NOTES

Complexes of Trivalent Lanthanide Ions with Sc~Base Derived from Vanillin & Triethylenetetraamlne

ABu SHAHMA*,MOHAMMADATHAR & NASEERAHMADDepartment of Chemistry, Aligarh Muslim University, Aligarh

Received 16 October 1980; revised and accepted 7 September1981

Complexes of lanthanlde(Ill) ions with the schill base derivedfrom vanillin and triethylenetetraamine have been synthesised andcharacterised on the basis of elemental analyses, molar eondue-tance, magnetic moment, IR and thermal analysis data. Thethermograms show the elimination (OR) (OCH3)C.H.CH.group at low temperatures before the elimination of triethylene-tetraamine part corroborating the observation made on the basisof [R spectral data. This is a dear indication of the non-coordl-nation of the phenolic hydroxyl groups. The lanthanide fons inthe complexes exhibit eight c:oord.ination number.

A review of recent chemical literature shows thatcomparatively less work has been reported on

lanthanide (III) complexes of schiff bases>«,Synthesis of lanthanide (III) [except Ce(III), Pm(III)and Lu(III)] complexes with the schiff base derivedfrom vanillin and triethylenetetraamine and theircharacterization are reported in this note.

The schiff base, (I) (van. trien) was prepared bythe condensation of vanillin (Busch, Boake Allen,London) and triethylenetetraamine (Riedal, Germany)in the molar ratio of 2 : 1 in ethanol and purified byrecrystallization from ethanol by evaporation underreduced pressure.

The complexes were prepared by the reaction ofthe schiff base with rare earth chlorides (LnCI3,

( t I

from Leico Chemicals, U.S.A.) in ethanol in 1 : Imole ratio. The yellow precipitate obtained waswashed several times with ethanol and dried in vacuoat room temperature. The complexes were ana lysedusing standard methods. The analytical data arereported in Table I. .

The thermo grams of the complexes were recorded(between ambient and 600°C) on a manual apparatusat RRL, Hyderabad. DTA analyses were also carriedout at RRL, Hyderabad using a Leeds and North-rup apparatus (between ambient and 800°C at aheating rate of 10"C/min). Magnetic susceptibilitieswere determined at room temperature with a Faradaybalance, at the Department of Chemistry, BHU,Varanasi, Molar conductance of 1O-3M solutionsof the complexes in DMSO were determined with aPhilips conductivity bridge, model PR-9500, using adip-type cell. Infrared spectra of the ligand and thecomplexes were recorded in nujol in the range4000·200 cm-1 on a Perkin Elmer spectrometer, model

TABLE1 - ANALYTICALANDMAGNETICMOMENTDATA OF LANTHANIDE(lII)CoMPLEXESOF BIs(VANILLIN)-TRlIITHYLENETETRAAMINB

CompoundsFound (Calc.) % !'err. in

Decomp, B.M.temp. C H N CICC)

:[LaCI.(van. trien)(H.O).]CI.H.O 255 37.24 5.66 7.74 14.12 diamag,

!PrCI2(van. trien)(H.0)]CI.H2O(37.00) (5.05) (7.85) (14.93)

299 36.24 5.56 7.80 14.38 3.12

{NdCI,(van. trien)(HsO)]CI.H,O(36.90) (5.03) (7.83) (14.89)

225 36.00 5.45 7.68 3.81

{SmCI.(van. trien)(H.O.)]CI.H.O(36.73) (5.01) (7.79)

245 36.12 5.23 7.62 14.00 1.34

[EuCI.(van. trien)(H.O,)]CI.H.O(36.42) (4.97) (7.72) (14.69)

260-62 35.24 5.12 7.66 3.77

.{GdCI.(van. trien)(HsO).]CI.HsO(36.34) (4.95) (7.71)

235 35.89 5.25 7.35 14.15 7.97

fTbCI,(van. trien)(H.O).]CI.H.O(36.08) (4.92) (7.65) (14.55)

