Monatshefte für Chemie / Chemical Monthly

, Volume 115, Issue 10, pp 1237–1254

Enantioselektive Cyclopropanierung von 1,1-Diphenylethylen und Diazoessigester mit Kupfer-Katalysatoren

Asymmetrische Katalysen, 21. Mitt.
  • Henri Brunner
  • Wolfgang Miehling
Organische Chemie Und Biochemie

DOI: 10.1007/BF00809355

Cite this article as:
Brunner, H. & Miehling, W. Monatsh Chem (1984) 115: 1237. doi:10.1007/BF00809355

Enantioselective cyclopropanation of 1,1-diphenylethylene and diazoacetic acid ester with copper catalysts

Abstract

Copper(II) compounds catalyze the reaction of 1,1-diphenylethylene with diazoacetic acid ethylester. The main product is 2,2-diphenylcyclopropane carboxylic acid ethylester. The formation of the carbene dimerization products fumaric and maleic acid diethylester can be suppressed by the continuous addition of diazoacetic acid ester to 1,1-diphenylethylene.

37 optically active ligands, partly new, were combined with copper(II)-acetate to givein-situ-catalysts. In five cases isolated copper complexes were used as catalysts. The best optical inductions in the formation of 2,2-diphenylcyclopro-pane carboxylic acid ethylester with up to 65.6% ee were achieved withSchiff base ligands, which derive from salicylaldehyde and amino alcohols, obtained from amino acid esters and phenylGrignard.

Keywords

Catalytic enantioselective cyclopropanationCopper (II) catalystsOptical induction

Copyright information

© Springer-Verlag 1984

Authors and Affiliations

  • Henri Brunner
    • 1
  • Wolfgang Miehling
    • 1
  1. 1.Institut für Anorganische ChemieUniversität RegensburgRegensburgBundesrepublik Deutschland