INDIAN J. CHEM., VOL. 21A, JUNE 1982

[Sl-l and k;l against [OH-]-l) for glucose, galactose,fructose or mannose are very close to each other,again, substantiating the validity of the rate law(Eq. 8). The rates of enediol anion formation forn-glucose, n-galactose, n-fructose and n-mannosefollows the order: n-fructosec-n-glucose e- n-galac-rose > n-mannose, The relative rates of enediolanion formation for n-glucose, n-fructose and D-mannose are 1.0, 2.98 and 0.37 respectively; how-ever. these values are in the same order as has beenreported earlier".

We are thankful to Shri Sumitava Ghosh, Depart-ment of Physiology, Institute of Medical Sciences,BHU for analysing the sugars in the equivalencestudies.References

1. NAIR. C. G. R.• LALITHAKUMARI, R. & SENAN, P. I.,Talanta. 2S (1')78), 525.

2. F£IGL, F., Spot tests. Vol. II (Elsevier Publishing Co.,New York) 1')54, 245.

3. AGRAWAL, M. C. & MUSHRAN, S. P., J. Cliem. Soc.,(1973), 76''.

4. MAZZUCHIN, A., THIBERT, R. J., WALTON, R. J. &PADLEY, E. C,; Mikrochimica Acta (Wein). (1971), 285.

5. BHATTACHARYA. N. & SEN GUPTA, M. L., Indian J.cuo«, 5 (1967), 554.

6. Text book of biochemistry, edited by E. S. West, H. R.Tc·dd, H. S. Mason & J. T. Van Bruggen (The MccmillanCo/New York and Collier Macmillan Ltd. London),1%,196.

7. ISBELL, H. S., LINEK, K. & HEPNER, JR. K. E., Carbo-hydrate Res., 19 (1,)71). 319; SPECK, J. c., Adv. Car-boliydr, Chem., 13 (1954), 63; SINGH, M. P., SINGHA. K. & TRlPATHI, V., J. Pliys. Chem., 82 (1978), 127.2.;ANET, E. F. L. J., Adv, Carbohydr. Chem., 19 (1964),18!.

8. MACLAURIN, D. J. & GREEN, J. W., ca« J. Chem., 47(1969), 39L!·7.

Synthesis & Characterisation of Lithium Hexaortho-periodatonickelate(IV)t

L. C. W. BAKERDepartment of Chemistry, Georgetown University, Washington

D. C., USAand

H. G. MUKHlJUEE*, S. B. SARKAR & B. K. CHOUDHURY,Pure Chemistry Department, University College of Science,Calcutta University, 92, Acharya Prafulla Chandra Road,

Calcutta 700 009

Received 15 June 1981; revised 12 November 1931;a ccepted7 December 1981

A new hetcropoly periodate or niekel ((V) has been preparedas its lithium salt Li.NiI.O •••6H20. Further characterisationis based on chemical analysis, IR, ESR spectral measurements,thermal and magnetic measurements and potentiometric titrationand oxidation number determination. Its probable structurebas also been propose.d.

THE use of periodate ion as a strong oxidantand as an efficient stabiliser of high oxidation

states of transition elements was described by

tPrcvious paper : Indian J. Chem .• 19A (1980),539,

618

Malaprade'. The nickel (IV) periodato compoundwas first described by Ray and Sarma Z as insolublescdium and potassium salts, Na/KNiIOs. nHzO.Attempt for preparing a soluble nickel periodatocomplex by Malaprade! was unsuccessful. X-raystudy of KNiIOs was made by Vannerberg andBlcckhammer".

The present note describes the synthesis and pro-perties of a new heteropoly periodate, Li2NiIs024,6H20, analogous to the corresponding Co(HI)'and Fe(III)5 derivatives.

All the reagents used were of AR grade.Preparation of Li2 Nil6024, 6H20 - Nickel sul-

phate heptahydrate (2g) was dissolved in water(10 m!) and this solution was added to a solutionof 4N KOH (50 m!) containing KI04 (I g). K2S20S(5 g) was then gradually added to the mixture andstirred for 3 hr. The resulting brown solution wasfiltered through a sintered crusible and to the filtrateone equivalent lithium sulphate (0.5 g) solution wasadded. A brown precipitate was obtained whichwas filtered through a sintered crusible, washed withwater till free from alkali. It was then washed withether and finally dried in a vacuum desiccator.

