b) Johansson, L.; Tilset, M.; Labinger, J. A.; Bercaw, J. E. J. Am. Chem. Soc. 2000, 122, 10846.
15. (c) Reinartz, S.; White, P. S.; Brookhart, M.; Templeton, J. L. Organometallics 2000, 19, 3854.
16. (d) Fekl, U.; Zahl, A.; van Eldik, R. Organometallics 1999, 18, 4156.
17. (e) Jenkins, H. A.; Yap, G. P. A.; Puddephatt, R. J. Organometallics 1997, 16, 1946.
18. (f) Hill, G. S.; Vittal, J. J.; Puddephatt, R. J. Organometallics 1997, 16, 1209.
19. (g) Stahl, S. S.; Labinger, J. A.; Bercaw, J. E. J. Am. Chem. Soc. 1996, 118, 5961.
20. (h) O'Reilly, S. A.; White, P. S.; Templeton, J. L. J. Am. Chem. Soc. 1996, 118, 5684.
21. (i) Hill, G. S.; Rendina, L. M.; Puddephatt, R. J. Organometallics 1995, 14, 4966.
22. Theoretical investigations of reductive elimination from Pt(II) and Pt(IV): (a) Dedieu, A. Chem. Rev. 2000, 100, 543.
23. (b) Bartlett, K. L.; Goldberg, K. I.; Borden, W. T. J. Am. Chem. Soc. 2000, 122, 1456.
24. (c) Mylvaganam, K.; Bacskay, G. B.; Hush, N. S. J. Am. Chem. Soc. 2000, 122, 2041.
25. (d) Mylvaganam, K.; Bacskay, G. B.; Hush, N. S. J. Am. Chem. Soc. 1999, 121, 4633.
26. (e) Hill, G. S.; Puddephatt, R. J. Organometallics 1998, 17, 1478.
27. (f) Su, M.-D. Chu, S.-Y. Inorg. Chem. 1998, 37, 3400.
28. (g) Siegbahn, P. E. M.; Crabtree, R. H. J. Am. Chem. Soc. 1996, 118, 4442.
29. (h) Low, J. J.; Goddard, W. A., III. J. Am. Chem. Soc. 1986, 108, 6115.
30. (i) Low, J. J.; Goddard, W. A., III. Organometallics 1986, 5, 609.
31. (j) Obara, S.; Kitaura, K.; Morokuma, K. J. Am. Chem. Soc. 1984, 106, 7482.
32. Balazs, A. C.; Johnson, K. H.; Whitesides, G. M. Inorg. Chem. 1982, 21, 2162.
33. (l) Hoffmann, R. In Frontiers of Chemistry; Laidler, K. J., Ed.; Pergamon Press: Oxford, 1982; p 247.
34. (m) Tatsumi, K.; Hoffmann, R.; Yamamoto, A.; Stille, J. K. Bull. Chem. Soc. Jpn. 1981, 54, 1857.
35. +.
36. (b) Staley, R. H.; Beauchamp, J. L. J. Am. Chem. Soc. 1974, 96, 6252.
37. (c) Henderson, W. A.; Streuli, C. A. J. Am. Chem. Soc. 1960, 82, 5791.
38. (d) Weston, R. E.; Bigeleisen, J. J. Am. Chem. Soc. 1954, 76, 3074.
39. 1 symmetry and analytical second derivatives were calculated at each step in the geometry optimizations.
40. Becke, A. D. J. Chem. Phys. 1993, 98, 5648.
41. (a) Lee, C.; Yang, W.; Parr, R. G. Phys. Rev. B 1988, 37, 785.
42. (b) Miehlich, B.; Savin, A.; Stoll, H.; Preuss, H. Chem. Phys. Lett. 1989, 157, 200.
43. The enthalpies required for six phosphine dissociation reactions were higher by 6.1 ± 0.7 kcal/mol at CCSD(T) than at B3LYP, prior to correction for basis-set superposition error (BSSE). After correction, the average of the differences between the B3LYP and CCSD(T) dissociation enthalpies was only 0.1 kcal/mol, and the root-mean-square difference was ±0.7 kcal/mol. (See the Supporting Information for ref 6b.)
44. Kestner, N. R.; Combariza, J. E. In Lipkowitz, K. B.; Boyd, D. B. Reviews in Computational Chemistry; Wiley-VCH: New York 1999; Vol. 13, pp 99-132.
