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resulting mixture was refluxed for 13 minutes with stirring. After dilution with water, separation and drying over anhydrous magnesium sulfate, the product was distilled at 75-76' at 1 mm. (rep0rted~980.5" a t 0.8 mm.) yielding 25.1 g. (72%) of colorless p-bromostyrene oxide, m.p. 27.1' (re-ported18 26').p-Bromostyrene oxide (26.9 g.) reduced with 3.0 g. (4!0%) of lithium borohydride, gave an 83% yield of a mixture containing 20.4 g. (91%) of a fraction distilling a t 86-92" a t 1 mm. [largely l-(4-bromophenyl)-ethanolz0~ and 2.0 g. (9%) of 2-(4-bromophenyl)-ethanol, b.p. 104 a t 1 mm. (reportedz1 b.p. 147' a t 10 mm., m.p. 36-38").The product of a duplicate reduction of P-bromostyrene oxide, obtained in 66% yield, was analyzed by infrared absorption. Comparison of the maxima at 2950, 2930, 1595, 1200, 1110, 900 and 750 waves cm.-I with synthetic mixtures of the two isomeric alcohols, indicated a composition of 84% of the secondary alcohol and 16% of the primary.1-(4-Br01nophenyl)-ethanol (b.p. 98-102.5" at 2 mm.) was prepared independently in 68% yield by sodium borohydride reduction of p-bromoacetophenone in aqueous methanol. The phenylurethan melted at 103.6-104.0" (reportedz0 103-104'). 2-(4-Bromophenyl)-ethanol (b.p. 138' a t 9 mm.) was prepared in low yield by the aluminuni chloride-catalyzed bromination of 2-phenylethanol. The phenylurethan melted at 127.&139.0° (reportedz1 126').The phenylurethan prepared from the 1-(4-bromophenyl)ethanol fraction of the p-brotnostyrene oxide reduction product melted a t 102.1-102.8" and did not depress the m.p. of an authentic sample of the 1-(4-bromophenyl)ethanol phenylurethan. The urethan prepared from the isomeric fraction melted at 129.2-129.7' and did not depress the m.p. of an authentic sample of the urethan of 2-(4-bromophenyl) -ethanol.Lithium Borohvdride Reduction of 0-Nitrostyrene Oxide.-p-Nitrostyren& oxide was prepared from commercial fitiitrophenacyl bromide by the procedure used for p-broniostyrene oxide. The yield of product twice recrystallized from ethanol was 55%; m.p. 84.2-85.4' (reportedza 85-86"), A solution of 14.8 g. of P-nitrostyrene oxide in ether, reduced by 4.0 g. (800%) of lithium borohydride, gave upon dis-(19) T. Bergkvist, Pdensk Kern Tid., 59, 20: (1047); C. A , , 42, ( 2 0 ) R. Quelet, Uiiil. S O T . chi^., [ i ] 45, 73 (192'!l), reportcd h.p. l.'lOo (21) T. 1%'. J. T a y l o r and P. SI. Hotsoii, J . Cheirr. Soc., 191 (193C). 2981 (1948). a t 12' m m .FRANK A. CASSIS VOl. 76 tillation 9.4 g. (63%) of an oil, b.p. 134-142' a t 2 mm., which partially solidified upon standing, and 4.3 g. (29%) of a tarry residue. The mixture was not quantitatively separable by fractional distillation. Infrared analyses of this and a duplicate product fix the composition a t 62% 2-(4-nitrophenyl)-ethanol and 38% 1-(4-nitrophenyl)-ethanol, by comparison with synthetic mixtures, of the absorption a t 2930, 1200, 1090, 1035, 900 and 840 waves l-(4-hTitrophenyl) -ethanol, prepared independently by the sodium borohydride reduction of P-nitroacetophenone, 2z boil...

The nuclear alkylation of phenol by t-butyl chloride is inhibited by dioxane, the decrease in reaction rate being proportional t o the concentration of dioxane. The inhibition can be quantitatively accommodated by assuming that a hydrogenbonded complex of 2: 1 pheno1:dioxane is formed, and that phenol so bound cannot participate in the alkylation reaction. The same explanation fits the data for tetrahydropyran if a 1 : 1 complex is assumed. The availability of the phenolic hy. droxyl, presumably for solvating the halogen of the alkyl halide, thus appears significant in the alkylation reaction.

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