Skip to main navigationSkip to main content
The University of Southampton
Chemistry

Research project: Whitby: Insertion of carbenoids into zirconacycles

Currently Active: 
Yes

A wide range of carbenoids insert into 5 member zirconacycle to give ring expanded species...

Scheme 1
Click on image to expand

A wide range of carbenoids insert into 5 member zirconacycle to give ring expanded species – the first synthesis of zirconacyclohexanes and zirconacyclohexenes (scheme 1 ). [1]

Scheme 1. Formation of zirconacyclohexanes and zirconacyclohexenes.

Scheme 2
Click on image to expand

The functionalised zirconacyclohexanes and zirconacyclohexenes have a rich chemistry with great potential for developing efficient multi component construction methods for organic compounds which we are just beginning to explore. Two examples of the type of tandem reaction sequencies we have developed are shown in scheme 2. In each case an unusual rearrangement leads to novel structure types.[2]

Scheme 2. Tandem reaction sequencies using zirconacycles.

Scheme 3
Click on image to expand

For application to complex synthesis the regiochemistry of insertion of carbenoids needs to be predictable. We have established that insertions are almost always highly regioselective (Scheme 3)[3] but the reason for the contrasting regioselectivities observed is something we are still investigating by experimental and theoretical methods.

Scheme 3. Regioselectivity of insertion of carbenoids.

[1] Ring expansion of 5-to 6-member zirconacycles by carbenoid insertion, Dixon, S.; Fillery, S. M.; Kasatkin, A.; Norton, D.; Thomas, E.; Whitby, R. J. Tetrahedron 2004, 60, 1401-1416.

[2] A rearrangement to a zirconium-alkenylidene in the insertion of dihalocarbenoids and acetylides into zirconacycles, 1. Thomas, E.; Dixon, S.; Whitby, R. J. Angew. Chem. Int. Ed. 2006, 45, 7070-7072.

[3] The regiochemistry of zirconacycle elaboration, Thomas, E.; Dixon, S.; Whitby, R. J. Tetrahedron 2007, 63, 11686-11701. The regiochemistry of carbenoid insertion into zirconacycles, Gordon, G. J.; Luker, T.; Tuckett, M. W.; Whitby, R. J. Tetrahedron 2000, 56, 2113-2129.

nes.

Related research groups

Organic Chemistry: Synthesis, Catalysis and Flow
Share this research project Share this on Facebook Share this on Twitter Share this on Weibo
Privacy Settings