Nickel was estimated using dimethylglyoxime afterdecomposing the compound with N~S03 and hydro-chloric acid; iodine following the method of Willardand Furman"; lithium by atomic absorption spectro-photometer and water was determined from the lossin mass by heating the sample at 140"C for 3 hr.(Found: Li, 1.09; Ni, 4.40; I, 57.45; H20; 8.00.Li•.Nils024, 6H20 requires Li, 1.05; Ni, 4.37; I,57.46; H20, 8.14 %).

The compound is brown in colour, which fadeswithin a few days, but persists for two weeks if keptin a sealed tube. It decomposes in strong acidmedium but is stable in alkaline solution.

Oxidation number was determined by reducing aknown weight of the compound with the knownweight of standard Fe(II) sulphate in 2N H2S04,From the amount of Fe(II) consumed it was foundthat each equivalent of Ni(ro4)~- oxidised 14 equi-valents of Fe(II). The reaction can be described byEq. (I)

Ni(I04)~- + 14 Fe2+ + 12 H+ -+Ni2+ + 14 Fe3+ + 610; + 6 H20 ... (1)

Equation (I) shows that nickel is present in thecompound as Ni(IV).

Potentiometric titration of Li2Ni(I04)., 6H20 withstandard Na2SOa solution using a Philips potentio-meter shows an inflection at a potential of 0.38 V(vs SeE). The volume of Na2S03 solution at thisinflection point corresponds to 25 equivalent per molof the complex. This indicates that Ni4+ and (104)1-ions are completely reduced to Ni2+ and 1- respec-tively. The process of reduction may be representedby Eq. (2)

Ni(ro4)~- + 25 SOi- + H~O -+Ni2+ + 61- + 25 SO!- + 2H+ ... (2)

The potential value indicates that Ni(I04)i;- is astrong oxidant. It oxidises sulphite to sulphate.

o -'vi• I

00(1)

iodide to iodine, ferrous to ferric, arsenite to arsenateand sulphide to sulphur' in acid medium.

The magnetic susceptibility of the compoundmeasured on a Gouy balance is -349.6 X 10-6 B. M.at 302K, indicating the compound to be diamagnetic.ESR spectrum (X-band with 100 Hz field modula-tion) of the brown coloured alkaline solution (seemethod of preparation), did not exhibit any bandconfirming the diamagnetic nature of the solutioncontaining Ni(I04):- ion. The IR spectrum of thecompound recorded on a Perkin-Elmer models 577instrument in CSI phase exhibited a strong andbroad band in the region 3500-3360 em"! assignableto hydrogen, bonded (OH 0) vOH. Thecorresponding aOH appeared at 1650 crrr-'. Inaddition peaks at ]470-1420, 710 and 600 cm-1have been assigned to ar·OH, '11-01 and vI-O(H)respectively. The aO-I-O appeared as multiplepeaks in the range 450-250 cnr-'. vNi-O could notbe detected. Too many bands in the lower rangemay be due to distortion in the octohedral geometryround iodine atomv".

The electronic spectrum of the brown colouredmother liquor in KOH recorded on a Varian Tech-tron instrument, exhibited a shoulder with highextinction (IE = 27,500) at 410 nm. The band inthe visible region could be assigned to the transitioninvolving charge transfer from metal tu orbital toligand orbital. The band at 210 nm was assignable'?to 10~ - species. Electronic spectrum thus esti-blishes octahedral geometry'! both round nickel andiodine atoms. The intense colour of the compoundmay be due to some type of covalency and may alsoarise from distortion in the octahedral geometry.

The compound gradually decomposed at 750°Cto give Li20, NiO, 12, H20.

