Coenzyme B12 chemical precedent studies: Probing the role of the imidazole base-on motif found in B12-dependent methylmalonyl-CoA mutase

Journal of the American Chemical Society

Volumn 119, Issue 13, 1997, Pages 3057-3067

  Sirovatka, Jeanne M ^a   Finke, Richard G ^a  

^a Department of Environmental and Radiological Health Sciences   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

COBAMAMIDE; METHYLMALONYL COENZYME A MUTASE;

ARTICLE; COMPUTER SIMULATION; ENZYME BINDING; STRUCTURE ACTIVITY RELATION; THERMODYNAMICS; X RAY CRYSTALLOGRAPHY;

EID: 0030912979     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja963380q     Document Type: Article

References (134)

1. 2N-Py (p-(N,N-dimethylamino)pyridine).
2. (a) Mancia, F.; Keep, N. H.; Nakagawa, A.; Leadlay, P. F.; McSweeney, S.; Rasmussen, B.; Böscke, P.; Diat, O.; Evans, P. R. Structure 1996, 4, 339.
3. 2a that "The 2.5 Å long Co-N bond would stabilize the Co(II) species relative to Co(III) . . . .".
4. 12 bound to methionine synthase: Drennan, C. L.; Huang, S.; Drummond, J. T.; Matthews, R. G.; Ludwig, M. L. Science 1994, 266, 1669. (See also the introductory comments about this landmark Paper: Stubbe, J. Science 1994, 266, 1663.)
5. 12 bound to methionine synthase: Drennan, C. L.; Huang, S.; Drummond, J. T.; Matthews, R. G.; Ludwig, M. L. Science 1994, 266, 1669. (See also the introductory comments about this landmark Paper: Stubbe, J. Science 1994, 266, 1663.)
6. 41 Toraya, T. In Metal Ions in Biological Systems; Sigel, H., Siegel, A., Eds.; Marcel Dekker: New York; 1994; Vol. 30, Chapter 8, p 226. (Reference 41 therein is: Kuno, S.; Fukui, S.; Toraya, T. Arch. Biochem. Biophys. 1990, 277, 211.)
7. 41 Toraya, T. In Metal Ions in Biological Systems; Sigel, H., Siegel, A., Eds.; Marcel Dekker: New York; 1994; Vol. 30, Chapter 8, p 226. (Reference 41 therein is: Kuno, S.; Fukui, S.; Toraya, T. Arch. Biochem. Biophys. 1990, 277, 211.)
8. 41 Toraya, T. In Metal Ions in Biological Systems; Sigel, H., Siegel, A., Eds.; Marcel Dekker: New York; 1994; Vol. 30, Chapter 8, p 226. (Reference 41 therein is: Kuno, S.; Fukui, S.; Toraya, T. Arch. Biochem. Biophys. 1990, 277, 211.)
9. (a) Marzilli, L. G. In Bioinorganic Catalysis; Reedijk, J., Ed.; Marcel Dekker: New York, 1993; pp 227-259.
10. a
11. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
12. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
13. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
14. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
15. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
16. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
17. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
18. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
19. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
20. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
21. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
22. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
23. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
24. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
25. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
