Development of the Julia asymmetric epoxidation reaction .2. Application of the oxidation to alkyl enones, enediones and unsaturated keto esters


Kroutil W., LASTERRASANCHEZ M., MADDRELL S., MAYON P., MORGAN P., ROBERTS S., ...More

JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1, no.23, pp.2837-2844, 1996 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Publication Date: 1996
  • Doi Number: 10.1039/p19960002837
  • Title of Journal : JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1
  • Page Numbers: pp.2837-2844

Abstract

Polyleucine-based systems have been used to catalyse the asymmetric oxidation of a variety of alkyl enones 1-4,9-14, an enynone 16 and a dienone 17 to afford the corresponding epoxides 5-8, 18-26 in good to excellent yield and optical purity. A range of enediones 30-32, 34 and one unsaturated keto ester 33 have also been epoxidised stereoselectively to afford optically active epoxides 35-39. The epoxidations were carried out with basic peroxide as the oxidant; the polyleucine catalyst was prepared from leucine N-carboxyanhydride using 1,3-diaminopropane, water (employing a humidity cabinet) or a polystyrene immobilised amine as the initiator. Preliminary mass spectral data on material derived from L-leucine and 1,3-diaminopropane (DAP-PLL) suggest that the catalyst consists of material that contains 22 +/- 10 leucine residues.