PERSULFATE OXIDATION OF ISOPROPYL ALCOHOL

hybridization which might invalidate general con- clusions) has led to the synthesis of 1-silabicyclo-. [2.2.2 ]octane (II) for comparison of reactivi...
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COMhlUNICATIONS TO

bridgehead silicon due to possible changes in bond hybridization which might invalidate general conclusions) has led to the synthesis of l-silabicyclo[2.2.2]octane (11) for comparison of reactivity with I.* CH CH/ CH

'CH? CH.

CH/

'CH? CHz I CH2\Ji,CH>

I1

I

THE

EDITOR PERSULFATE OXIDATION OF ISOPROPYL ALCOHOL

Sir: In a recent paper' Malinowski and Levitt have proposed a mechanism for the persulfate oxidation of isopropjl alcohol which involves in the first step a reaction between isopropyl alcohol and the persulfate ion

CH2

CH,\

,CH? s 1

H

H

Vol. 81

R:CHOH

+ SnOs

ki RCHOOS03 k-1

+ SO,-

H

The intermediate is then assumed to decompose to Treatment of 4-(%-hydroxyethyl)-tetrahydropy- the ketone and bisrlfate ion. ran5 with equimolar amounts of thionyl chloride and pyridine gave -1- (2-~hloroethyl)-tetrahydro- This may be shown to be incorrect by our obthat induced exchange of radioactive sulpyran, b.p. 71" (6 mm.); Anal. Calcd. for C;- servation fate with persulfate ion in the presence of isopropyl H130C1: C1, 23.9. Found: C1, 23.5. , T h e Grig- alcohol does not occur, whereas i t is required by nard reagent prepared from 4- (2-chloroethyl)- the above mechanism. When the reaction was tetrahydropyran in tetrahydrofuran was added to to 25% completion in the presence of S-33 excess silicon tetrachloride and gave 4-(2-trichloro- carried silylethy1)-tetrahydropyran (111) in 637, yield, labeled sulfate, the recovered persulfate had only b.p. 97" (3 mm.); Anal. Calcd. for C?Hl3SiOCl3: lo-* of the activity calculated for complete exSi, 11.3; C1, 43.1. Found: Si, 11 1; C1, 43.1. change. We also have observed that the addition of allyl Treatment of I11 with boron trichloride and then acetate decreased the rate of disappearance of perthionyl chloride gave I ,5-dichloro-3-(2-trichloro-sulfate from 2.30 X sec.--I (0.02 M isopropyl silylethy1)-pentane (IV) in 7Oy0 yield, b.p. 130" alcohol, 0.02 M persulfate, 0.02 M sulfate, pH 5, (2.5 mm.). And. Calcd. for C7H13SiC16. Si, 9.3; 60") to the value observed in the absence of isoC1 (attached to Si), 35.2. Found. Si, 9.2; C1 propyl alcohol (4 X sec.-l).Z The inhibition (attached to Si), 35.3. Ring-closure of IV with ex- of the oxidation of isopropyl alcohol by allyl cess magnesium in ether gave a 30% yield of the acetate indicates that the reaction must be a chain bridgehead chloride, 1-chloro-1-silabicyclo[2.2.2]- process, that the initiation step is the first order octane (V), b.p. 59' (8 mm.). A n d . Calcd. for decomposition of persulfate ion (probably to the C;HI3SiC1: Si, l i . 4 ; C1, 22.1. Found: Si, 17.2; sulfate ion-radical) and does r?ot involve isopropyl C1, 22.5. The infrared spectrum of V showed the alcohol, and that the propagation steps involve the absence of Si-HI C=C and Si-CHS. Compound V induced deconipositioli of persulfate ion. The is readily hydrolyzable and gives rapid quantitative reaction of the silicon-chlorine bond with 0 1 N species formed in the decomposition of the perion is, in the presence of allyl acetate, conalkali. Treatment of V with lithium aluminum sulfate srmed in initiating the polymerization of the latter. hydride in ether a t 0" gave l-silabicyclo[2.2.2]- In the absence of allyl acetate, it affects the oxidaoctane (11),b.p. 158" (733 mm.), m.p. 133" (sealed tion of isopropyl alcohol. capillary), with an infrared spectrum showing the The species which initiates the oxidation of the strong Si-H band a t 4.7 and lacking maxima for alcohol be either the sulfate ion-radical or the C=C, Si-CH, and Si-0-Si. iZnaZ. Calcd. for C7- hydroxylmay radical. The latter species has been H13SiH: Si, 22.2; H (attached to Si), 0.80; mol. shown to be involved iii the' decoiiipositioll of perwt. (cryoscopically in benzene), 126. Found: Si, sulfate ioii iri water3 arid may reasonably be ex21.9; H (attached to Si), 0.80; mol. wt. (cryo- pected to be i~ivolvedin this case also. I t appears scopically in benzene), 128. The kinetics and rate constant for I1 in the base- that only a reaction utilizing the hydroxyl radical accommodate the kinetics of the reactioll catalyzed solvolysis with hydroxide ion in 95% can (first order in persulfate and indeperldent of the ethanol, R,SiH OH- f SH R3SiOH f Hz alcohol concentration). Evidence for the particiS-, where SH represents solvent, have been de- pation of this species may be obtained from the termined. For reactions of R3SiH with OH- in observation that whereas the rate constant is inde95% ethanol a t 35' relative rates (ks) are, for (CZpendent of the hydroxyl ion concentration between H5)aSiH = 1; 11, 10; I, lo3; (CH2)4Si(CH3)H,10; @ H 5-8, in more basic solution i t decreases and (CH2)gSi (CH3)H, lo-]. levels off a t k = 0.2 x 1 0 - ~ sec.-l between PH The new reactivity data offer additional support 9.5-10.5. The simplest interpretation is that the for our earlier, preliminary hypotheska hydroxyl radical is converted to the less reactive COLLEGEOF CHEMISTRY A N D PHYSICS L H YOMMER oxygen ion-radical in the more basic s01ution.~ T H E PENSSYLVAXIA STATE UNIVERSITl

