Advances in the chemistry of oxaziridines.
View Article:
PubMed Central - PubMed
Affiliation: Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States.
reagents; oxidations and aminations of alkanes, alkenes, arenes, amines, identity of their N-substituent, which exerts a significant effect on their reactivity... and acid, only the tert-butyldiphenylsilyl (TBDPS) derivative has been successfully synthesized... in oxygen transfer reactions to alkenes... tend to be more powerful oxygen atom-transfer reagents, these positively asymmetric epoxidation reactions with moderate to excellent enantioselectivities the α-alcohol after ring-opening of the epoxide... Directed reduction for decomposition of the oxaziridine... Thus, one-electron reduction invoked in Scheme 28... The greater reactivity oxygen atom transfer reactions continues to be the most broadly appreciated |
![]() Related In:
Results -
Collection
License getmorefigures.php?uid=PMC4150611&req=5
fig2: Asynchronoustransition state for oxygen atom transfer reactionsof N-sulfonyloxaziridines. Mentions: At elevatedtemperatures, Davis’ oxaziridines can be utilized to synthesizeepoxides from alkenes.64 Experimentally,the transition state for the transfer of oxygen from N-sulfonyloxaziridines to alkenes has been investigated using theendocyclic restriction test.65 By evaluatinga number of substrates containing an oxaziridine and an alkene, Beakand co-workers concluded that the transition state of oxygen transferfrom an N-sulfonyloxaziridine to a correspondingnucleophile is one in which N–O bond cleavage is more advancedthan C–O bond cleavage (Figure 2, 47). Houk et al. also performed computational studies thatprobe the transfer of oxygen from oxaziridines to alkenes. These calculationssimilarly indicate a concerted, asynchronous process; advanced cleavageof the N–O bond is accompanied by significant buildup of partialnegative charge at nitrogen.66 Thus, toa first approximation, oxaziridines can be considered electrophilicoxidants, and factors that stabilize the incipient negative chargeat nitrogen are expected to increase the reactivity of oxaziridines. |
View Article: PubMed Central - PubMed
Affiliation: Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States.
reagents; oxidations and aminations of alkanes, alkenes, arenes, amines, identity of their N-substituent, which exerts a significant effect on their reactivity... and acid, only the tert-butyldiphenylsilyl (TBDPS) derivative has been successfully synthesized... in oxygen transfer reactions to alkenes... tend to be more powerful oxygen atom-transfer reagents, these positively asymmetric epoxidation reactions with moderate to excellent enantioselectivities the α-alcohol after ring-opening of the epoxide... Directed reduction for decomposition of the oxaziridine... Thus, one-electron reduction invoked in Scheme 28... The greater reactivity oxygen atom transfer reactions continues to be the most broadly appreciated