215 35.28 5.11 7.23 10.17

[DyCI.(van. trien)(H.O).]CI.H.O(35.99) (4.91) (7.63)

240 34.72 5.08 7.50 14.92 10.93

(HoCl.(van. trien)(HsO)JCI.H.O(35.82) (4.08) (7.59) (14.45)

24042 35.00 4.96 7.47 10.69

(ErCls(van. trien)(HsO).]CI.H.O(35.70) (4.87) (7.57)

225 35.28 4.94 7.50 13.65 10.08

{TmCls(van. trien)(H.O).]CI.H.O(35.59) (4.85) (7.55) (14.36)

229 34.21 4.99 7.42 7.90

{YbCI.(van. trien)(H.O).]CI.HsO(35.51) (4.84) (7.53)

250 34.18 5.11 7.39 15.21 5.37(35.31) (4.81) (7.49) (14.25)

185

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

621. Reflectance spectra were recorded in the range200-900 nm at room temperature at GND, Uni-versity, Amritsar,

On the basis of analytical data and molar con-ductances=' (53-74 ohrrr? em- mol-t) the complexesare represented as [LnCllvan. trien)(H20)2l Cl.H20.

The ligand, van-trien, shows bands at 1630 cm ?

(v C=C & v C=N), 15£0 em'? (aromatic ringvibrations), 1505 cm-1 (N-H bending), 1270 cm-1(in-plane bending of phenolic OH), 1155 em=(C-aromatic-O-C-aliphatic), 1115 em"! (v C-N) and600 em"? (out-of-plane OH bending).

The 1630 cm-1 band shifts mostly to higher frequen-cies by about 10-70 cm-l on complexation whereasthe 1580 cm-l band remains almost unchanged, andthe band at 1505 crrr-' shows a positive shift of10-15 ern"! on complexation. The bands connectedwith the vibrations of hydroxyl groups remain almostunchanged on complexation. This shows that de-protonation of the hydroxyl groups does not occur,and hence coordination of phenolic hydroxyl groupsis unlikely. The shifts in C = Nand N-H frequenciesindicate the coordination through all the four nitro-gens. In the IR spectra of the complexes, a bandappears in the region of 950-820 crrr? which may bedue to coordinated water, and a hump appears in theregion 3400-3300 crn"" which may be due to non-coordinated water. Bands appear in the spectra ofthe complexes in the region 320-300 cm-1 (vM-Cl)and in the region 410-375 cm-l (vM-N)lo.

Thermograms of La(Il!), Pr(Il!), Nd(IlI), Sm(II!)and Eu(III) complexes show peculiar features. In thelanthanum (III) complex, one water molecule iseliminated below lOO"C, whereas the remaining twoare eliminated at temperature much above lOO"C.Hence, it is concluded that the two water moleculesare coordinated, the third being just water of hydra-tion. Thermograms of other complexes are similar.All the complexes, thus appear analogous and eightcoordinated.

DT A curves show endothermic peaks at 280°,300", 315°, 280" and 315°C in the complexes ofLa(IlI), Pr(IIl), Nd(III), Sm(III) and Eu(III) respecti-vely These seem to denote elimination of the two(OH)(CCH3)C6H3-CH-groups from the complexmolecules.

Magnetic moments of the complexes when plottedagainst atomic numbers of the metal ions. give theusual unequal double humped curve.

Reflectance spectra of complexes of van. trien withPr(Il!), Nd(III) and Sm(II1) show charge-transferbands'! at 40815 and 29410 crrr-', 40815 and 30770cm-I, and ':;0815 and 29850 em= respectively.Other bands" are : {for Pr(lII) complex} 25315 crrr+(4/--+ 5 d), 14495 cm! (3H4 --+ID2); {for Nd(III)complex} 25000 crrr" (4/ --+ 5d), 17240 crrr-' (4/9/2--+2G7/J; {for Sm(III) complex} 36315 cm=! (6H512 --+4K'I/J, 24690 cm+! (6HS/2 --+ 6Pa/2), 21740 cm'(6HS/; --+ 4/13/2) respectively.