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UNIVERSITY PARK, PA 0 F BENAETT RECEIVED XOVEMBER 19, 1958 (4) A molecular model of I1 using accurately scaled Stuart-Briegleb a t o m models is easily constructed a n d shows only small strain a t Si a n d complete shielding of t h a t a t o m t o hack a t t a c k . A corresponding model of I c a n n o t b e made. ( 5 ) D. Kohlbark. E. Cekuviiikov, A . Kezek a n d 11. I'ianlauida. .lnn., 634,69 (1937)

(1) E. K. Llalinowski and I,. S. Levitt, THISJOURXAL, 80, 5334 (1958). (2) This technique w p first used by 1. 11. Kolthoff, E. J. Meehan a n d E. M. C a r r , ibid., 7 5 , 14:iQ (1R53), in studying t h e persulfate t,xidation of methanol. C i i I . 31. Kolthoff a n d 1 I.: hliller. L b d , 73, X I 5 5 i l U , - ~ l i ( 1 1 l i . J. H a r t , S. Gordon a n d 1 ) . ,\, Hutchison. i b i , j . , 76, t , I f , 1 , l P . i 3 ) , ha\ e presented e\-idence f o r tlie h g d r u x y l radical 1ldl ing a ,oh of a b o u t 'J

X kinetic scheme which will accommodate these facts is ki

s20*-+BSO4. Sod.-

HO.

RJCOH

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BOOKREVIEWS

Jan. 5, 1959

k, + H i 0 --+

HO.

+ HSO4-

ki

+ &Os= +K?C=O + HSO,- + soa.+ SO,.-

kj

+R*C=O

[SsOe”I

This scheme also will accommodate the decrease in rate constant observed with rather low concentrations of alcohol or of persulfate,’ for here other chain terminating steps become important, thus decreasing the chain length and correspondingly decreasing the rate constant.

k. + R2CHOH + H 2 0 + R?COH

R2COH

which leads to the rate law

+ HSO4-

Synthetic Methods of Organic Chemistry. T-olume 1%.BlLY. THEILHEIMER.Interscience Publishers, Inc., 250 546 pp. Fifth Avenue, Kew York 1, h‘. T.1958. xvi 16.5 X 23.5 cm. Price, $22.25. Dr. Theilheimer’s efforts provide the preparative chemist with annual installments of what amounts to an Xriadne’s thread out of the Labyrinth of current literature. The popularity of the well established series bears witness not only to its usefulness and excellence but also the increasing trend to entrust the problems created by the deluge of published scientific data to dedicated literature scientists. The series has been fully discussed and described in previous reviews, including several by the present writer, (THIS JOURNAL,1946, and following), and this reviewer considers his task completed by calling attention to the fact that the 1958 volume, S o . 12, has appeared. RESEAKCH DEPARTMEST CIBA PHARMACEUTICAL P R U D C C T S , ISC. H A N S HEYnrASs Srmrm, NEW JERSEY

