PLATINUM-CATALYZED OXIDATIONS WITH HYDROGEN-PEROXIDE - ENANTIOSPECIFIC BAEYER-VILLIGER OXIDATION OF CYCLIC-KETONES

Citation
A. Gusso et al., PLATINUM-CATALYZED OXIDATIONS WITH HYDROGEN-PEROXIDE - ENANTIOSPECIFIC BAEYER-VILLIGER OXIDATION OF CYCLIC-KETONES, Organometallics, 13(9), 1994, pp. 3442-3451
Citations number
52
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry Inorganic & Nuclear","Chemistry Inorganic & Nuclear
Journal title
ISSN journal
0276-7333
Volume
13
Issue
9
Year of publication
1994
Pages
3442 - 3451
Database
ISI
SICI code
0276-7333(1994)13:9<3442:POWH-E>2.0.ZU;2-B
Abstract
The Baeyer-Villiger oxidation of some cyclic ketones as a potential en try to naturally occurring lactones is reported in the presence of a v ariety of platinum(II) complexes as catalysts. The reaction is accompl ished using hydrogen peroxide as oxidant and is tested in a discontinu ous and semicontinuous fashion. The stereochemistry of the catalyzed t ransformation has been determined, and it is found that the reaction p roceeds with retention of configuration at the migrating carbon atom. Chiral catalysts of the type [(P-P)Pt(CF3)(solv)](+) and (P-P*)Pt(2-v an) (P-P = various chiral diphosphines; 2-van = the dianion of 2-vani llin) have been synthesized and characterized. While the mechanism of action of the former complexes is already known, the latter require 1 equiv of HClO4 to become catalytically active. This reaction has been investigated synthetically and spectroscopically by P-31{H-1} NMR and IR and results in the formation of a new cationic Pt-carbonyl species. The asymmetric Baeyer-Villiger oxidation of a variety of racemic mixt ures of chiral ketones results in a kinetic resolution leading to chir al lactones with ee up to 58%.