MAIN GROUP ORGANOMETALLIC CHEMISTRY

The group has been working for many years in the area of main group organometallic chemistry and this work continues with the objective of providing useful synthetic methodologies for the organic chemist and greater insight into the nature of the reagents involved. The activities may be classified as follows:

Reductive Metalation
Reductive cleavage of phenyl thioethers by lithium, usually in the presence of an electron transfer reagent such as naphthalene, has developed into a useful synthetic procedure for the preparation of organolithium reagents. Current interests of the group centre on applying this procedure to previously unexamined compounds or, by suitable modification of the reaction conditions (the solvent for example) to make this route viable for previously problematic substrates.

Recent Publications
C.G. Screttas, G.A. Heropoulos, M. Micha-Screttas, B.R. Steele, D.P. Catsoulacos, Tetrahedron Lett., 2003, 44, 5633-5635
C.G. Screttas, G.A. Heropoulos, M. Micha-Screttas, B.R. Steele, Tetrahedron Lett. 2005, 46, 4357-4360

Modified Organometallic Reagents
The use of additives to modify the reactivity of organometallic reagents such as organolithiums is well-established. Recent work of our group has involved the use of alkali metal dimethylaminoethoxides to enhance the basic strength of organolithium reagents and to promote addition reactions with olefins (see here for more details). The effects of addition of magnesium alkoxides can also cause subtle variations in selectivity.

Recent Publications
C.G. Screttas, B.R. Steele, Appl. Organomet. Chem. 2000, 14, 653-659
B.R. Steele, C.G. Screttas, J. Am. Chem. Soc. 2000, 122, 2391-2392

NMR studies on organometallic reagents
Multinuclear NMR studies provide  kinetics and equilibrium information for reactions of organometallic reagents as well as structural insights on the nature of the reactive species in solution. Studies involving 31-P, 6/7-Li as well as 13-C and 1-H are carried out both on diamagnetic species and the paramagnetic alkali metal aromatic radical ions.

Recent Publications
M. Micha-Screttas, G. A. Heropoulos, B.R. Steele, Mag. Res. Chem. 2001, 39, 586-592
M. Micha-Screttas, C.G. Screttas, B.R. Steele, G. A. Heropoulos, Tetrahedron Lett. 2002, 43, 4871-4873