Epoxide compounds syntheses

Scheme 9.14 Epoxidation of aliphatic alkenes and applications in bioactive compound synthesis.

Commerqon et al.40 developed a method based on an Evans-type auxiliary-controlled aldol reaction. Subsequent treatment of the aldol product with base produced the standard epoxide compound for the asymmetric synthesis of the taxol side chain (Scheme 7-84). 

Alkyl hydroperoxides, including ethyl hydroperoxide, cuminyl hydroperoxide, and tert-butyl hydroperoxide, are not used by V-BrPO to catalyze bromination reactions [29], These alkyl hydroperoxides have the thermodynamic driving force to oxidize bromide however, they are kinetically slow. Several examples of vanadium(V) alkyl peroxide complexes have been well characterized [63], including [V(v)0(OOR)(oxo-2-oxidophenyl) salicylidenaminato] (R = i-Bu, CMe2Ph), which has been used in the selective oxidation of olefins to epoxides. The synthesis of these compounds seems to require elevated temperatures, and their oxidation under catalytic conditions has not been reported. We have found that alkyl hydroperoxides do not coordinate to vanadate in aqueous solution at neutral pH, conditions under which dihydrogen peroxide readily coordinates to vanadate and vanadium( V) complexes (de la Rosa and Butler, unpublished observations). Thus, the lack of bromoperoxidase reactivity with the alkyl hydroperoxides may arise from slow binding of the alkyl hydroperoxides to V-BrPO. 

Karpf, M. et al. New, Azide-Free Transformation of Epoxides into 1,2-Diamino Compounds Synthesis of the Anti-Influenza Neuraminidase Inhibitor Oseltamivir Phosphate (Tamiflu). 3.4.4 2001 [135]... 

The partially epoxidized compound was shown to have an average of two epoxy groups per cube. Both polyepoxides readily polymerized in the presence of Lewis acid catalysts or in reaction with amines. This suggested their potential as coupling agents in the synthesis of novel inorganic-organic hybrids. 

Obtained ohlorohydrines serve as raw material for synthesis of corresponding epoxide compounds according to the known methods the yields achieve 85-90. ... 

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