Simple as well as mixed ajyl thioketones were prepared in good yields by the action of hydrogen sulfide-hydrogen chloride on the corresponding oxo ketone.2. The above method is not applicable to the preparation of nitro thioketones.3. The substitution of a biphenyl or anaphthyl group for a phenyl group in thiobenzophenone greatly enhances the stability of the carbon-sulfur linkage.4. The new thioketones show the typical reactions of the thiocarbonyl group. They show absorption bands around 5900 Á. Chapel Hill, N. C.

The trialkylsilicyl fluorides were very stable and did not respond t o the action of sodium in liquid ammonia and therefore could not be analyzed by the sodium-liquid ammonia4 method.The fluorine was qualitatively determined in each compound by oxidation with chromic acid in sulfuric acid solution to silicon tetrafluoride which was passed into aniline6 t o form a solid addition compound. TABLE I PROPERTIES AND ANALYSES OF TRIALKYLSILICYL FLUORIDES Trialkyl-B. p., Euorides mm.) n% d'54 % Calcd. Found silicyl 'C. (745 Yield, Carbon, ' % Ethyl' 109 1.3900 0.8354 45.0 53.66 52.50 Propyl 175 1.4107 ,8339 62.0 61.28 60.93 Butyl 224 1,4250 ,8372 70.1 65.97 65.96 Amyl 267 1.4305 ,8389 57.6 69.10 69.10 (4) Vaughn and Nieuwland, I n d . Eng. Chem., Anal. Ed., 3, 274 (1931). (5) Comey and Jackson, Am. Chcm. J . , 10,166 (1888). Table I. The compounds were analyzed quantitatively for carbon by a modified Chalmer'se method which is a wet combustion method. The results of this analysis are given in SummaryA study was made of the reaction between silicon tetrafluoride and ethyl, propyl, butyl and amylmagnesium halides.Three new trialkylsilicyl fluorides were prepared.The fluorine atom in trialkylsilicyl fluorides is very inactive, much less reactive than the corresponding bromide or chlorides.The reaction between alkylmagnesium halides and silicon tetrafluoride is completed in less than one hour. NOTRE DAME, INDIANA (6) Chalmer, I n d . Eng. Chem., Anal. E d . , 4 , 1 (1932).

I'he work showed. that the a a methyl group to the nitr at,osn of the condensation p r o d i~t s vl" the orthoand para-hydroxy zro c~.~QI-s, 'but that coinpounds not possessing these orthoor jr!cera-phcnol groups did not acqtiire this property. A 1ittl.e preliminary work was d m c to tietermhe the suitability of these coiiilpounds to serve a.s indicators in vo 1 umehic analysis I alc~ehycles "ith qdnaldin gave these compoullds the properi:ies of iradi ~ CUUCINNATI, 5.

of any solid phase other than the monohydrate; cooling curves also gave no indication of a change of phase down to the eutectic temperature, -0.75°.By the method of least squares, the parabolic curve for the solubility was calculated with the following constants: wt. per cent, solubility = 2.314 + 0.06272/ + 0.001714/2. The solubilities at round temperatures calculated by this equation are given in Table II. When compared with the

Nef published his first work on the oxidation of sugars by Fehling's solution, or, more correctly, by a suspension of cupric hydroxide in an alkaline sugar solution, in Liebig's Annalen in 1907.~ The sugars studied were I-arabinose, d-glucose, d-mannose and d-fructose. Thereafter a series of investigations was undertaken by Nef, in part in collaboration with his students.3 The present work was undertaken in order to obtain more complete information with regard to the amounts of the oxidation products. Experimental proof of the production of certain acids, such as ribonic acid, was sought for. When I-arabinose was oxidized in alkaline solutions by air, E-erythronic, d-threonic, d-and I-glyceric, glycollic, formic and carbonic acids were produced. When oxidation was accomplished by cupric hydroxide, I-arabonic, I-glyceric, glycollic, oxalic, formic and carbonic acids were found among the oxidation products: 1-Ribonic acid was not found, although it was presumably produced, for d-lyxonic acid was found among the oxidation products of 1-xylose. Other products of oxidation of 1arabinose were obtained by Nef in former experiment^.^ When I-xylose was oxidized in alkaline solutions by air, I-threonic, d-erythronic, I-glyceric, glycollic, formic and carbonic acids were found to be present among the products. When oxidation was accomplished 1 The experimental work described in this paper was done by Dr. Nef during the two years previous to his death on August 13, 1915, with the assistance of Dr. Glattfeld and myself. I have undertaken to prepare the results of t h e work of this period for publication. Dr. Glattfeld has assisted in the preparation of this paper.-Oscar F. Hedenburg.