Formyl hydroperoxide

Simplest of the peroxyacids, peroxy linkage between a formyl group and hydrogen Synonyms performic acid formyl hydroperoxide permethanoic acid... 

Similar problems arise with quinolinium salts as both C2 and C4 are susceptible to radical addition. Where either of these positions is blocked by a substituent, reactions often proceed in high yield. For example, Minisci et al. have described a useful method of formylating heteroaromatic bases which begins with an iron(II) promoted reduction of /-butyl hydroperoxide <86JOC536>. The /-butyloxy radical thus produced abstracts a hydrogen atom from 1,3,5-trioxane 34 giving intermediate 33. Union of 33 and the quinolinium salt 35 next produces radical cation 36, which is oxidised to 32 by iron(III) (Scheme 14). 

Figure 3. OH radical-induced degradation of thymine. Oxidation involves either OH addition to the C5-06 double bond or OH-mediated hydrogen abstraction from the methyl group. Molecular oxygen then adds to the resulting carbon-centered radicals. This reaction yields hydroperoxide that further evolves into stable products, such as thymidine glycol (ThdGly), 5-hydroxymethyl-uracil (HMdUrd) and 5 formyl-uracil (5-FordUrd). N- represents the bond to the DNA backbone.

Reactions of Indoles. 2-Arylindoles react with tosyl azide under phase-transfer conditions to give 3-diazo-compounds (148). The phenylazoindole (149 R = N2Ph) is converted into the nitroindole (149 R = NO2) by ipso-nitration. Indoles are oxidized by thallium(III) nitrate to mixtures of oxindoles and isatins. Sensitized photo-oxygenation of the indole (150) yields the hydroperoxide (151), which forms compound (152) on treatment with methanolic potassium borohydride. Vilsmeier-Haack formylation of... 

Fig. 2.21. Successive models of the transition structures for Sharpless epoxidation (a) the hexacoordinate Ti core with hydroxide and hydroperoxide ligand and a coordinated alkene (b) Ti with methylhydroperoxide, allyl alcohol, and ethanediol as ligands (c) monomeric catalytic center incorporating f-butylhydroperoxide as oxidant (d) monomeric catalytic center with formyl groups added (e) representation of the active dimeric catalyst. Reproduced from J. Am. Chem. Soc., 117, 11327 (1995), by permission of the American Chemical Society.

Treatment of tertiary methylamines with Pt black at ambient temperature in O2 atmosphere yields an N-formyl secondary amide which may be hydrolyzed to the secondary amineN-Ethyl- and N-benzylamines ore not attacked. Tertiary amines and commercially available organic hydroperoxides give excellent yields of amine oxides in the presence of vanadium salts and other group VB and VIB metal... 

Photodecomposition of hydroperoxide (OOH) groups subsequently gives end-hydroxyl (OH) and end-formyl(aldehyde) (—C ) chains ... 

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