63704-22-3

Upstream product

• 40237-72-7 (2-methoxyethene-1,1-diyl)dibenzene 
• 67-56-1 methanol 
• 908093-98-1 diazodiphenylmethane 
• 5457-37-4 methoxy-2 triphenyl-1,2,2 ethanone-1 

Relevant academic research and scientific papers

Cyclic mechanism in the trapping of carbonyl oxides with alcohols and carboxylic acids

The reaction of diphenylcarbonyl oxide with alcohols and carboxylic acids, which has been classified as a nucleophilic trapping, is shown to be in the reactivity order: AcOH?MeOHCF3CH2OHEtOH?t-BuOH. A laser-flash spectroscopy indicated that the reaction of carboxylic acids is very fast, that is, one-tenth of the diffusion rate. These results suggest that the hydroxyl compounds react as an acid and a nucleophile at the same time and the major reaction is via the seven- and five-membered cyclic mechanism for RCO2H and ROH, respectively.

Ozonolysis of Vinyl Ethers in Solution and on Polyethylene

Ozonolyses of the vinyl ethers 1a-f in methanol afforded almost exclusively the corresponding α-methoxy hydroperoxides 4, suggesting the preferred formation of the carbonyl oxides 2.In aprotic solvents including methyl formate, the predominant modes of decay of the carbonyl oxides 2 were cyclodimerization, reduction, and rearrangement, yet no ozonide formation.By contrast, ozonolyses of 1a-f on polyethylene gave the α-methoxy-substituted ozonides 14 in fair yields.Ozonolyzes of 1a-f in the presence of added carbonyl compounds 6 in methylene chloride or ether yielded the corresponding cross ozonides.Judged from the ozonide yields, the reactivities of the carbonyl compounds follow the sequence: (ClCH2)2C=O > ClCH2COCH3 > (CH3)2C=O and 2-CF3C6H4CHO > PhCHO.

Reactivity of Carbonyl Oxides. Characteristic Nucleophilic Oxygen Atom Transfer from R2COO beside Electrophilic and Radical Reactions

According to a MINDO/3 calculation, carbonyl oxide H2COO has a large contribution of zwitterionic structure 1a, which is not altered by phenyl substituent.The dye-sensitized photooxidation of diazomethanes in CH2Cl2 - MeOH afforded ca. 30percent yield of α-methoxy hydroperoxides as product from 1a and MeOH.Relative reactivities of various types of substrates toward the carbonyl oxide from diazofluorene and 1O2 have been determined.While benzene gave phenol in a low yield, substituted benzenes such as toluene or anisole yielded products by hydrogen atom abstraction on the side chain as a major reaction.Olefins gave a rather minor amount of epoxides; the predominant reaction was C-C cleavage or allylic hydrogen abstraction.The realtive reactivity with carbonyl oxide is in the order Ph2SO >> Ph2S > C = C > benzene, where C = C means α-methylstyrene.This order is in sharp contrast to the case of peroxy acid, Ph2S >> Ph2SO >> C = C, or to the order with acylperoxy radical, C = C >> Ph2S, Ph2SO.The above order with carbonyl oxide indicates a nucleophilic oxygen atom transfer as a characteristic reaction; this was clearly shown by the positive ρ value of +0.26 for substituted diphenyl sulfoxides.The reactivities of various substrates revealed that another characteristic reaction is hydrogen atom abstraction as a radical, and carbonyl oxides could be regarded as a rather poor electrophilic O-transfer agent.These features may be understood by representing carbonyl oxides as a resonance hybrid of R2C=O+-O- (1a) and R2C*-O-O* (1c).

Photoepoxidation of Olefins with Benzoins and Oxygen. Epoxidation with Acylperoxy Radical

Benzoin was photooxidized to yield benzaldehyde, peroxybenzoic acid, and hydrogen peroxide.The addition of styrenes to this photooxidation system afforded high yields of epoxides together with some C-C cleaved products.While the C-C cleavage products increased with increasing concentration of olefins, the epoxide yield was constant and nearly quantitative; the stoichiometry at the infinite olefin concentration was such that 1 mol of benzoin produces 1 mol of epoxide and 2 equiv of C-C cleaved product.The effect of olefin concentration is analyzed to show that the C-C cleavage is ascribed to benzoyloxy and α-hydroperoxy radicals, PhCH(OH)OO..The photoepoxidation proceeds by a way of acylperoxy radical, affording predominantly trans-epoxide (e.g., 100percent trans-epoxide from stilbenes and 77percent trans-epoxide from 2-octenes).The relative reactivities of olefins differ significantly from those with molecular peroxyacid; the additivity of methyl substitution does not hold, and aliphatic olefins are less reactive than the corresponding aromatic ones.The relative reactivities of photoepoxidation are examined on the basis of the stability of a resulting adduct radical between the acylperoxy radical and olefin.The peroxy radical is not reactive toward pyridine or sulfoxides.The photoepoxidation with benzoin ethers proceeds similarly except the formation of esters, which is explained by the β-scission or the 1,2-phenyl migration of intermediary α-alkoxy radical.These results are discussed in relation to practical photopolymerizations and to an origin of photoxic substances.