The synergistic antioxidant effect of tocopherol (Toc) and monoacylglyceryl citrate, malate, and succinate in lard and palm oil was investigated by the oven test at 60°C and the AOM test. The antioxidant effect of these esters was also studied. 1) The results of the oven test indicated that monoacylglyceryl citrate (MGC) showed little antioxidant effect in the lard, while no effect was observed in the palm oil. 2) In the oven test, it was indicated that MGC controlled an increase of POV in the initial stage of the induction period of lard added Toc of 0.01% or less, and contributed to further increase in the antioxidant effect of Toc. Hewever, the effect was reduced by adding MGC together with Toc of 0.02% or more. On the other hand, Toc in the palm oil was not affected by the addition of MGC. 3) In the case of the AOM test, MGC was useless for improvement of the antioxidant effect of Toc. 4) Monoacylglyceryl malate and succinate in the lard showed little antioxidant effect, and also indicated increase in the antioxidant effect of Toc as well as MGC.
Anionic oligosoap homologues (saponification products of alternating cooligomers of alkyl vinyl ether and maleic anhydride or diethyl maleate) having different side alkyl chain lengths, repeating unit numbers (n) and saponification degrees were used as the emulsifiers for the emulsion polymerization of styrene, and the relationship between the chemical structure of oligosoaps and their contribution to the emulsion polymerization was studied. Oligosoaps having n of several tens and side alkyl chain lengths of C10 or higher than C10, enhanced the emulsion polymerization. The particle sizes of the latices formed were below 1000Å, and the latices showed on good dispersion stability and low foaming properties. The conditions of the solubilizing sites (hydrophobic domain) of the oligosoap homologues are discussed focusing on the relationship between the initial rates of emulsion polymerization and the ability to solubilize styrene.
Correlation between phase behavior and the interfacial tension at oil/water interface, γo-w, has been studied in a three-phase region of CnH2n+1 (OCH2CHCH3) 3 OSO3M/C8H17 (OCH2CH2) 2 OH/brine/oil system (n=12, 16; M=1/2Ca, Na). γo-w reaches its minimum, γmino-w, in the midst of the three-phase region consisted of water, surfactant and oil phases, and γrmino-w attains to ultralow value 10-4-10-5mN·m-1. γmino-w decreases with an increase in the hydrocarbon chain length of surfactant or with a decrease in that of oil. The effect of salinity on γmino-w is also discussed.
The hydration and oxidation of α- and β-pyronenes (1), (2) with chlorinated acetic acids (mono-, di- or trichloroacetic acid), in polar aprotic solvents [dimethyl sulfoxide (DMSO), N, N-dimethyl formamide (DMF), sulfolane (SF), and ethylene carbonate (EC)] or lead tetraacetate were investigated. The results obtained are as follows : Hydration of (1) gave 1, 2, 6, 6-tetramethyl-2-cyclohexen-1 β-ol (10) with good selectivity. In EC, the oxidation of (1) gave 2, 3, 4, 4-tetramethyl-2, 5-cyclohexadien-1-on (9) as the main product (maximum in a 91% conversion). 1, 2, 3, 4-Tetramethyl-benzene (5) and cis-2-hydroxy-5, 5, 6-trimethyl-3, 6-cyclohexadienemethanol (23) were obtained as two main products by the oxidation of (1) with lead tetraacetate. In DMSO, the oxidation of (2) gave 1, 2, 6, 6-tetramethyl-1, 3-cyclohexadien-5-on (8) as the major product. The oxidation of (2) with lead tetraacetate gave cis-1, 2, 6, 6-tetramethyl-3-cyclohexene-1, 2-diol (22) in high conversion (71% at optimum). The reaction products were identified by comparing their of IR, NMR and GC-MS spectra with those of the authentic samples.
3-Methyl-4-octanolidea, γ-lactone known as a constituent of alcoholic beverages as Quercus lactone or Whisky lactone was synthesized from readily available starting materials. The synthetic route is shown in Scheme-1. The Michael reaction of nitropentane (1a) with methyl crotonate (2a) catalyzed by DBU in DMSO gave methyl 3-methyl-4-nitrooctanoate (3a) in 80% yield. Methyl 3-methyl-4-oxooctanoate (4a) was obtained from (3a) by Nef reaction with the electochemical oxidation in 88% yield. Reduction of (4a) with sodium borohydride gave a mixture of trans-, and cis-Quercus lactone (5a), and (5b). Similarly, trans-3-methyl-4-nonanolide (6a), reported as a constituent of cognac, was prepared from methyl 3-methyl-4-nitrononanoate (3a).