DAVIES Oxidizing Reagent

OAKIN Oxidation 84 DAKIN WEST Acylation 84 DANHEISER Annulation 85 DANISHEFSKY Sitytoxydenes 66 DARAPSKI Ammoacid synthesis 87 DARZENS-NENITZESCU Acylation 87 DAR2fENS Epoxide synthesis 88 DAVIDSON Oxazola synthesa 89 OELEPINEAMehydeoxidalion 89 DAVIS Oxidizing reagent 90 Decker 127... 

Another approach to the enantiomerically enriched sulfinimines reported by Davis and co-workers is the enantioselective oxidation of sulfenimines with an asymmetric oxidizing reagent, (-)-jV-(phenylsulfonyl)(3,3-dichlorocamphoryl)-... 

In the former case, almost complete stereoselective oxidation to the chiral selenoxides has been accomplished quite recently. The Davis oxidant, 3,3-di-chloro-l,7,7-trimethyl-2 -(phenylsulfonyl)spirobicyclol2.2.11heptane-2,3 -oxa-ziridine, was found to be the most efficient reagent for the enantioselective oxidation of a variety of prochiral alkyl aryl selenides [81. Asymmetric oxidation was accomplished by the treatment of the selenides with 1 molar equivalent of the Davis oxidant at 0°C to afford the corresponding chiral alkyl aryl selenoxides in quantitative yields with 91-95% ee (Scheme 1). The oxidation of methyl phenyl selenide was complete within 1 min, whereas that of triiso-propyl(a bulkier alkyl) phenyl selenide required a few hours. Typical results are... 

The synthesis of the 4 -spiroannulated ribonucleoside was aceomplished by elimination of the 2 -phenylthio group of compound 132 via a controlled oxidation with Davis oxaziridine reagent. 

Davis oxaziridine reagents such as 1 have exhibited ample synthetic utility as oxidizing agents for the hydroxylation of enolates to provide a-hydroxy carbonyl compounds, such as 2 with superb yield. When the oxaziridine is chiral and nonracemic, the hydroxylation has been shown to proceed with high stereoselectivity.1... 

DAKIN Oxidation 84 DAKIN - WEST Acylation 84 OANHEISER Annulation 85 DANISHEFSKY Silyloxydlenes 86 DARAPSKI Amtroaeid synthesis 87 DARZENS - NENITZESCU Acylation 87 DARZENS Epoxide synthesis 88 DAVIDSON Oxszole synthesis 89 DELEPINE Aldehyde oxidation 69 DAVIS Oxidzstg reagent 90 Decker 127... 

Epoxidation of 95 with Davis oxaziridine reagent [214,215], followed by NaBH4 reduction and DDQ oxidation affords 96, which upon deprotection by hydrogenolysis gives asperlicin 20 (15 steps from L-tryptophan with 8% overall yield). 

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