References1. DUTT, N. K. & NAG, K., J. inorg, nucl. Chem., 30 (1968),

:,.~.<)3.2. YAMADA, S., YAMANOl:CHI, J. & KUMA, H., Bull. chem.

Soc. Japan, 44 (1971), 1·~-~~.

186

3. ANSARI, M. SHAMEEM & AHMAD, NASEI!R, Acta chim :Acad. Sci. Hung., 86 (1975), 47.

4. ANSARI, M. SHAMEEM & AHMAD, NASEER, Acta chim. Acad.Sci. Hung .• 92 (1977), 27.

5. GREENWOOD, N. N., STRAUGHAN, B. P. & Wn.soN, A. E.,J. chem, Soc., (1968), 2209.

6. BRooMHEAD, J. A. & KANE-MAOUIRE, L. A. P., J. chem.Soc., (1967), 546.

7. HENRY, R. A. & DEHN, W. M., J. chem. Soc .• (1949),2297.

8. CHAWLA, K. L., PRASHAR, P. & TANDON, J. P., J. Indianchem. Soc .• 49 (1972), 555.

9. BIRADAR, N. S. & KULKARNI, V. H., J. inorg: nucl, Chem.,33 (1971), 3847.

10. SACCONI, L. SABATINI, A., J. inorg, nucl. Chem., 2S (1963),1389.

II. DIEKE, G. H., Spectra and energy levels 0/ rare earth ionsin crystals (lnterscience, New York), 1968.

Mixed Complexes of Palladium(II) Containing Ionicor Coordinated ThenoyItriftuoroacetone & Some

Amines

B. K. SAHU, S. B. MISHRA & B. K. MOHAPATRA·tDepartment of Chemistry, Ravenshaw College,

Cuttack 753 003

Received 16 December 1980; revised and accepted 10 September1981

A number of complexes of the type [PdL.]X.. [PdL.' XIXand [PdL"XIX, where X is the anion of thenoyltrifiuoroacetonate(tta); L is a heterocyclic nitrogen base like 3-ethylpyrldine, 4-ethylpyrldine or 3,S-lutidine; L' is piperidine or r-butyl amine,and L" is bipyrldine, have been syntheslsed by reacting Pd(tta).with excess of the amines. These have been characterised onthe basis of their analyses, infrared and 1H NMR spectra.

THE versatility of acetyl acetone (ac.acH) asa coordinating ligand is well known=". Bis

(acetylacetonato jpalladiumtfl)! and bis (ethylaceto-acetatojpalladiumflfj'' react with equimolaramounts of a number of bases to give products inwhich one of the chelating ligands is transformedinto the y-carbon (central carbon) bonded state. Thereaction of bis (acetylacetonato) palladium(Il) withexcess amines however leads to the displacement ofthe ~-diketonate ligand from the coordination spheregiving complexes with anionic ~-diketonate (outsidethe coordination sphere)", We have been studyingthe various linkage modes7-lo of ,B-diketones inpalIadium(II) and platinum(l.I) comp!exes. As ~part of this programme, reactions of bis (thenoyltri-fluoroacetonato) palladium(II) with a number ofnitrogen bases have been studied and the results arereported here.

All the chemicals used were of AR grade. K2PdCl4was dissolved in warm water by stirring and reactedwith an ethanolic solution of thenoyltrifluoroacetonein I :2 proportion. The conte,:ts were stirred !or10 min treated with aqueous sodium acetate solution(2-fold' excess) and stirred for 30 min. The yell?wprecipitate formed was filtered off, washed WIth

+Prescnt address: Chemistry Department, B. J. B. College,Bhubaneswar.