26. 12 "axial-base problem": (a) Schrauzer, G. N.; Windgassen, R. J. J. Am. Chem. Soc. 1966, 88, 3738. (b) Thusius, D. J. Am. Chem. Soc. 1971, 93, 2629. (c) Toscano, P. J.; Marzilli, L. G. Prog. Inorg. Chem. 1984, 31, 105. (d) Bresciani-Pahor, N.; Forcolin, M.; Marzilli, L. G.; Randaccio, L.; Summers, M. F.; Toscano, P. J. Coord. Chem. Rev. 1985, 63, 1. (e) Randaccio, L; Bresciani-Pahor, N.; Zangrando, E.; Marzilli, L. G. Chem. Soc. Rev. 1989, 18, 225. (f) Grate, J. H.; Schrauzer, G. N. J. Am. Chem. Soc. 1979, 101, 4601. (g) Schrauzer, G. N.; Grate, J. H. J. Am. Chem. Soc. 1981, 103, 541. (h) Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1980, 2274. (i) Brown, K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854. (j) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496. (k) Brown, K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366. (l) Ng, F. T. T.; Rempel, G. L.; Halpem, J. Inorg. Chim. Acta 1983, 77, L165. (m) Halpern, J. Pure Appl. Chem. 1983, 55, 1059. (n) Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621. (o) Ng, F. T. T.; Rempel, G. L.; Mancuso, C.; Halpern, J. Organometallics 1990, 9, 2762. (p) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
27. 3,21).
28. 3,21).
29. 3,21).
30. 3,21).
31. 3,21).
32. 3,21).
33. 3,21).
34. 3,21).
35. 3,21).
36. 3,21).
37. 3,21).
38. 3,21).
39. assoc measurements: (a) Pailes, W. H.; Hogenkamp, H. P. C. Biochemistry 1968, 7, 4160. (b) Baldwin, D. A.; Betterson, E. A.; Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1985, 1613. (c) Brown, K. L.; Brooks, H. B. Inorg. Chem. 1991, 30, 3420. (d) Brodie, J. D. Proc. Natl. Acad. Sci. U.S.A. 1969, 62, 461. (e) Brown, K. L.; Satyanarayana, S. Inorg. Chim. Acta 1992, 201, 113-119. (f) See also ref 38 herein.
40. assoc measurements: (a) Pailes, W. H.; Hogenkamp, H. P. C. Biochemistry 1968, 7, 4160. (b) Baldwin, D. A.; Betterson, E. A.; Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1985, 1613. (c) Brown, K. L.; Brooks, H. B. Inorg. Chem. 1991, 30, 3420. (d) Brodie, J. D. Proc. Natl. Acad. Sci. U.S.A. 1969, 62, 461. (e) Brown, K. L.; Satyanarayana, S. Inorg. Chim. Acta 1992, 201, 113-119. (f) See also ref 38 herein.
41. assoc measurements: (a) Pailes, W. H.; Hogenkamp, H. P. C. Biochemistry 1968, 7, 4160. (b) Baldwin, D. A.; Betterson, E. A.; Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1985, 1613. (c) Brown, K. L.; Brooks, H. B. Inorg. Chem. 1991, 30, 3420. (d) Brodie, J. D. Proc. Natl. Acad. Sci. U.S.A. 1969, 62, 461. (e) Brown, K. L.; Satyanarayana, S. Inorg. Chim. Acta 1992, 201, 113-119. (f) See also ref 38 herein.
42. assoc measurements: (a) Pailes, W. H.; Hogenkamp, H. P. C. Biochemistry 1968, 7, 4160. (b) Baldwin, D. A.; Betterson, E. A.; Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1985, 1613. (c) Brown, K. L.; Brooks, H. B. Inorg. Chem. 1991, 30, 3420. (d) Brodie, J. D. Proc. Natl. Acad. Sci. U.S.A. 1969, 62, 461. (e) Brown, K. L.; Satyanarayana, S. Inorg. Chim. Acta 1992, 201, 113-119. (f) See also ref 38 herein.
43. assoc measurements: (a) Pailes, W. H.; Hogenkamp, H. P. C. Biochemistry 1968, 7, 4160. (b) Baldwin, D. A.; Betterson, E. A.; Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1985, 1613. (c) Brown, K. L.; Brooks, H. B. Inorg. Chem. 1991, 30, 3420. (d) Brodie, J. D. Proc. Natl. Acad. Sci. U.S.A. 1969, 62, 461. (e) Brown, K. L.; Satyanarayana, S. Inorg. Chim. Acta 1992, 201, 113-119. (f) See also ref 38 herein.
44. assoc measurements: (a) Pailes, W. H.; Hogenkamp, H. P. C. Biochemistry 1968, 7, 4160. (b) Baldwin, D. A.; Betterson, E. A.; Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1985, 1613. (c) Brown, K. L.; Brooks, H. B. Inorg. Chem. 1991, 30, 3420. (d) Brodie, J. D. Proc. Natl. Acad. Sci. U.S.A. 1969, 62, 461. (e) Brown, K. L.; Satyanarayana, S. Inorg. Chim. Acta 1992, 201, 113-119. (f) See also ref 38 herein.
45. + are reported.
