Indian Journal of ChemistryVol. 25A. March 1986. pp. 250-252

Bimetallic Complexes of Nickeltl l) with Tin(lV) Chloride &Tellurium(lV) Chloride

T M AMINABHAVI*, N S BIRADAR, R H RAYTHATHA & M 0 PATIL

Department of Chemistry, Karnatak University, Dharwad 580003

Received I May 1985; revised and accepted 27 September 1985

A few binuclear complexes ofnickel(lI) with tin(lV)chloride or tellurium(lV)chloride have been synthesized. The complexesare light-blue to green in color and are nonelectrolytes in DMF solution. Elemental analysis suggests a I: I stoichiometry.Magnetic moment, electronic and infrared spectral results show that nickel(1I) changes its configuration from square-planar tooctahedral on forming bimetallic complexes.

We have recently reported the synthesis andcharacterization of a number of transition metalcomplexesl-6. In continuation of this work we nowreport the synthesis and characterization of a fewbimetallic complexes of nickeltll) with tellurium(IV)and tin(IV) chlorides.

Materials and MethodsAll the chemicals used were of reagent grade. The

substituted salicylaldehydes (la-d) and (II) wereprepared by Duffs method 7. Nickel(II) aldoximatesand 2-hydroxyacetophenones were prepared accord-ing to the standard methods". The ketoximes (Hla-e]were prepared by reacting 2-hydroxyacetophenoneand hydroxylamine hydrochloride in 1 : I molar ratioin an aqueous ethanolic medium.

The bimetallic complexes were prepared by mixingeither nickel(Il) aldoximates or ketoximates withtellurium(IV) chloride or tin(IV) chloride in drybenzene in the molar ratio of 1: I with vigorousshaking. The separated solid complexes were filtered,

HI

-tg(C.::: /0 .....R '- N H

OH(I)

(0) R= H ; (b) R = 4 - CH3 ;(c) R=5- CH3i(d) R= 5- CI

C\H3 ,O-H

R r8YC=N

~OH( lIT)

(0) R;H;(b) R=3-CH3;(c) R=4-CHJ;(d) R;C-CH3; (e) R:5-CI

250

washed repeatedly with dry benzene and dried in vacuoover P 20S' The dry solid was extracted using a Soxhletextractor for several hours and dried again.

Results and DiscussionThe bimetallic complexes are light blue to green in

colour, insoluble in. common organic solvents butsoluble in polar solvents such as DMF, DMSO, etc.The elemental analyses (Tables I, 2) indicate I: I(metal: ligand) stoichiometry. The molar con-ductivities of IO-J M solutions in DMF measured onan Elico-CM-82 instrument are too small (3-9 ohm - 1 em? mol- I) to account for the dissociation ofthe complexes and thus the complexes arenonelectrolytes.

The nickel(lI) aldoximates are diamagnetic and thisfact is indicative of a square-planar geometry. Theirbinuclear complexes with tellurium(IV) showparamagnetic behaviour, and the effective magneticmoments fall in the range 2.82-3.20 B.M., suggesting achange in configuration around nickeltl l) as a result ofreaction with tellurium(lV) chloride.

For monometallic nickelrl l) ketoximates themagnetic moments are in the range of l.3-l.6 B.M.suggesting oligomeric structure. However, uponreaction with either tin(l V) chloride or tellurium(l V)chloride the magnetic moments are shifted to the range2.70-3.12 B.M. indicating an octahedral geometry forthe bimetallic complexes.

The electronic spectra recorded on a Beckman DB-2recording spectrophotometer for nickell l I] aldo-ximates and ketoximates in the region 28700-8333 ern - 1 exhibit a medium intensity band around22200-16700cm -I as expected "!". Their binuclearcomplexeswith tellurium(lV) or tin(IV) chlorides exhibitthree weak bands in the region 2500-8333 em - 1 thatare attributed to the various d-d transitionsll. Forbimetallic complexes of nickel(II) aldoximates with

AMINABHAVI et 01.: BIMETALLIC COMPLEXES OF NICKEL(II)

Table I-Analytical and Physical Data of Bimetallic Complexes of Tellurium(IV) with Nickel(II) Aldoximates

SI. No. Molecular formula Found (Calc.) (%) Mag.moment

Te Ni N CI (8.M.)