45. Stevens, W. J.; Krauss, M.; Bausch, H.; Jasien, P. G. Can. J. Chem. 1992, 70, 612.
46. Dunning, T. H., Jr.; Hay, P. J. In Modern Theoretical Chemistry; Schaefer, H. F., III, Ed.; Plenum: New York, 1976; pp 1-28.
47. Computed entropic contributions to the gas-phase free energies are available in the Supporting Information. Unfortunately, the gas-phase entropies are not the same as the solution-phase entropies, which are chemically relevant. In addition, the use of harmonic oscillator partition functions by Gaussian 98 for the low-frequency, hindered rotations in the complexes in this article makes the accuracy of even the gas-phase entropies suspect. Consequently, the computed entropic contributions to free energies are not discussed in the text.
48. Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E. Robb, M. A.; Cheeseman, J. R.; Zakrzewski, V. G.; Montgomery, J. A. Jr.; Stratmann, R. E.; Burant, J. C.; Dapprich, S.; Millam, J. M.; Daniels, A. D.; Kudin, K. N.; Strain, M. C.; Farkas, O.; Tomasi, J.; Barone, V.; Cossi, M.; Cammi, R.; Mennucci, B.; Pomelli, B.; Adamo, C.; Clifford S.; Ochterski, J.; Petersson, G. A.; Ayala, P. Y.; Cui, Q.; Morokuma, K.; Malick, D. K.; Rabuck, A. D.; Raghavachari, K.; Foresman, J. B.; Cioslowski, J.; Ortiz, J. V.; Stefanov, B. B.; Liu, G.; Liashenko, A.; Piskorz, P.; Komaromi, I.; Gomperts, R.; Martin, R. L.; Fox, D. J.; Keith, T.; Al-Laham, M. A.; Peng, C. Y.; Nanayakkara, A.; Gonzalez, C.; Challacombe, M.; Gill, P. M. W.; Johnson, B.; Chen, W.; Wong, M. W.; Andres, J. L.; Gonzalez, C.; Head-Gordon, M.; Replogle, E. S.; Pople, J. A. Gaussian 98 (Revision A.7); Gaussian, Inc.: Pittsburgh, PA, 1998.
49. The graphics used in all the figures were created with the program MacMolPlot, v. 5.2.1, written by Brett Bode. Bode, B. M.; Gordon, M. S. J. Mol. Graphics Mod. 1999, 16, 133.
50. 3 ligated system, 1a, removal of the trimethylphosphine trans to the methyl to form 3b′ required significantly more energy (see Table 1). Attempted reductive elimination of methane from 3b′ caused the phosphine to reorient, yielding 3b prior to methane elimination. The barrier for the isomerization of 3b′ to 3b is 2.8 kcal/mol.
51. The methane binding enthalpies of all reductive elimination complexes have been calculated and corrected for BSSE. As expected, the methane binding enthalpies of the four- and six-coordinate reductive elimination products (2b, 6b, 10b) are negligible. In fact, after adjustment of the electronic energies to enthalpies at 298 K and correction for BSSE, the methane binding enthalpies of these structures are -1.0, -0.9, and -2.5 kcal/mol, respectively, despite the fact that the structures as reported represent electronic energy minima. The methane binding enthalpies of products 4b and 8b are 8.2 and 1.1 kcal/mol, respectively. A comparable methane binding enthalpy could not be calculated for product 13b, since the complex reoriented to place the chloride ligands mutually trans upon removal of the methane, with a significant energetic benefit. As a result, the adiabatic methane binding enthalpy for 13b was computed to be -13.4 kcal/mol.
52. 3 ligand cis to the hydride in 5b forms 7b′. As shown in Table 1, the enthalpy of 7b′ is computed to be 3.5 kcal/mol higher than that of 7b. The barrier for the isomerization of 7b′ to 7b is 0.2 kcal/mol. Methane reductive elimination from 7b′ was found to proceed via initial isomerization to 7b and subsequent elimination.
53. Langford, C. H.; Gray, H. B. Ligand Substitution Processes; W. A. Benjamin, Inc.; New York, 1965.
54. 3 ligand trans to hydride.
55. The greater sensitivity to ligand basicity of 8, compared to 7, is almost certainly due to the fact that 8 binds phosphine more strongly than 7. This is evident from comparing the Pt-P bond lengths in 7b and 8b in Figure 5. The Pt-P bond distance in 7b is 0.270 Å longer than in 8b.
56. 3, which is 3.1 kcal/mol more exothermic than the analogous reaction involving 3a and 3b.