46. 2N-py, the rate constant for Co-C homolysis increases only 240-fold, while the Co-C heterolysis rate constant increases 8400-fold.
47. 10a the anticipated acid (or, in ROH solvents, ester) product from Co(III) oxidation of the initially produced aldehyde has never been unequivocally characterized.
48. (a) Finke, R. G.; Hay, B. P. Inorg. Chem. 1984, 23, 3041.
49. (b) Hay, B. P.; Finke, R. G. J. Am. Chem. Soc. 1986, 108, 4820.
50. (c) Hay, B. P.; Finke, R. G. J. Am. Chem. Soc. 1987, 109, 8012.
51. (d) Hay, B. P.; Finke, R. G. Polyhedron 1988, 7, 1469.
52. 11g).
53. (f) Waddington, M. D.; Finke, R. G. J. Am. Chem. Soc. 1993, 115, 4629.
54. (g) Garr, C. D.; Finke, R. G. Inorg. Chem. 1993, 32, 4414.
55. -] could have a kinetically dominant rate of Co-C cleavage, a key reason why we chose the simpler system of N-MeIm for these initial studies of imidazole bases.
56. Hay, B. P.; Finke, R. G. J. Am. Chem. Soc. 1987, 109, 8012.
57. (a) Rozantzev, E. G.; Neiman, M. B. Tetrahedron, 1964, 20, 131.
58. (b) Prisbe, E. J.; Smejkal, J.; Verheydwn, J. P. H.; Moffatt, J. G. J. Org. Chem. 1976, 47, 1836.
59. (a) Finke, R. G.; Hay, B. P. Inorg. Chem. 1984, 23, 3041.
60. (b) Hay, B. P.; Finke, R. G. J. Am. Chem. Soc. 1986, 108, 4820.
61. 10a for a listing of the earlier literature of Co-C heterolysis): (a) Gerards, L. E.H.; Bait, S. Recl. Trav. Chim. Pays-Bas 1994, 113, 137 (the full paper). (b) Gerards, L. E. H.; Bait, S. Recl. Trav. Chim. Pays-Bas 1992, 111, 411 (the preliminary communication).
62. 10a for a listing of the earlier literature of Co-C heterolysis): (a) Gerards, L. E.H.; Bait, S. Recl. Trav. Chim. Pays-Bas 1994, 113, 137 (the full paper). (b) Gerards, L. E. H.; Bait, S. Recl. Trav. Chim. Pays-Bas 1992, 111, 411 (the preliminary communication).
63. 10a Hence, chemical precedent studies do not appear to favor Co-C heterolysis for either of the two subclasses of AdoCbl-dependent enzymes.
64. (b) Licht, S.; Gerten, G. J.; Stubbe, J. Science 1996, 271, 477.
65. (c) Booker, S.; Licht, S.; Broderick, J.; Stubbe, J. Biochemistry 1994, 33, 12676.
66. (d) Booker, S.; Stubbe, J. Proc. Natl. Acad. Sci. U.S.A. 1993, 90, 8352.
67. 4 faster Co-C heterolysis in 2′,3′-dideoxyadenosylcobalamin which, unlike AdoCbl, they show can achieve the trans-antiperiplanar Co-Ca-Cβ-O arrangement preferred for Co-C heterolysis.
68. (b) Kräutler, B. In Organic Reactivity: Physical and Biological Aspects; Special Publication No. 148, Golding, B. T., Griffin, R. J., Maskill, H., Eds.; The Royal Society of Chemistry: 1995; pp 209-222.
69. 12-model complexes) that comprise ref 1-27 therein.
70. Mealli, C.; Sabat, M.; Marzilli, L. G. J. Am. Chem. Soc. 1987, 109, 1593.
71. 22
72. (b) Kräutler, B.; Konrat, R.; Stupperich, E.; Färber, G.; Gruber, K.; Kratky, C. Inorg. Chem. 1994, 33, 4128.
73. (a) Brown K. L.; Gupta, B. D. Inorg. Chem. 1990, 29, 3854.
74. (b) Brown, K. L.; Hakimi, J. M. J. Am. Chem. Soc. 1986, 108, 496.
75. (c) Brown K. L.; Satyanarayana, S. Inorg. Chem. 1992, 31, 1366.
76. 12; Dolphin, D., Ed.; John Wiley & Sons: New York, 1982; Vol. 1, p 45.
77. +) seems to be in hand, the uncertainty about the solution vs solid state (and EXAFS vs crystallographic) Co(II)-N distance for Co(II)Cbl, possibly in different conformers, requires further clarification. (a) Sagi, I.; Wirt, M. D.; Chen, E.; Frisbie, S. M.; Chance, M. R. J. Am. Chem. Soc. 1990, 112, 8639. (b) Wirt, M. D.; Sagi, I.; Chen, E.; Frisbie, S. M.; Lee, R.; Chance, M. R. J. Am. Chem. Soc. 1991, 113, 5299. (c) Sagi, I.; Chance, M. R. J. Am. Chem. Soc. 1992, 114, 8061. (d) Kräutler, B.; Konrat, R.; Stupperich, E.; Fäber, G.; Gruber, K.; Kratky, C. Inorg. Chem. 1994, 33, 4128 (see p 4139). (e) Kratky, C.; Fäber, G.; Gruber, K.; Wilson, K.; Dauter, Z.; Nolting, H.-F.; Konrat, R.;
