Soluble polyisobutylene-supported reusable catalysts for olefin cyclopropanation Academic Article

abstract

• Polyisobutylene oligomers (PIB) have been used as soluble supports for the immobilization of cyclopropanation catalysts. In addition to simple carboxylate ligands, chiral bisoxazolines have been successfully attached to these heptane-soluble polymers. Their use and recovery has been investigated using cyclopropanation of styrene as an example. An achiral PIB-bound Rh(II) catalyst showed good activity and could be easily recycled nine times using a liquid-liquid biphasic separation technique. PIB-supported bisoxazoline ligands for Cu(I) catalysts were also prepared. These chiral catalysts showed good catalytic activity and stereoselectivity. A chiral ligand prepared from phenylglycine provided the most effective stereocontrol and gave the trans- and cis-cyclopropanation products in 94% ee and 68% ee, respectively. All three PIB-bound chiral bisoxazoline-Cu(I) catalysts prepared could be reused five to six times. 2007 Elsevier Ltd. All rights reserved.

authors

• Bergbreiter, David

published proceedings

• TETRAHEDRON LETTERS

author list (cited authors)

• Bergbreiter, D. E., & Tian, J.

citation count

• 32

complete list of authors

• Bergbreiter, David E||Tian, Jianhua

publication date

• June 2007

publisher

• Elsevier  Publisher

published in

• Tetrahedron Letters  Journal

keywords

• Bisoxazoline
• Cyclopropanation
• Polyisobutylene
• Polymer Supports

Digital Object Identifier (DOI)

• 10.1016/j.tetlet.2007.04.147

start page

• 4499

end page

• 4503

volume

• 48

issue

• 26

URL

• http%3A%2F%2Fdx.doi.org%2F10.1016%2Fj.tetlet.2007.04.147