2. Ph.D. 2011, Caltech with John E. Bercaw
Prof. Ian A. Tonks
B.A , Columbia University
Ph.D , Caltech with John E. Bercaw
P.D.F , University of Wisconsin-Madison with Clark R. Landis
Assist. Prof. 2013, University of Minnesota
Research interests :
Using early transition metal catalysts for new redox reactions, and understanding how to access early transition metal redox manifolds. 
Investigating cooperative effects in olefin polymerization toward new reactions such as CO2/ethylene copolymerization. 
Exploring fundamental inorganic syntheses involving multimetallic and other potentially redox noninnocent regimes.

3. [2+2+1] Cycloaddition : Pauson-Khand
Pauson-Khand reaction
Many improvements and modifications arose with various metal catalysts (Fe, Ru, W, etc.)
Gibson, S. E., Stevenazzi, A. Angew. Chem., Int. Ed. Engl. 2003, 42, I. U. Khand,G. R. Knox, P. L. Pauson, W. E. Watts, J. Chem. Soc , 36. I. U. Khand, G. R. Knox, P. L. Pauson, W. E. Watts, M. I .Foreman, J. Chem. Soc. Perkin Trans. 1973, 977. Son, S. U.; Choi, D. S.; Chung, Y. K. org. Lett. 2000, 14, F. A. Hicks, N. M. Kablaoui, S. L. Buchwald, J. Am. Chem.
Soc. 1996, 118, 9450

4. [2+2+1] Cycloaddition : Pauson-Khand
Hochimoto, Y.; Ohata, T.; Sasaoka, Y.;Ohashi, M.; Ogoshi, S. J. Am. Chem. Soc. 2014, 136, Fukuyama, T.; Nakashima, N.; Okada, T.; Ryu, I. J. Am. Chem. Soc. 2013, 135, Iwata, T.; Inagaki F.; Mukai, C. Angew. Chem. Int. Ed. 2013, 52,

5. Titanium Catalyzed Reactions
Ackermann, L.;Sandmann, R.; Kaspar L. T. Org. Lett. 2009, 11, 2031
Kulinkovich, O. G.; Sviridov, S. V.; Vasilevskii, D. A.; Pritytskaya, T. S. Zh. Org. Khim. 1989, 25, 2244.

6. Titanium Catalyzed Reactions
Ackermann, L.;Sandmann, R.; Kaspar L. T. Org. Lett. 2009, 11, 2031
Kulinkovich, O. G.; Sviridov, S. V.; Vasilevskii, D. A.; Pritytskaya, T. S. Zh. Org. Khim. 1989, 25, 2244.

7. Pyrroles
MacDiarmid, A. G. Angew. Chem. Int. Ed. 2001, 40, Estévez, V.; Villicampa, M.; Menéndez J. C. Chem.Soc.Rev., 2014, 43, Hantzsch, A. Chem. Ber. 1890, 23, Paal, C. Chem. Ber , Barton, D. H. R.; Zard S. Z. J.Chem. Soc. Chem. Comm. 1985, 10, 1098.

8. Tonks I. A.; Meier, J. C.; Bercaw J.E. Organometallics 2013, 32, 3451.
Background Work
Rothwell’s work : Titanacyclopentadiene and benzo[c]cinnoline to form pyrroles
Bercaw’s work : Pyrrole formation as by-products during alkyne hydroamination
Hill, J. E.; Fanwick, P. E.; Rothwell, I. P. Inorg. Chem , 1144.
Tonks I. A.; Meier, J. C.; Bercaw J.E. Organometallics 2013, 32, 3451.

9. Tonks I. A.; Meier, J. C.; Bercaw J.E. Organometallics 2013, 32, 3451.
Background Work
Tonks I. A.; Meier, J. C.; Bercaw J.E. Organometallics 2013, 32, 3451.

10. Preliminary Results and Optimization
Azobenzene can oxidize low valent Ti species
Hydroamination is competing with [2+2+1]
TiII intermediate must be involved due to the [2+2+2]

11. Preliminary Results and Optimization
Azobenzene can oxidize low valent Ti species
Hydroamination is competing with [2+2+1]
TiII intermediate must be involved due to the [2+2+2]

12. Preliminary Results and Optimization
Azobenzene can oxidize low valent Ti species
Hydroamination is competing with [2+2+1]
TiII intermediate must be involved due to the [2+2+2]

13. Preliminary Results and Optimization
Azobenzene can oxidize low valent Ti species
Hydroamination is competing with [2+2+1]
TiII intermediate must be involved due to the [2+2+2]
No hydroamination products observed
Both NPh units are incorporated in the product

14. Proposed Mechanism a

15. Mechanistic Investigation
TiII reoxidation to an imido TiIV might involve a disproportionation of an η2 -azobenzene
Crystal structure of 7 shows N-N bond length of Å
Thermolysis of 7 gives 1a and 0.5 eq. of azobenzene

16. Scope

17. Scope

18. Scope

19. Scope

20. Scope

21. Regioselectivity

22. Diazene Scope

23. Conclusions
Catalytic formation of polysubstituted pyrroles was achieved
New catalytic activity from a group 4 metal
Good yields for unhindered alkynes but poor selectivity
Lower yields for more hindered alkyne with better selectivity
Regioselectivity is substrate controlled
Weak substrate scope

25. Titanium Catalyzed Reactions
Kulinkovich, O. G.; Sviridov, S. V.; Vasilevskii, D. A.; Pritytskaya, T. S. Zh. Org. Khim. 1989, 25, 2244.