文档介绍：Dinitrogen Scission by a
Molybdenum(III) plex
Dr. Mircea D. hiu
1. Introduction.
2. About Dinitrogen.
3. Nitrogen Fixation. Haber-Bosch ammonia synthesis.
Nitrogenase.
4. Dinitrogen binding and scission. Mechanism.
5. Why dinitrogen is activated by Mo(III) Complexes?
6. Starting materials.
7. Synthesis of the molydenum precursors and the ligand.
8. NMR of pounds.
9. Concluding remarks and future developments.
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The main reference:

Dinitrogen Cleavage by Three-Coordinate
Molybdenum(llI) Complexes: Mechanistic and
Structural Data

Catalina E. Laplaza, Marc J. A. Johnson, Jonas C.
Peters, Aaron L. Odom, Esther Kim, Christopher C.
Cummins, Graham N. e, and Ingrid J. Pickering;
J. Am. Chem. Soc. 1996,118, 8623-863
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An excerpt from the Kit’s paper
references section:

(1) Dedicated to Professor Alan Davison of
the MIT Department of Chemistry on the
occasion of his 60th birthday.

(2) Laplaza, C. E.; Odom, A. L.; Davis, W. M.;
Cummins, C. C.; Protasiewicz, J. D. J. Am.
Chem. Soc. 1995, 117, 4999. Laplaza, C. E.;
Davis, W. M.; Cummins, C. C. Angew. Chem.,
Int. Ed. Engl. 1995,34, 2042.

(3) Laplaza, C. E.; Cummins, C. C. Science
1995, 268, 861. See also: Laplaza, C. E.;
Johnson, A. R.; Cummins, C. C. J. Am. Chem.
Soc. 1996, 118, 709.
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(April 1998)
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2. About dinitrogen:
On Earth 4/5 of the volume of atmosphere; Titan
(moon of Saturn) 82-94%. Bp - ºC (O2 -
183 ºC).

The triple bond is very strong:

At 3000 °C do not pose measurable.

Bond energy is 225 kcal/mole.

Combines with other elements only with
difficulty. At high bines
directly with magnesium, titanium, and
aluminum, forming nitrides.
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3. Nitrogen fixation (to nif, niffing):
1. Haber-Bosch (1909, 1913)
(Fe catalyst; 450-650 °C; 200-600 atm):
J
N2 + 3H2 2NH3

Explosives and nitrogen fertilizers.

Half of the total nitrogen input to
agr