40825-12-5Relevant academic research and scientific papers
Formation and synthetic use of oxygen-centred radicals with (diacetoxyiodo)arenes
Togo, Hideo,Muraki, Takahito,Hoshina, Yoichiro,Yamaguchi, Kentaro,Yokoyama, Masataka
, p. 787 - 793 (2007/10/03)
o-Alkyl- or o-aryl-benzenecarboxylic acids and alcohols containing an aromatic ring are treated with a (diacetoxyiodo)arene-iodine system to give the corresponding cyclized products such as phthalide, benzocoumarin and chromane derivatives in moderate to good yields via the corresponding oxygen-centred radicals. For the carboxylic acids, [bis(trifluoroacetoxy)iodo]benzene functions effectively, while (diacetoxyiodo)benzene is effective for the alcohols. Chromane and its derivatives are obtained as iodinated compounds by hypoiodite species derived from (diacetoxyiodo)benzene and iodine. Copyright 1997 by the Royal Society of Chemistry.
Reactions of Carbonyl Compounds in Basic Solutions. Part 12. The Mechanism of the Alkaline Hydrolysis of 3-Substituted Phenyl 2-Acetyl- and 2-Benzoylbenzoates
Anvia, Fredrick,Bowden, Keith
, p. 1805 - 1807 (2007/10/02)
Rate coefficients have been measured for the alkaline hydrolysis of 3-substituted phenyl 2-acetyl- and 2-benzoyl-benzoates in 70percent (v/v) dioxane-water at several temperatures.The enthalpies and entropies of activation have been evaluated.The effects of substitution have been assessed by means of the Hammett equation.Comparison of the reaction constants with those for model systems, as well as the relative rates and activation parameters, indicate that the rate-determining step for the 2-acetyl esters is attack by hydroxide anion at the keto-carbonyl group and for the2-benzoyl esters it is the intramolecular attack on the ester-carbonyl group, which follows equilibrium addition of the hydroxide anion at the keto-carbonyl group.
SYNTHESIS OF STABLE 3,6-EPIDIOXYPYRAZIN-2-ONES AND α-OXO IMIDES BY PHOTOOXYGENATION OF PYRAZIN-2-ONES WITH SINGLET OXYGEN
Nishio, Takehiko,Tokunaga, Naoko (nee Nakajima),Kondo, Masaji,Omote, Yoshimori
, p. 2921 - 2926 (2007/10/02)
Irradiation of the pyrazin-2-ones (1) in methanol under oxygen gave the 3,6-epidioxypyrazin-2-ones (2), the N-alkyl-N-acyl-α-oxo-amides (3), and the unusual products, N-alkyl-α-acyloxy-α-methoxy amides (4).The mechanism for the formation of these photoproducts is discussed.Furthermore, thermal or photochemical treatment of the 3,6-epidioxypyrazinones (2), which could be readily obtained by the reaction of (1) and singlet oxygen, gave the N-alkyl-N-acyl-α-oxo amides (3) and this reaction would provide a useful synthetic method for the α-oxo imides (3).
Stereoisomeric 1,2,4,6,7,9-Hexaoxecan Derivatives from Dimerisation of a 1,2,4--Trioxolan; Stereospecific Interconversion
Rio, Guy,Rio, Marie-Jeanne
, p. 72 - 74 (2007/10/02)
Carbon disulphide and other acceptors catalyse the dimerisation of the endoperoxide formed from photooxygenation of 1,3-diphenylisobenzofuran to mixtures of four stereoisomeric diperoxides; pairs of these dimers are stereospecifically interconvertible on gentle heating.
Chemiluminescence of Organic Peroxides. Thermal Generation of an o-Xylylene Peroxide
Smith, Jimmie P.,Schrock, Alan K.,Schuster, Gary B.
, p. 1041 - 1047 (2007/10/02)
Thermolysis of 1,4-diphenyl-1,4-dioxa-2,3-benzopyrone (endoperoxide 1) in p-xylene solution generates chemiluminescence.Three products are formed from thermolysis of 1.The major product, trapped in 70percent yield by added maleic anhydride, is 1,4-diphenyl-2,3-benzodioxin (o-xylene peroxide 7).This peroxide eventually becomes o-dibenzoylbenzene 3 which is isolated from the reaction in 85percent yield.The two other products, 1,3-diphenylisobenzofuran (6) and phenyl o-benzoylbenzoate (4), are isolated in yields of ca. 2percent and 5percent, respectively.The observed chemiluminescence results from interaction of 7 with an added fluorescent activator or with the product 1,3-diphenylisobenzofuran according to the chemically initiated electron-exchange luminescence (CIEEL) mechanism.