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DEPARTMENT OF CHEMISTRY HARVARD UNIVERSITY K E S N E T H B. CAMBRIDGE 38, MASSACHUSETTS RECEIVEDXOTEMBER 12, 1958

wIBERC5

(5) University of Washington, Seattle 5 , Washington. Professor Hari-ard Uni\-ersity 1937-58.

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Comprehensive Inorganic Chemistry. Volume Seven. SSEED, Professor Emeritus of ChemEdited by M. CANXON istry, School of Chemistry, University of Xinnesota, and ROBERTC. BRASTED,Professor of Chemistry, School of Chemistry, University of Minnesota. The Elements and Compounds of Group IlrA. By HAROLDP. KLCG and ROBERTC. BRASTED. D. Van Xostrand Co., Inc., 126 Alexander Street, Princeton, S. J. 1968. ix 302 pp. 16 X 23.5 cm. Price, $7.50.

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This volume is divided into two parts. Part I (233 pp.) is devoted to the non-transitional elements of Group I V and certain of their compounds. Part I1 (42 pp.) is concerned with borides, carbides, silicides and related compounds. The title of this, the seventh volume in a series of eleven, is misleading in that the treatment is not comprehensive except in the special sense set forth by the authors, L e . , “comprehensive in the extensiveness of the fields covered rather than in the fullness of their treatment.” Accordingly, reader reaction t o this and its companion volumes will be determined largely by- whether the specific topic on which information is sought was one of those selected by the Ion Exchange Resins. Second Edition. By RoBERr K u s i s , authors for inclusion either briefly or in detail. Rohni and Haas Company, Philadelphia, Pennsylvania. The subject matter included in T’olurne Seven is indeed John LViley and Sons, Inc., 440 Fourth Avenue, LTew York extensive. I t ranges from more or less classical descriptive 16, N. 1. 1958. siii 466 pp. 15.5 X 23.5 cm. Price, and historical information of the type found in many fresh$11.00. man chemistry textbooks to data relating to thermodynamic properties and structural information that would be useful In a field that is growing as rapidly as that of ion-exchange it is necessary t o make periodic revisions in order that new primarily to the research worker. Of the more purely developments can be included. The second edition of descriptive sections, those dealing with glasses and with the allotropic fornis of carbon are noteworthy. “Ion Exchange Resins” is the most complete and authoritaEven though the ground rules adopted by the authors tive compilation in its field. Many developments which were treated in a cursory fashion in the first edition have provide complete latitude with respect to inclusion or omission of specific topics, the reader nevertheless expects some been expanded to form new chapters in the present work. The first four chapters which discuss the theory and basic internally consistent plan or viewpoint. Such is difficult principles of cation and anion exchange, as well as chapter to detect in the present instance. For example, only the original method for the synthesis of carbon suboxide is five which describes the synthesis and tabulates the propermentioned; a much superior procedure [cf. Hurd and Pilties of the many types of commercial ion-exchange materials, are of great value to chemists and chemical engineers in grim, THISJOURNAL, 5 5 , 757 (1933)l is not included and general. The next nine chapters which are devoted to there is no reference to the one review paper on the chemistry various applications of ion-exchange should be of special of this oxide [cf. Ryerson and Robe, Chem. Revs., 7, 479 (1930)l. On the other hand, silicon monoxide is discussed interest to the reader who wishes t o become thoroughly in more detail and all of the pertinent literature is cited. acquainted with ion-exchange technology. Chapters fifteen, sixteen and seventeen are written primarily for the Similarly, the section on the halides of carbon makes no chemical engineer and are essential t o a comprehensive dis- mention of the bromide or iodide, ]:et all of the halides of germanium are included at least briefly. Sumerous other sertation on ion-exchange resins. examples could be cited. J A C K E . POIYELL Part I1 of this volume represents an overly ambitious undertaking. Brevity and a high degree of selectivity are

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