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Thermal isomerizations of cyclopropylcarbinyl (1), cyclobutyl (2), cyclopentyl (4), and cyclooctyl (5) thiocyanates were effected in sulfolane and, where appropriate, less polar aprotic solvents. In these cases, formation of isomeric isothiocyanates at relative rates which paralleled the relative rate order observed for acetolyses of the corresponding p-toluenesulfonate esters indicated the intermediacy of cycloalkyl cations. The cyclobutyl related compounds, 1 and 2, isomerized to similar product mixtures but at vastly different rates. The product ratios observed in these cases did not resemble those from solvolyses of the analogous arylsulfonate esters, thereby suggesting that the partition of the intermediate ion(s) is governed largely by the proximity of the counterion in the intermediate ion pairs. Studies of the isomerizations of 1 with ionic and Lewis acid catalysts supported this notion. The larger cycloalkyl thiocyanates 4 and 5 isomerized only to their corresponding skeletally unrearranged isothiocyanate isomers 9 and 10, respectively. Reaction rates were in keeping with the relative driving forces to ionization for these secondary thiocyanates. Interpretations of the results are presented involving ion pair intermediates in which counterion position is largely influential in determining product compositions.

Nmr single resonance spectra were obtained on Varían HA 100 ( ) and A56-50 (18F) spectrometers. ( 19), 19F(!H), and i9p(i»F) double-resonance experiments were performed on a Varían HA-60 instrument operating at 56.4 and 60.0 MHz. Octafluorocyclobutane, CCLF, CF2CICF2CI, and C6H5CF3 were used as lock signals for the 18F experiments. The necessary irradiating field for the heteronuclear decoupling experiments was provided by a NMR Specialties Model SD-60B heteronuclear spin decoupler. All of the benzotrifluorides 5 were obtained from Columbia Organic Chemicals., -DifluorotoIuene was prepared from benzaldehyde and SF4.16 , , -DifluorochlorotoIuene. In a three-necked, 250-ml flask equipped with a thermometer, gas inlet tube, and reflux condenser was placed 30 ml of , -difluorotoluene and 50 mg of azobisisobutyronitrile. The flask was then heated to 70°while chlorine gas was bubbled through the reaction mixture. The reaction was followed by 18F nmr and by testing the effluent gas for HC1 and was found to be over in about 90 min. The product was then distilled: bp 140°, 61°(50 mm); nmr (CC13) multiplet 5 7.5, 19F 49.36.2,3,4,5,6-Pentafluorobenzyl Fluoride. The apparatus consisted of a 250-ml, three-necked flask equipped with an addition funnel, a motor-driven stirrer, and an exit tube leading to a Dry Ice trap connected to a vacuum pump. The apparatus was flushed with dry nitrogen and then 48 g (0.2 mol) of finely powdered HgF2 was placed in the flask and 10 g (0.04 mol) pentafiuorobenzyl bromide (Penninsular Chem Research) was placed in the funnel.After evacuation of the flask the bromide was then added dropwise to the rapidly stirred mercuric fluoride over a period of 15 min. The product which collected in the Dry Ice trap was then filtered from a few grams of NaF, yield 1.8 g (45%). The nmr spectrum is given in Table IV.Decafluorobenzhydrol was obtained from Imperial Smelters Ltd. Tris(pentafluorophenyI)carbinol was a gift from Professor R.

15, SKCUPRITY CLASS, (of thio rep~ort) UNCLA8SSIFING-Tr.. OEC&itSI.UIC AR547/55WNOaDI 16, DISTRIBUTION STATEMNENT (of thal Report) Approved for public release; distribution is unlimited. * 17. OISTMIEUTION STATEMENT rot the abot,.ct entered tIn Black 20, It different from Report) 1S, SUPSPLEMENTARY NOTES IS. NKILY WOR09 (Coantimue an reverse side it necessary and iden~tify by block nambet) *Hydrogen Peroxide Quantitative Analysis *Potassium Dichromate* Volumetrie Analysis,F errous Ammonium Sulfate Hexahydrate, Titrimetric Analysis U ~20. ABSTRACT (Comtinu, an reverse side if nocoeary~ and Identify by block nmisbeer.)4 This report documents an oxidation-reduction scheme for the volumetric analysis of hydrogen peroxide in the approximate range of 30 percent, but it is not limited to this range. The purpose of the proposed method is to provide a titrimetric, non-r instrumental method for the analysis of hydrogen peroxide. JAR 473 EDITION OF I NOVG5 IS OBSOLETE CLSFED ________ N OIO2.F'.O1468O~ KCUftITY CLASSIFICATION OF THIS PAGE ("o~n Dael Entered)