Chlorophosphonation and its related free radical reaction of phosphorus compounds were revie wed. In the chlorophosphonation of substituted hydrocarbons, the resonance effect of substituents on the intermediatealkyl radical is of importance in the determination the process of the reaction. The unstabilized alkyl radical reacts rapidly with phosphorus trichloride to give alkylphosphoranyl radical which leads further to alkylphosphonyl dichloride as a final product. But the resonance-stabilized alkyl radical reacts with oxygen rather than with phosphorus trichloride to give alkyl peroxy radical. In the cases of benzylic radicals or halogenbridged alkyl radical, they lead to diphenylmethane derivatives or β-haloalkylphosphorodichloridates as final products. The mechanisms of the formation of these products were discussed.
In the chlorophosphonation of unsaturated hydrocarbons, besides the addition of chlorine atom, the addition of intermediate PCl₄ radical to double bond are also of importance.
The bromophosphonation of unsaturated hydrocarbons was also discussed.

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The electron deficient center (carbonium ions or other cations) at the β-position from a metal in organometallic compounds is stabilized by a hyperconjugation (σ-π conjugation) which has shown a very large resonance effect. Such a conjugative delocalization of neighboring σ bonds is available without changing the reactant geometry and is termed “vertical stabilization”. Furthermore this is completely separated from the electron-donating inductive effect by means of the demonstration of stereo electronic requirements. The effects of structural changes on the magnitude of the vertical σ-π conjugation are also discussed in details.

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It was found that the reaction of aminoguanidine hydrobromide with cyanogen bromide gave 1-guanylseimicarbazide hydrobromide (1) and N¹, N²-diguanidinoguanidine hydrobromide (2) in 49.5% and 4.3% yields, respectively. The structures of these products were determined by elemental analyses and spectral data (IR and MS).
The acetylation of (1) and (2) with acetic anhydride and sodium acetate resulted in the formation of 3-acetamido-5-methyl-1, 2, 4-triazole and 3, 5-diacetamido-1, 2, 4-triazole, respectively.
Furthermore the deamination reaction of (2) occurred by the action of several bases to give cyclization product, 3-amino-5-guanylhydrazino-1, 2, 4-triazole, in good yield.

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The p- to o-ratio of nitrotoluenes formed by nitration of toluene in the presence of porous materials, such as Japanese acid clay, silica gel, active carbon, molecular sieves or diatom earth, was compared with that obtained by the usual nitration with mixed acid. In general, p/o increased more or less by adding the porous materials and showed tendency to increase when the proportion of nitric acid to the porous materials was decreased. Moreover, in the nitration of toluene adsorbed on the porous materials, the maximum p/o of 1.56 (with silica gel) was obtained, while the p/o by the usual nitration was 0.71. A part of such effect may be attributed to the steric-hindrance against o-substitution at fine porous spaces on the materials.

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The asymmetric hydrogenation of methyl acetoacetate to methyl 3-hydroxybutyrate was studied using Niplatinum metal-Kiselguhr catalysts modified with optically active tartaric acid. The optimal amount of platinum metals for obtaining high optical yields was about 1% by weight of the nickel in the catalysts. Generally Pd and Pt were the most effective among the platinum metals tested. The effects of solvents and additives on the asymmetric hydrogenation were also studied. Tetrahydrofuran and ethyl acetate were found to be preferable solvents. Addition of a small amount of acetic acid increased the asymmetric selectivity. The greatest asymmetric selectivity (optical yield=87%) was obtained in the hydrogenation with a modified Ni-Pd-Kieselguhr catalyst in tetrahydrofuran and a small amount of acetic acid.

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Alkylbenzenes containing trichlorovinyl group in α or β-position, were synthesised by the radical-induced condensation reaction of alkylbenzenes, such as toluene, ethylbenene and n-propylbenzene, with tetrachlorothylene in the presence of di-t-butyl peroxide at 120-130°C.
The yields of these condensation products decreased in the following order (shown by the starting alkylbenzenes) : Toluene (54.7%) > (Benzene, 52.0%) >Ethylbenzene (19.3%) >n-propylbenzene (15.0%).
Several dimers of alkylbenzenes were also formed in these reactions.

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The oxidation of 2 (10) -pinene [1] with lead dioxide in glacial acetic acid was carried out. Products, which were isolated by the distillation or GLC, were 1-methyl-4-isopropenylbenzene [2], l-β-fenchyl alcohol [3], trans-pinocalveol [4], α-terpineol [5], n-borneol [6], myrtenol, [7], trans-carveol [8], cis-carveol [9], and perillyl alcohol [10].
On the basis of the above results, reaction mechanism was discussed.

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Recent advances in the preparation of activated magnesium and zinc metals, syntheses of Grignard reagents from various organic halides using the activated magnesiums, and the reactions of the activated zincs and organic halides, especially Simmons-Smith reaction with methylene iodide are briefly summarized.

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Prior to 1940's, low purity aromatics were recovered from closely fractionated cuts of by-products in coal processing industry. During World War II, based on Edeleanu technology, Modified Sulfur Dioxide Extraction was used for the production of toluene.
The Udex process using liquid-liquid extraction was the first commercially available process for the economical separation of aromatics. “Udex Grade” aromatics rapidly become the benchmark of the industry. In 1960's Shell and UOP commercialized a new liquid-liquid extraction process using Sulfolane solvent.
Extensive commercialization of the Sulfolane demonstrated distinctly lower utility requirements and higher aromatic recoveries. Today, many solvents, for example N-methylpyrrolidone, dimethyl sulfoxide, N-formylmorpholine have been proposed by various licensors.

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