78. 12; Dolphin, D., Ed.; John Wiley & Sons: New York; Vol. 1, Chapter 3.
79. 12; Dolphin, D., Ed.; John Wiley & Sons: New York; Vol. 1, Chapter 3.
80. 12; Dolphin, D., Ed.; John Wiley & Sons: New York; Vol. 1, Chapter 3.
81. 12; Dolphin, D., Ed.; John Wiley & Sons: New York; Vol. 1, Chapter 3.
82. 12; Dolphin, D., Ed.; John Wiley & Sons: New York; Vol. 1, Chapter 3.
83. 12; Dolphin, D., Ed.; John Wiley & Sons: New York; Vol. 1, Chapter 3.
84. (a) Huheey, J. E. Inorganic Chemistry, Principles of Structure and Reactivity; Harper and Row: New York, 1972; p 74, Table 3.6, 2nd column, Co(II) and Co(III) entries.
85. (b) Cotton, F. A.; Wilkinson, G. Advanced Inorganic Chemistry; John Wiley & Sons: New York, 1988; p 1388.
86. 25c
87. d,e
88. (c) Baldwin, D. A.; Betterton, E. A.; Chemaly, S. M.; Pratt, J. M. J. Chem. Soc., Dalton Trans. 1985, 1613. On p 1618 Pratt briefly suggests a five-coordinate, possibly triplet Co(II)Cbl in which cobalt is significantly out of the corrin plane.
89. (d) Calligaris, M.; Nardin, G.; Randaccio, L. J. Chem. Soc., Dalton 1974, 1903.
90. (e) Kennedy, B. J.; Fallon, G. D.; Gatehouse, B. M. K. C.; Murray, K. S. Inorg. Chem. 1984, 23, 580.
91. +.
92. assoc values.
93. 11c
94. (b) See p 4636 in: Waddington, M. D.; Finke, R. G. J. Am. Chem. Soc. 1993, 115, 4629.
95. (a) Finke, R. G.; Hay, B. P. Inorg. Chem. 1984, 23, 3041.
96. (b) Hay, B. P.; Finke, R. G. Polyhedron 1988, 7, 1469.
97. c: Garr, C. D.; Finke, R. G. Inorg. Chem. 1993, 32, 4414.
98. 301 We thank Professors T. Spiro, R. Banerjee, and L. Marzilli for helpful discussions of these points.
99. (b) The Encyclopedia of Chemistry, 2nd ed.; Clark, G. L., Hawley, G. G. Eds.; Van Nostrand and Reinhold Co.: New York, 1996; pp 139-141.
100. (c) Wozniak, W. T.; Spiro, T. G. J. Am. Chem. Soc. 1973, 95, 3402.
101. (d) Galluzi, F.; Garozzo, M.; Ricci, F. F. J. Raman Spec. 1974, 2, 351.
102. (e) Nie, S.; Marzilli, L. G.; Yu, N.-T. J. Am. Chem. Soc. 1989, 111, 9256.
103. 30k
104. (g) Nie, S.; Marzilli, P. A.; Marzilli, L. G.; Yu, N.-T. J. Chem. Soc., Chem. Commun. 1990, 770.
105. (h) Chopra, M.; Hun, T. S. M.; Leung, W.-H.; Yu, N.-T. Inorg. Chem. 1995, 34, 5973.
106. (i) Puckett, J. M., Jr.; Mitchell, M. B.; Hirota, S.; Marzilli, L. G. Inorg. Chem. 1996, 35, 4656.
107. (j) Hirota, S.; Polson, S. M.; Puckett, J. M., Jr; Moore, S. J.; Mitchell, M. B.; Marzilli, L. G. Inorg. Chem. 1996, 35, 5646 and ref 7-9 and 11-14 therein to earlier work in this series.
108. (k) Dong, S.; Padmakumar, R.; Banerjee, R.; Spiro, T. G. J. Am. Chem. Soc. 1996, 118, 9182 ("...Co-C Stretching Frequencies Reflect Bond Strength Changes in Alkyl Cobalamins, but are Unaffected by Trans Ligand Substitution"). Note that the author's use of the term "bond strength" as in the paper's text and title is not intended to mean BDE.
109. 30f elsewhere by, ultimately, equating the bottom portions of Morse and Hooke's Law potential wells; note that this yields a conceptually confusing equation derived for only the ground state, yet which contains a term (the BDE) which requires a difference between higher energy product-and ground-states). Drago also uses bond strength as a ΔH term (i.e., as we suggest above) and provides comments (p 194) discouraging both the attempts themselves and the underlying assumptions behind bond strength vs vibrational frequency shift correlations.
