Atomic oxygen. III. Reaction of 1,3-butadiene with oxygen (3P) atoms

Abstract

of a dipolar transition state8 consisting of diphenoquinone and benzene in place of 4 cannot be ruled out at present.

Chloroperoxidase-mediated oxidation of 1,3-butadiene to 3-butenal, a crotonaldehyde precursor

“…Further evidence for the identity of the new peak was obtained by GC-MS (Figure 3); the fragmentation pattern of the 3-buteanl peak obtained from 1,3-butadiene incubations was similar to that obtained with the reference material obtained by the oxidation of 3-buten-l-ol by either CrOs or chloroperoxidase-H202. These spectra also match the fragmentation pattern listed in the literature for 3-butenal (25). Furthermore, 3-butenal, BM, and CA were not detected when either chloroperoxidase or H2O2 was omitted from the incubation mixture (Figure 2).…”

“…The formation of both 3-butenal and CA and the inability to detect the formation of methyl vinyl ketone (retention time 2.25 min) under the various incubation conditions provide further support to the hypothesis that 1.3-butadiene oxidation occurs predominantly by an oxygen transfer to a terminal carbon rather than to a central carbon of 1,3-butadiene, which would have resulted in the detection of both BM and methyl vinyl ketone. Whereas these results are consistent with the chemical reaction of atomic oxygen in its ground (triplet) state with 1.3-butadiene (25), the exact mechanism of the oxygentransfer reaction and the source of the oxygen in the chloroperoxidase-catalyzed reactions remain to be established.…”

“…(Milwaukee, WI). spectrophotometrically by monitoring the formation of dichlorodimedon from monochlorodimedon and H2O2 at 278 nm at 25 °C (6,22), was found to be nearly 80% of the activity reported by Sigma; chloroperoxidase units were not corrected. All other chemicals were of the highest grade commercially available.…”

Chiral nuclear magnetic resonance solvating agents. Resolution, determination of enantiomeric purity, and assignment of absolute configuration of cyclic and acyclic sulfinate esters

“…Larger alkoxyl substituents give greater nonequivalence magnitudes of predictable senses. (11) The evidence for inversion at sulfur in the reactions of nucleophiles, especially Grignard reagents, Is well established. Our analogy (upon which our argument for inversion in the case of sultines is based) is occasioned by the structural similarity of sultines to acyclic sulfinates and supported by our observation that the reaction of Grignard reagents with sultines (as in the case for sulfinates) is stereospecific, the enantiomeric purity of the sulfoxide alcohol product being identical, allowing for experimental error, to that of the starting sultine.…”

Atomic oxygen. V. Reactions of enol ethers with oxygen (3P) atoms

“…For example, 3-butenal is produced by reaction of 1,3-butadiene with oxygen (3P) atoms. 4 Ground state (3P) oxygen atoms react with olefins of formula CnH2n to produce epoxides, aldehydes, and ketones of formula CrlH2"0. Cvetanovic6 has proposed that 0(3P) atoms add to olefins to form short-lived carbon-oxygen 1,3-biradicals.…”