Ni(C7H602Nh reci, 21.04 10.10 4.66 24.10 3.20(21.24) (9.80) (4.68) (23.74)

2 Ni(C8H802Nh TeCI. 20.09 10.17 4.90 23.20 2.85(20.25) (9.36) (4.46) (22.65)

3 Ni(C8H802Nh reci, 20.75 9.22 4.80 22.10 2.82(20.25) (9.36) (4.46) (22.65)

4 Ni(C7Hs02NCI)2 'reci, 18.35 9.40 4.11 30.40 3.10(19.04) (8.78) (4.10) (31.70)

5 Ni(C"H802NhTeCl. 18.91 8.20 3.70 20.65 2.83(18.13) (8.38) (3.90) (20.29)

Table 2-Analytical and Physical Data of Bimetallic Complexes of Nickel(II) KetoximatesSI. No. Molecular formula Found (Calc.) I~ Mag.

---------------- momentSn(fe Ni C N Cl (B.M.)

Complexes with SnCl.

6 Ni(C.H.02N),SnCl. 29.13 9.28 29.90 4.40 23.00 2.98(19.15) (9.47) (31.00) (4.52) (22.93)

7 Ni(C9H ,o02NhSnCI. 18.00 9.20 34.06 4.50 21.40 3.12(18.32) (9.06) (33.37) (4.33) (21.94)

8 Ni(C9H ,o02NhSnCI. 17.95 9.15 34.00 4.40 22.05 3.02(18.32) (9.06) (33.37) (4.33) (21.94)

9 Ni(C9H 'OO2N),SnCI. 18.05 9.20 33.75 4.27 22.20 2.70(18.32) (9.06) (33.37) (4.33) (21.94)

10 Ni(C.H 702CI)SnCi. 17.75 8.75 27.27 3.87 21.05 3.03(17.23) (8.53) (27.89) (4.06) (20.63)

Complexes with TeCI.

11 Ni(C.H.02Nh r-ei, 20.02 9.80 4.33 3.06(20.25) (9.38) (4.46)

12 Ni(C9H I002Nh TeCI. 20.00 9.34 4.32 2.85(19.36) (8.94) (4.26)

J3 Ni(C.H I002Nh TeCI. 20.16 9.20 4.06 2.91(19.35) (8.94) (4.26)

14 Ni(C9H IOO2N),TeCi. 19.13 9.40 4.50 2.84( 19.36) (8.94) (4.26)

15 Ni(C.H ,02NC1h TeCI. 18.02 8.90 4.30 2.91(18.24) (8.42) (4.02)

telluriurrul V), a shoulder occurring at 25000-23000 ern I may be assigned to the J A 2y--> J T2g(P)transition. The middle band shows splitting due tospin-orbit coupling and two bands appearing around16100and 14500cm - I are attributed to J AZg~JTzg(F)transitions. A band appearing at 8333 cm - I is ascribedto J A Z9 ~ J Tzg transition. These observations suggestthat the nickel (II) acquires an octahedral geometryupon reaction with tellurium(lV) chloride. In case ofbinculear complexes of nickel(I1) ketoximates witheither tellurium(lV) or tintl V), a shoulder at24500cm- I may be assigned to the JAly~JTlg(P)transition IvJ). The middle band is split due to spin-orbit coupling and the band at 14000cm- I is due to3Azy-.J'J'lgIF) transition Ivl). The third band

appearing around 8334cm - I is attributed to 3 A2g

~ J T2g transition (v d. All these results suggest that thesquare-planar (dSp2) nickel(II) has changed into anoctahedral (spJd2) form 9 - II.

The IR spectra of nickel(lI) aldoximates andketoximates in nujol as recorded on a Perkin-Elmer221 spectrophotometer in the region 4000-200 ern - I

are discussed elsewhere Il. In all the bimetalliccomplexes, a medium intensity band observed around3280-3200cm- I due to intermolecular hydrogen-bonded OH of nickel(II) ketoximates/aldoximates isshifted to the region 3400-3300 em - I suggesting theinvolvement of v-hydroxy group in bond formation.

In case of bimetallic complexes of nickel(lI)aldomixates with telluriumtl V), the V(C = N), appears

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INDIAN J. CHEM., VOL. 2SA, MARCH 1986

at 1600cm - I as a high intensity broad band withshoulders around 1550 and 1500 ern - I which are dueto the aromatic v(C = C) modes. The medium intensitybands observed in the regions 450-425 and 480-460cm - 1 are respectively assigned to v(Ni -0) andv(Te -0) modes. A bridging vibration of the type Ni-Cl-Te is observed+' at 325-310cm -I and a highintensity band, with shoulders, observed in the region380-350cm -I is assigned to the terminal v(Te -Cl).

