Ozone with allyl acetate

In the late fifties Regie Nationale des Usines Renault (86) described the preparation of allyl ethers through reaction of alkali cellulose with allyl halides in carbon tetrachloride or benzene. With products having degrees of substitution between 0.2 to 0.8 graft copolymerization could be achieved when activated by pretreatment with air or ozone or by initiation with peroxide catalysts with styrene, acrylonitrile, vinyl acetate, or acrylates. 

Lee S-H, Mendenhall GD (1988) Relative yields of excited ketones from self-reactions of alkoxyl and alkylperoxyl radical pairs. J Am Chem Soc 110 4318-4323 Leitzke A, Reisz E, Flyunt R, von Sonntag C (2001) The reaction of ozone with cinnamic acids - formation and decay of 2-hydroperoxy-2-hydroxy-acetic acid. J Chem Soc Perkin Trans 2 793-797 Lodhi ZH, Walker RW (1991) Oxidation of allyl radicals kinetic parameters for the reactions of allyl radicals with H02 and 02 between 400 and 480 °C. J Chem Soc Faraday Trans 87 2361-2365 Martini M, Termini J (1997) Peroxy radical oxidation of thymidine. Chem Res Toxicol 10 234-241... 

The rate constants for oxidation of a series of cycloalkenes with ozone have been determined using a relative rate method. The effect of methyl substitution on the oxidation of cycloalkenes and formation of secondary organic aerosols has been analysed.155 Butadiene, styrene, cyclohexene, allyl acetate, methyl methacrylate, and allyl alcohol were epoxidized in a gas-phase reaction with ozone in the absence of a catalyst. With the exception of allyl alcohol, the yield of the corresponding epoxide ranged from 88 to 97%.156 Kinetic control of distereoselection in ozonolytic lactonization has been (g) reported in the reaction of prochiral alkenes.157... 

A combination of rtiodium(III) chloride with silver acetate, and treatment of rhodium(II) acetate in acetic acid solution with ozone, are two methods for generation of the (is-oxotrimetal-acetato complex of rhodium [Rhs0(0Ac)6 2O)3]0Ac. This RhsO complex was found to effect catalytic allylic oxidation of alkenes efficiently to give the corresponding a -unsaturated carbonyl compounds in the presence of a reoxidant such as r-butyl hydroperoxide, although in disappointing yield (equation 44). 

The second synthetic approach to oidiolactone C (61) is summarized in Scheme 20. This route also commences with the ozonolysis of trans-communic acid 180. Now, when this compound was exposed to ozone in excess, keto aldehyde 187 was obtained in 76% yield. The key step in this approach was the y-lactone closure via chemoselective reduction of the lactone moiety on compound 189 through a SN2 mechanism. Compound 189 could be prepared by saponification of the corresponding methyl ester with sodium propanethiolate. Once the primary alcohol is oxidized, the completion of the synthesis of key lactone 103 only requires the allylic oxidation of the C-17 methyl with concomitant closure of the 8-lactone. This conversion was achieved with Se02 in refluxing acetic acid to give 103 in 51% yield. 

Reaction of allylic alcohol 396 with paraformaldehyde using a catalytic amount of p-toluenesulfonic acid gave cyclic carbamate 397, which upon reduction with lithium aluminum hydride afforded aminodiol 398. Oxidative cleavage of the double bond of 398, achieved by dry silica gel ozonization (80JA5968) of the trifluoro acetate salt of aminodiol 398, gave ( )-5-epi-desosamine (399) (Scheme 49). 

ALLYL PHENYL ETHER (1746-13-0) C ipO Combustible liquid (flash point 143°F/62°C). May form peroxides on contact with air. Violent reaction may occur with strong oxidizers, strong acids acetyl peroxide boron trifluoride aluminum hydride (possible explosion). Incompatible with nitrosyl perchlorate, ozone (may form explosive ethyl peroxide, aldehyde and acetic acid). On small fires, use dry chemical powder (such as Purple-K-Powder), foam, or CO2 extinguishers. 

Ozonolysis of unsaturated hydroperoxy acetal 226, readily obtained by trapping carbonyl oxides with primary unsaturated allylic or homoallylic alcohols <1997J(P1)5>, with ozone in methanol/ether at —78°G gave the 6-hydroxy-l,2,4-trioxane derivatives 227 almost quantitatively and as a single isomer (structure confirmed by 1-D NOE spectroscopy see Scheme 64) <1997JOC4949>. In the case of substitution (R R = H, Me or Me, Me), a mixture of two and three isomers, respectively, were obtained, all completely assigned by H NMR spectroscopy <1997JOC4949>. 

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