110. 12-model results may still be consistent with one another (and even though they rigorously need not be, since the systems are different), depending upon whether or not transition state effects overwhelm effects on the AdoCbl ground state, as we believe they will (vide supra).
111. (b) Huheey, J. E. Inorganic Chemistry, Principles of Structure and Reactivity; Harper and Row: New York, 1972; p 426.
112. (a) De Ridder, D. J. A.; Zangrando, E.; Bürgi, H.-B. J. Mol. Struct. 1996, 374, 63.
113. 32a he has not considered the effects of the β-ligands, nor the possibility of π effects, in his correlations. For example, the graph on p 81 appears to be misleading, as many readers will (like us) probably interpret the "straight line" therein, instead of as a linear Co-N, Co-C bond length relationship, as a series of different cobalamin domains, based on the different α-ligands, of nearly perpendicular slopes to the line shown.
114. (a) Walsh, C. Enzymatic Reaction Mechanisms; W. H. Freeman: San Francisco, 1979; pp 30-33.
115. (b) Abeles, R. H.; Frey, P. A.; Jencks, W. P. Biochemistry; Jones and Bartlett: Boston, 1992; pp 146-149.
116. (a) Albery, W. J.; Knowles, J. R. Biochemistry 1976, 15, 5627.
117. (b) Albery, W. J.; Knowles, J. R. Biochemistry 1976, 15, 5631.
118. (c) Knowles, J. R.; Albery, W. J. Acc. Chem. Res. 1977, 10, 105.
119. (d) Chin, J. J. Am. Chem. Soc. 1983, 105, 6502.
120. (e) Benner, S. A. Chem. Rev. 1989, 89, 789.
121. Al-Jaff, G.; Silver, J.; Wilson, M. T. Inorg. Chim. Acta 1990, 176, 307.
122. Scheidt, W. R.; Chipman, D. M. J. Am. Chem. Soc. 1986, 108, 1163.
123. (a) Basic MO theory of course dictates that the donor (or acceptor) properties of any ligand also depend on the relative energetics of the conjugate acceptor (or donor).
124. (b) An early paper on conformational preferences of the axial-ligands in metalloporphyrins: Rohmer, M.-M.; Strich, A.; Veillard, A. Theoret. Chim. Acta (Berl.) 1984, 65, 219-231.
125. (c) Hoffmann's classic MO paper on six-coordinate complexes: Hoffmann, R.; Howell, J. M.; Rossi, A. R. J. Am. Chem. Soc. 1976, 98, 2484.
126. 37b destabilizing filled-filled (pπ ↔ dπ) interaction: (Matrix Presented) Note that Veillard only publishes the orbitals of the α-carbons; the full molecular orbitals shown here and in Figure 6 result from the minimization in the Spartan program (as described in the Experimental Section).
127. (a) Pahor, N. B.; Attia, W. M.; Gercmia, S.; Randaccio, L. Acta Crystallogr. 1989, C45, 561. Note the 2.083 to 2.086 Å Co(III)-N(Im) bond lengths in the two RCo(cobaloxime)(1,2-dimethylimidazole) structures determined therein.
128. (b) Bigotto, A.; Zangrando, E.; Randaccio, L.; J. Chem. Soc., Dalton Trans. 1976, 96. Note also the 0.01 Å shorter Co-N bond distance therein for N-MeIm vs pyridine as the base in MeCo(cobaloxime)-(base).
129. (c) The only Co-C BDE where imidazole is the trans-axial ligand is for PhCH(Me)Co(cobaloxime)(Im): Ng, F. T. T.; Rempel, G. L.; Halpern, J. J. Am. Chem. Soc. 1982, 104, 621 (see entry 6 in Table 1).
130. (d) Marques, H. M.; Marsh, J. H.; Mellor, J. R.; Munro, O. Q. Inorg. Chim. Acta 1990, 170, 259.
131. + product complexes.
132. 12 to the work of others on this issue.
133. (b) The finding of a six-, not five-, coordinate, solvated complex is just what organometallic chemistry has found in other systems and thus predicts, see: Strauss, S. Chem. Rev. 1993, 93, 927.
134. (c) 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; see p 250 and references therein.