Li2NiI6024, 6H20 may be considered to havestructure similar to that of TeMo60g~ ion12 (seestructure I). It has the Anderson. Evans modeland is a 1:6 hcteropoly acid. The nickel ion occu-pies the central octahedron and is surrounded bythe six lOGoctahedra. There will be some distortionfrom the idealised octahedral geometry due todifferent Ni-O and 1-0 bond lengths. ICVI!) possessall the criterion to function as an addendum inheteropoly complexes because of its small size, high

NOTES

positive charge and ability to take tetrahedral andoctahedral geometry with oxygen. This compoundbelongs to a new category of heteropoly species.A complete structure determination by Xvray crystal-lographic measurement will be communicated latter.

The authors thank Dr N. R. Sengupta, GSI,Calcutta. for atomic absorption measurements oflithium, Dr A. Roy, Saha Institute of Nuclear physics,Calcutta for the ESR spectrum and Dr B. K. Sen,Department of Pure Chemistry, Calcutta University,Calcutta, for active help and valuable suggestions.

References1. MALAPRADE, L., C. r. hebd. acado seanc. Paris., 204

(I 937) , 979; 210 (1940), 504; 238 (1954). 2:}22; BullSoc. chim. Fr., 5 (1938), 582; 7 (1940), 43; 6 (193'),223; 9 (19J,2), 832.

2. RAY, P. & SARMA, B .• J. Indian chem. Soc., 25 (1948),205; Nature 157 (1946), 627.

3. VANNERBERG, N. & BWCKHAMMER, I., Acta chem. scand.,19 (1965), 875.

4. NYMAN, C. J. & PLANE, R. A., J. Am. chem. Soc., 83(1960),2617; BAKER, L. C. W., LEBIODA, L., GRO·CHOWSKI, J.. MUKHERJEE, H. G., J. Am. chem. Soc.,102 (1980), 3274.

5. CAMBELL, M. J. M. & NYMAN, C. J., Inorg, chem., 1(1962), 842.

6. WILLARD, H. H. & FURMAN, N. H., Elementary quanti-tative analysis (D. Van Nostrand, New York), 1940,szo.

7. SIEBEitT, H., Fortschr. Chf!rn. Forsch., 8 (1967), 470.8. MUKHERJEE. H. G. & CHOUDHURY, B. K., J. Indian chem.

Soc., 56 (1979), 10')8.9. LOKIO, A. H. J. & KYRKI, J. R., Chern. Abstr., 80 (1974),

9904g.10. CROUTHAMEL, C. E. & MARTJN, D. S., J. Am. chem. Soc.,

71 (1949), 3031.11. BAKER L.C.W. & WEAKLEY, T.J.R. J. inorg, nucl. Chem.,

28 (1966), 447; FLYNN (JR.) C. M. & STUCKY, G. D.,Inorg. Chem., 8 (1969), 3:}3.

12. EVANS, H. T. (JR.), J. Am. chem. Soc., 90 (1968), 3275.

Metal Derivatives of Organoantimony Compounds :Reactions of Anhydrous Ferric Chloride with Arylanti-

mony Compounds+

HEMANT K. SHARMA. SORAN SINGH, S. N. DUBEY & D. M. PURl·Department of Chemistry, Kurukshetra University,

Kurukshetra 132 119

Received 1 May 1981; revised and accepted 22 February 1982

Reactions or anhydrous ferric chloride with aryl antimonycompounds have been studied. Tetraphenylstibonium chloridereacts with ferric chloride to give complex salts [Ph.Sb][FeCI.land [(Ph.Sb)(FeCI.)h,Ph.SbCI while triphenylantimony dichlo-ride forms adducts of the type Ph"SbCJ z-2FeCI3• Ferric chloridereacts with trlphenylstlbine to form triphenylstibine dichlorideand in the process it is reduced to bivalent state. The com-plexes have been characterized on the basis of elemental analyses,Mossbauer and IR spectral data, magnetle susceptibility andconductivity measurements.

tThis paper was presented at the Symposium on MadanTrends ill Coordination Chemistry held on 6-8 October, 1980on the occasion of the Diamond Jubilee Celebrations of theInstitute of Science, Bombay.

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