A renewable tertiary hydroperoxide has been efficiently synthesized in 83% overall yield starting from commercially available (+)-endo-2-norborneol. This oxygen donor, derived from (+)-norcamphor, when employed in Ti(O i-Pr)(4)-catalyzed sulfoxidations, proved to be considerably more reactive when compared to a previously reported camphor-derived hydroperoxide. Reduced steric hindrance of the new oxidant lowered the level of asymmetric induction achieved in the oxidation, but stereo-convergent kinetic resolution has been exploited to improve enantioselectivity. Excellent recovery (95%) of the tertiary alcohol at the end of the sulfoxidation provides a highly advantageous chiral resource saving protocol.
Titolo: | Synyhesis of a renewable hydroperoxide from (+)-norcamphor:implications of steric modification of the bicyclic framework on asymmetric sulfoxidation | |
Autori: | ||
Data di pubblicazione: | 2004 | |
Rivista: | ||
Abstract: | A renewable tertiary hydroperoxide has been efficiently synthesized in 83% overall yield starting from commercially available (+)-endo-2-norborneol. This oxygen donor, derived from (+)-norcamphor, when employed in Ti(O i-Pr)(4)-catalyzed sulfoxidations, proved to be considerably more reactive when compared to a previously reported camphor-derived hydroperoxide. Reduced steric hindrance of the new oxidant lowered the level of asymmetric induction achieved in the oxidation, but stereo-convergent kinetic resolution has been exploited to improve enantioselectivity. Excellent recovery (95%) of the tertiary alcohol at the end of the sulfoxidation provides a highly advantageous chiral resource saving protocol. | |
Handle: | http://hdl.handle.net/11386/1058689 | |
Appare nelle tipologie: | 1.1.2 Articolo su rivista con ISSN |