N-(p-Substituted benzenesulf onyl)-isocyanodichlorides were prepared from the corresponding benzenesulf onyl-isothiocyanates and chlorine in a good yield. Similar reactions, however, did not take place between highly dissociative low polymers of isothiocyanate and chlorine.Following reactions of the isocyanodichlorides were also investigated. (1) Form-ation of carbamic esters and imidocarbonic diesters by treatment with alcohols and sodium alcoholates; (2) formation of chloroformamidines and guanidines by treat-ment with amines and amides; and (3) formation of tritosylguanidine by treatment with tosylamide.

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Bromination of 3-phenanthrol(1)was investigated inconnectiotion with of its chlorin-ation reaction which is known to effect stepwise substitution at the 4- and 9-positions. Thus, upon treatment of (1) with an equimolar amount of elementary bromine dissolved in carbon tetrachloride or glacial acetic acid at room temperature, 9-br-omo-3-phenanthrol (2) was readily obtained as a sole product. Further bromination of (2) in carbon tetrachloride gave practically pure unstable 4, 9-dibromo-3-phen-anthrol (3), whereas that in glacial acetic acid, predominantly the stable 2, 9-dibromo isomer (4). Bromination of 4-chloro-3-phenanthrol or chlorination of (2) with sulfuryl chloride gave a common proruct, 4-chloro-9-bromo-3-phenanthrol (7). An attempt to obtain a tribromo compound from (4) was unsuccessful, while chlorination of (4) with sulfuryl chloride readily gave the corresponding 4-chloro compound, the structure of which was confirmed based on its alternative formation by bromination of (7). Bromination of the methyl ether and the acetate of (1) resulted in 9-substitution in the following order of readiness: OH>OCH₃>OCOCH₃. In order to establish the structures of the newly obtained phenanthrols, some compounds including 3-methoxyphenanthrene-4, 9- and -2, 9-dicarboxylic acids were synthesized.

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In conjunction with the anomalous behavior of 3-phenanthrol (1) in its bromination reactions as reported in the preceding paper, rearrangements of the 4-halogen substituent of (1) were investigated.Thus, 4, 9-dibromo-3-phenanthrol (3) was transformed rapidly into the 2, 9-di-bromo isomer (4) when heated in glacial acetic acid in the presence of hydrogen bromide. On the other hand, 4-chloro-3-phenanthrol (6) was converted only slowly into the 9-chloro isomer under similar conditions. In the former case, it was successful to isolate free bromine and 9-bromo-3-phenanthrol (2) from the reaction mixture as reaction intermediates suggesting an intermolecular rearrangement. It was also concluded that (3) and (4) were probably the "kinetically and thermody-namically controlled bromination products" of (2) respectively. Results were discussed in terms of steric hindrance at the 4-position.Preliminary results indicated that (3) was sensitive to alkali as well as to acid. Thus, when dissolved in a cold aqueous alkali-solution, it lost one of its bromine atoms to yield an alkali-insoluble matter.

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1-Chloropropane, 1, 1-dichloropropane, 1, 1, 1-trichloropropane, neohexane, and t-butyl chloride were photochlorinated at 40°C in the presence of 2, 2-dichloropro-pane, and relative amounts of the chlorinated products determined by g.l.c. The reactivities of C-H bonds toward hydrogen abstraction by the chlorine atom were compared with that of a C-H bond in 2, 2-dichloropropane. A linear free energy relationship was found to exist between the reactivities of methyl hydrogens and the Taft's σ constants for the substituents (CH₃, CH₂Cl, CHCl₂, CCl₃, CH₂CMe₃, CH₂CH₂Cl, CH₂CHCl₂, CH₂CCl₃, CMe₃, CMe₂Cl, CMeCl₂). p=-0.85. Results show that the reactivities of methyl hydrogens are mainly affected by the polar nature of the substituents, and resonance stabilization of the incipient radical by hyperconjugations is of minor importance.

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