Assuming Lewis′ scheme, mathematical formulation was given for the decay of organic phosphorescence, which would help us to judge whether the quenching action of the added substance affects on singlet or triplet state. The decay curves of Trypaflavine-filter paper phosphor in various con-centrations, were accurately measured by and, oscillograph, and from the results obtained, it was tentatively concluded that the triplet state is not affected much in the concentration quenching.
A surface rheometer was presented which enables the creep of surface films to be measured under constant shear stress. The main construction consists of a ring and a suspending torsion wire. Automatic adjustment of the torsion head driving, which made distorsion of the wire to be constant throughout the creep test, was accomplished by means of a phototube relay mechanism. The creep curve and its analysis data of ovalbumin monolayer were also presented.
The synthesis of 2-amino-2-methylglutaric acid from levulinic acid by Strecker’s method is reported. This acid gives 2-methyl-5-oxopyrrolidine-2-carboxylic acid on dehydration, and some of its esters were prepared and tested for plasticizer performance.
Methyl isobutyl ketone and phenylacetone, unlike methyl ethyl ketone, condensed with furfural by sodium hydroxide at their α-methyl groups irrespective of the reaction temperature, giving 1-(2-furyl)-5-methyl-1-hexen-3-one (III) and 4-(2-furyl)-1-phenyl-3-buten-2-one (V) respectively. 1-(2-Furyl)-5-methyl-1-hexen-3-one (III) gave the two forms of 2,4-dinitrophenylhydrazone. One (m.p. 145-146°) shifted readily to the other (m.p. 196-197°) in dilute alcoholic sulfuric acid, and those may be the syn- and anti-isomers. 4-(2-Furyl)-1-phenyl-3-buten-2-one (V) obtained here gave the two species of semi-carbazone which were converted into the respective two species of 2,4-dinitrophenylhydrazone. It may perhaps be composed of the cis- and trans-isomers. This furfurylidene ketone gave γ, ζ-dioxo-η-phenylcaprylic acid (VI) by the ring-opening in alcoholic hydrochloric acid.
3-Acetyl-4-(2-furyl)-3-buten-2-one (I) and ethyl α-propionyl-2-furanacrylate (V) were obtained by the condensations of furfural with acetylacetone and ethyl propionylacetate by piperidine, respectively. 3-Acetyl-4-(2-furyl)-3-buten-2-one (I) was oxidised by sodium hypochlorite to furfurylidenemalonic acid (II), and, on refluxing with alcohoric hydrochloric acid and subsequent hydrolysis, gave β-(4-acetyl-5-methyl-2-furyl)-propionic acid (IV). Ethyl α-propionyl-2-furanacrylate (V) gave γ,ζ-dioxopelargonic acid (VI) by refluxing with alcoholic hydrochloric acid and subsequent hydrolysis. The dioxocaboxylic acid (m. p. 83∼84°), obtained by the ring-opening of the furfurylidene ketone (b.p. 126°/19 mm.) in alcoholic hydrochloric acid which was considered to be 1-(2-furyl)-1-penten-3-one (VII) in the previous reports, was identical with this γ,ζ-dioxopelargonic acid (VI). It was confirmed, therefore, that the ideas in the previous reports6) was correct.
The polymerization of pure styrene has been studied photochemically near room temperatures and in the range 0 to about 70 % conversion, and the following results have been obtained. With increasing conversion; (1) both the direct photo-polymerization and the thermal polymerization are accelerated strongly, (2) the over-all activation energies in both polymerizations decreases, (3) the lifetime of kinetic chains increased steadily and the photochemical initial and after effects are easily observed dilatometrically over 30 % conversion. Also (4) the reaction order of chain termination is 2 in the range 0 to about 40 % conversion, but it becomes less than 2 at the conversions over 60 %. Thus these results have been discussed on several assumptions and it has been concluded that they are attributed to a considerable change in the mechanism of radical termination with increasing conversion of the reaction system, i.e., the change from an activation-controlled termination to a diffusion-controlled one.
The Michael addition of diethyl methylmalonate to ethyl crotonate-(carbonyl-C14) was carried out with one equivalent of sodium ethoxide; the addition product, diethyl α-ethoxycarbonyl-β,γ - dimethylglutarate, was hydrolyzed and the resulting acid decarboxylated by heating. The evolved carbon dioxide contained 42 % of the radiocarbon of the original ethyl crotonate. Thus it was demonstrated that the migration of an ethoxycarbonyl group took place in the course of the reaction from the methylmalonate moiety to the carbon atom α to the labelled ethoxycarbonyl group. The mechaism of the reaction is discussed.
The decomposition of N-nitroso-p-acetanisidide in nitrobenzene at room temperature yielded 4-methoxy-4′-nitrobiphenyl and 4-methoxy-2′-nitrobiphenyl in a ratio of 1: 1. 6. From the result of a similar experiment in a mixture of nitrobenzene and benzene, which compete for the p-anisyl radical produced from N-nitroso-p-acetanisidide, the relative reactivities of the ortho, meta and para positions of nitrobenzene towards the p-anisyI radical are found to be 7.24, 0, and 8.95, respectively, the reactivity of one nuclear position of benzene towards the same radical being taken as unity.
Cis- and trans-α,α′-Dimethylstilbene, heated with a little sulfuric acid at 210°, were isomerized to an equilibrium mixture consisting of 55% of the trans and 45% of the cis isomers. Heated with iodine at 210°, they yielded meso-2,3-diphenylbutane. The action of bromine produced 1,4-dibromo-2,3-diphenyl-2-butene; under certain experimental conditions the concurrent cis-trans isomerization was observed. This fact, together with the isolation of a small smount of α–bromoacetophenone as a by-product, supports the view that the reaction proceeds by a mechanism involving bromine atoms. The action of bromine on some α,α′-disubstituted stilbenes was examined. The reactions observed were discussed in terms of the steric effect exerted by the bulky groups at the ethylenic linkage.
The action of hydrogen bromide on cis- or Trans-α,α′-dimethylstilbene in the presence of a peroxidic substance or of bromine in carbon tetrachloride in the dark below room temperature caused a partial isomerization to the respective geometrical isomers. The reaction was inhibited by catechol. When oxygen was allowed to react simultaneously under otherwise the same experimental conditions, the cleavage of the central double bond took place yielding acetophenone and α-bromoacetophenone along with 1,4-dibromo-2,3-diphenyl-2-butene. Similar experiments with α-methylstilbene and α,α′-diethylstilbene were conducted. The action of oxygen and bromine on α,α′-dimethylstilbene caused the same oxidative cleavage of the double bond as with hydrogen bromide and oxygen. It was pointed out that an ethylenic compound which is sterically hindered to such an extent that it is unreactive towards molecular reagents can be reactive enough towards radical reagents.
The usual photochemical method and the rotating sector technique have been used to study the effect of conversion on the termination mechanism in the polymerization of methyl methacrylate. The strong rate acceleration, the extreme increase in kinetic chain lifetime and some decreases in the overall activation energy and the reaction order of chain termination have been detected with increasing conversion of the reaction system. These results are in good agreement with those reported on styrene in the first paper of this series and with the available data on this polymerization. These results have been discussed under several assumptions and confirmed to be due to a large change in the termination mechanism, i. e., from the activation-controlled termination of polymer radicals in the initial stages to the predominant diffusion-controlled termination in the later stages.