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Cyclopropanation aziridination

The Corey-Chaykovsky reaction entails the reaction of a sulfur ylide, either dimethylsulfoxonium methylide (1, Corey s ylide, sometimes known as DMSY) or dimethylsulfonium methylide (2), with electrophile 3 such as carbonyl, olefin, imine, or thiocarbonyl, to offer 4 as the corresponding epoxide, cyclopropane, aziridine, or thiirane. ... [Pg.2]

Carbene, nitrene, and oxo complexes of Mn-Cu represent challenging synthetic targets that would enable a better mechanistic understanding of metal-catalyzed cyclopropanation, aziridination, and oxidation reactions promoted by these complexes. By offering insights into the patterns of selectivity of these complexes, these studies may pave the way toward a rational design of a future generation of more efficient catalysts. [Pg.415]

Property Structural element Cyclopropane Aziridine Oxirane Cyclo butane... [Pg.66]

Keywords chalcone, benzylidene aniline, trimethyloxosulfonium iodide, ylide reaction, cyclopropane, aziridine... [Pg.70]

Reviews have featured epoxidation, cyclopropanation, aziridination, olefination, and rearrangement reactions of asymmetric ylides 66 non-phosphorus stabilized carbanions in alkene synthesis 67 phosphorus ylides and related compounds 68 the Wittig reaction 69,70 and [2,3]-Wittig rearrangement of a-phosphonylated sulfonium and ammonium ylides.71 Reactions of carbanions with electrophilic reagents, including alkylation and Wittig-Homer olefination reactions, have been discussed with reference to Hammett per correlations.72... [Pg.339]

Asymmetric ylide reactions such as epoxidation, cyclopropanation, aziridination, [2,3]-sigmatropic rearrangement and alkenation can be carried out with chiral ylide (reagent-controlled asymmetric induction) or a chiral C=X compound (substrate-controlled asymmetric epoxidations). Non-racemic epoxides are significant intermediates in the synthesis of, for instance, pharmaceuticals and agrochemicals. [Pg.142]

Aggarwal VK, Winn CL. Catalytic, asymmetric sulfur ylide-mediated epoxidation of carbonyl compounds scope, selectivity, and applications in synthesis. Acc. Chem. Res. 2004 37 611-620. Li A-H, Dai L-X, Aggarwal VK. Asymmetric ylide reactions epoxidation, cyclopropanation, aziridination, olefination, and rearrangement. Chem. Rev. 1997 97 2341-2372. [Pg.2137]

Tosylhydrazone salts could also be deconposed into the corresponding diazo compounds in the presence of a phase transfer catalyst. The addition of late transition metal complexes leads to the formation of metal carbenoid species which undergo various reactions such as cyclopropanation, aziridination, epoxidation, and C-H insertion. While both cyclopropanation and aziridination work equally well in the presence of the sodium and lithium tosylhydrazone salts, it was established that the sodium salt provided higher yields and selectivities in the reaction with aldehydes which led to the formation of epoxides (eq 28). ... [Pg.432]

Apart from cyclopropenation, catalytic aziridination with nitrene transfer to olefins is generally considered an analogue reaction of metal-catalyzed carbene-transferred cyclopropanation. Aziridination and cyclopropanation are proposed to share fundamental mechanistic features. Many of the catalysts that were successfully applied in aziridination are also efficient catalysts for cyclopropanation. For... [Pg.898]

The abstract of the terminal proton of the epoxide unit followed by the coordination of lithium metal in the intermediate 455 promoted intramolecular cyclopropanation. Aziridines also underwent a similar conversion to give aminocyclopentanes fused with cyclopropane... [Pg.58]

Li A-H, Dai L-X, Aggarwal VK. Asymmetric ylide Reactions epoxidation, cyclopropanation, aziridination, olefination, and rearrangement. Chem. Rev. 1997 97(6) 2341-2372. [Pg.496]

Recently, extensive efforts have been devoted to the synthesis of cycHc peroxides since the discovery of artemisinin and related antimalarial l,2,4-trioxanes. > As described previously, PET oxygenation is a unique but effective method for the preparion of cycHc peroxides, which is also appHcable to the synthesis of the peroxide structures from arylated cyclopropanes, aziridines, and olefins. - ... [Pg.1050]


See other pages where Cyclopropanation aziridination is mentioned: [Pg.640]    [Pg.181]    [Pg.640]    [Pg.246]    [Pg.391]    [Pg.391]    [Pg.94]    [Pg.2]    [Pg.178]    [Pg.391]    [Pg.565]    [Pg.681]    [Pg.686]    [Pg.70]    [Pg.536]    [Pg.2920]    [Pg.470]   
See also in sourсe #XX -- [ Pg.292 ]




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Cyclopropanation, Epoxidation, and Aziridination of Alkenes (Cu, Rh, Mn, Ti)

Cyclopropane aziridine

Cyclopropane aziridine

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