The review focuses on our results concerning the synthesis of functionalized and simple furyl hydroperoxides and their employment as oxygen donors in metal-catalysed asymmetric oxidations. The first part describes the synthetic approaches (chemical, photochemical, enzymatic) to furyl hydroperoxides as racemic and enantiopure compounds. The second part covers their employment in Sharpless modified procedure for the epoxidation of allylic alcohols, oxidation of prochiral sulfides and kinetic resolution of racemic sulfoxides. Furyl hydroperoxides have been used as oxidants using catalytic Ti(Oi-Pr)(4)/(R)-BINOL system for the asymmetric sulfoxidation and when using enantiomerically enriched BINOL, non linear positive effects ((+)-NLE) have been observed. Finally, the first results as stereoselective oxidants in absence of chiral ligands have been reported in the epoxidation of allylic alcohols. Discussion includes highlighting of efficiency and performance of these oxidants as alternative reagents to commercial t-butyl hydroperoxide (TBHP) and cumyl hydroperoxide (CHP).
Synthesis and use of furyl hydroperoxides as reagents in asymmetric oxidations
LATTANZI, Alessandra;SCETTRI, Arrigo
2004-01-01
Abstract
The review focuses on our results concerning the synthesis of functionalized and simple furyl hydroperoxides and their employment as oxygen donors in metal-catalysed asymmetric oxidations. The first part describes the synthetic approaches (chemical, photochemical, enzymatic) to furyl hydroperoxides as racemic and enantiopure compounds. The second part covers their employment in Sharpless modified procedure for the epoxidation of allylic alcohols, oxidation of prochiral sulfides and kinetic resolution of racemic sulfoxides. Furyl hydroperoxides have been used as oxidants using catalytic Ti(Oi-Pr)(4)/(R)-BINOL system for the asymmetric sulfoxidation and when using enantiomerically enriched BINOL, non linear positive effects ((+)-NLE) have been observed. Finally, the first results as stereoselective oxidants in absence of chiral ligands have been reported in the epoxidation of allylic alcohols. Discussion includes highlighting of efficiency and performance of these oxidants as alternative reagents to commercial t-butyl hydroperoxide (TBHP) and cumyl hydroperoxide (CHP).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.