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The reactions of trialkylboranes with ferric chloride and thiocyanate in an aqueous tetrahydrofuran solution give the corresponding alkyl chlorides and thiocyanates in good yields. It was found that two equivalents of ferric salts per alkyl group of organoborane are required, and not only the first alkyl group of trialkylborane but other alkyl groups are also used.

The photoelectron spectrum of vinylcyclopropane has been measured by using the 21.22 eV helium resonance lines. Eleven ionization potentials have been observed. The values of the first two ionization potentials have been explained by the conjugative interaction between the σ-orbitals of the cyclopropane ring and the bonding π-orbital of the vinyl group.

Free-radical addition reaction of organoboranes to α, β-unsaturated ketones forms corresponding vinyloxyboranes (3) as the intermediate. Methanolysis of the dibromoderivatives which should be obtained by bromination of the initially formed vinyloxyboranes provides a convenient one-step synthetic procedure of α-bromoketones from organoboranes in good yields.

Lithium trialkylisopropenylborates readily available from trialkylboranes and isopropenyllithium give the corresponding isopropenylalkanes in good yields by treatment with iodine. This procedure was applied to synthesize monoterpene derivatives such as limonene, diprene and an isomeric dihydrolinalool.

Trialkylboranes are readily electrolyzed by using graphite as an anode in a sodium perchlorate-methanol solution containing sodium methoxide or a sodium acetate-acetic acid solution to give corresponding alkyl methyl ethers or alkyl acetates in good yields, respectively.

The electrolytic reduction of acrylonitrile using a mercury cathode in liquid airanonia employing ammonium perchlorate as a supporting salt was examined. It was found that acrylonitrile was dimerized to adiponitrile in an excellent yield without significant formation of by-products under such reaction conditions, compared with the usual cathodic reduction in an aqueous solution.

The carboxylation of diisobutene and 1-octene with carbon monoxide using Cu(I)carbonyl as catalyst in BF3–H2O takes place smoothly at room temperature to produce tertiary carboxylic acids in high yields. The present procedure is superior to that using the same catalyst in concentrated H2SO4, both from a point of view of high yield of carboxylic acids and ready separation of such acids from the catalyst layer.

The simultaneous chemical equilibria and mass transfer of basic and acidic drugs through a two-phase compartment model were theoretically investigated. The model consisted of a well-stirred bulk aqueous phase, an aqueous diffusion layer, and a lipid barrier for perfect and imperfect sink cases. The nonsteady and quasi-steady-state changes in the concentration-distance distributions in the lipid phase were studied. The rate of change of the total drug concentration in the bulk aqueous phase was described in the general form of a first-order equation useful for the evaluation of experiments. A limiting steady-state relationship involving the transport rate with the partition coefficient, pH at the aqueous-lipid interface, dissociation constant of the drug, aqueous and lipid diffusion coefficients, and thickness of the diffusion layer was derived. Increasing the agitation rate in the aqueous phase markedly affects the pH profiles for the rate of transport. The pH-partition theory is shown to be a limiting case of the more general approach presented.

Geometrical isomers of 2,4-dinitrophenylhydrazones of asymmetrically substituted benzophenones were isolated in pure form by recrystallization. The configurational assignments to their E- and Z-isomers were made using electronic and NMR spectral data.

The molecular structure of 4-bromobenzophenone 2,4-dinitrophenylhydrazone was determined by X-ray analysis.

An account was given of the surface acidic properties of a series of BF3-treated aluminum oxides, ranging in their precalcination temperature up to 1000°C. It was concluded that all aluminum oxides dehydrated over 300°C were converted to solid acids with new strong acid centers of H0=-8.2 by adsorption with BF3. This new acid centers would be certainly of the Brönsted type. Their catalytic activities in some carbonium ion type reactions are well correlated with the n-butylamine acidity in the presence of Hammett’s indicators, and the maximum number of acid centers was observed in catalyst samples precalcined at 450 and 800°C respectively. The present study also suggests that the acid centers developed on the surface of aluminum oxides are somewhat different in nature depending upon their precalcination temperatures. Since there was a good correlation between the amount of the remaining hydroxyl groups and that of the absorbed BF3, the surface hydroxyl groups, in addition to the aluminum atoms serving as the Lewis centers, which are not fully coordinated, were discussed as the most important factors in the formation of such acid centers.

A series of experiments were conducted to demonstrate the validity of the baseline considerations presented in the accompanying communication and the usefulness of the combined experimental and theoretical approach in more complex situations. The experimental apparatus consisted of a water-jacketed chamber with controlled agitation. The lipid sink was prepared by saturating a filter with either dibutyl sebacate, hexadecane, or a combination of these oils with a polymer. A lipid sink made from a polymer-oil gel without the filter matrix was also used. A number of solutes which included diethyl phthalate, dinitrotoluene, and cholesterol were employed. The experimental results were found to be consistent with the predictions of theory. All solutes followed firstorder behavior when the oil-water partition coefficient was large. For moderate partition coefficient values it was necessary to account for the solute buildup in the oil at the interface. In order to explain the absorption of cholesterol from a 0.10% aqueous polysorbate 80 solution of cholesterol, an interfacial barrier was proposed.

As part of a program aimed at the quantitation of factors involved in the oil-water interphase transport of drugs, a two-phase model was theoretically investigated. The model essentially consists of the transport of the drug from an aqueous phase of a given volume across an aqueous diffusion layer of defined thickness, the water-oil interface, and into a lipid sink. Three methods for treating this problem were developed for the one dimensional case. With the assistance of a digital computer the resulting equations were used to compute the effects of a number of variables over a wide range of conditions. The calculations showed that when the oil-water partition coefficient is large, the transport is aqueous diffusion controlled and first-order behavior is followed in the aqueous phase with time. Deviation from first-order behavior occurs when the partition coefficient is low, when the diffusion coefficient in the oil is low, when the diffusion coefficient in the aqueous phase is large, or when the thickness of the aqueous diffusion layer is small. These results are expected to be useful in the design and interpretation of both in vitroand in vivodata on drug transport.

Bromination of Dl-epi-inositol yielded two hitherto unknown dibromo-dideoxyinositols, along with two known bromo-deoxyinositols (Dl-5-bromo-5-deoxy-allo-inositol and Dl-1-bromo-l-deoxy-neo-inositol). The proton magnetic resonance spectroscopic studies of the dibromo-dideoxyinositols with the aid of spin decoupling technique established their configurations to be Dl-2,4-dibromo-2,4-didoxy-chiro-inositol and Dl-1,4-dibromo-1,4-dideoxy-chiro-inositol.