In case of nickel(ll) ketoximates a band in the region1665-1650cm - 1 is assigned to v(C = N). The bands at1618 and 1590cm -I are respectively attributed to OHdeformation vibration and to various aromatic v(C=0 modes. The band which was originally seen at1280cm -I due to phenolic \(C =0) in ketoximatesfllla-e)

is shifted to 1340-1325 cm - 1 in the nickel(lI)ketoximates suggesting Ni - 0 bond formation. A highintensity band around 460-430cm - 1 is thus assignedto v(Ni -0) modeI5.16• Upon binucleation with tin(lV)chloride, clea vage of the existing hydrogen bonding innickel(Il) ketoximates takes place. The V(C= N) andthe - OH deformation vibrations appear respectivelyin the regions 1660-1645 and 1635-161Ocm-l. Theregions 490-450 and 390-350cm -I are respectivelyassigned 17 - 19 to v(Sn - 0) and v(Sn - Cl) modes. Thebridging vibrations of the type Ni -Cl-Sn areseen 13.20 around 320-300cm -I.

In bimetallic complexes of nickel(Il) ketoximateswith tellurium(IV) chloride, the -OH deformationvibration observed around 1618cm-I shifts to1600cm -I suggesting the involvement of -OH groupin coordination. Bands in the region 480-460cm - 1 areassigned to v(Ni-O) and v(Te-O) vibrations. Amedium intensity band in the region 370-300cm - 1 anda band around 320-300cm - 1 are respectively

252

assigned 13.19 to v(Te -Cl) and bridging vibrations ofthe type v(Te-Cl-Ni).

In all the complexes, a band in the region 565-520cm -1 is assigned to v(Ni - N) vibrations".

The foregoing facts suggest that the square-planarconfiguration of nickel(Il) in ketoximes or aldoximes ischanged into octahedral upon reaction with tin(IV)chloride or tellurium(lV) chloride.

ReferencesI Biradar N 5, Divakar M C & Aminabhavi T M,lndianJ Chern,

23A (1984) 586.2 Biradar N 5, Roddabasanagoudar V L & Aminabhavi T M,

Polyhedron, 3 (1984) 603.3 Biradar N S, RoddabasanagoudarV L & Aminabhavi T M,

Polyhedron, 3 (1984) 575.4 Aminabhavi T M, Biradar N S, Divakar M C & Rudzinski W E,

lnorg chim ACla, 92 (1984) 99.5 Aminabhavi T M, Biradar N S, Karajagi G V & Rudzinski W E,

lnorg chim ACla, 91 (1984) 49.6 Biradar N 5, Karajagi G V, Roddabasanagoudar V L &

Aminabhavi T M, Synth React inorg met-org Chem, 14(1984)773.

7 Duff J C, J chem Soc, (1941) 547.8 Vogel A I, Text book of quantitative inorganic analysis, 3rd Edn

(Longmans Green, New York), 1969.9 Gray H B & Ballhausen C J,J Am chem Soc, 86 (1963) 260.

10 Cotton F A & Wilkinson G, Advanced inorganic chemistry,(Wiley Eastern, New Delhi) 1976.

II Drago R S & Longhi R L, lnorg Chem, 4 (1965) 11.12 Biradar N S, Patil B R & Kulkarni V H,J inorg nucl Chern, 37

(1975) 1901.13 Adams D M & Chandler P J. Chem Commun. 3 (llJ66) 69.14 Clark R J H, Spectrochim Acta, 21 (1965) 955.15 Behuke G I & Nakamoto K, lnorg Chem, 6 (1967) 433.16 Fay R C & Pinnavaia T J, lnorg Chern, 7 (1968) 508.17 Jain 5 C & Rivest R,J inorg nucl Chem, 31 (1969) 399.18 Jones R W & Fay R C,lnorg Chern, 12 (1973) 2599.19 Ohkaku N & Nakamoto K, lnorg Chem, 12 (1973) 2440.20 Baker E N, Hall D & Waters T N, J chem Soc, A (1970) 400.21 Ueno K & Martell A E, J phys Chem, 60 (1956) 1270.