5 92 3

..13. 0.96 -{CH.h-

2.46

14. 0.65 -(CH2)z-1.80

4

NOTES

6 7 8

SCHIFF BASE OF THE TYPE (IV), VALVES OF R' ARE GIVEN1 : 2 (CHs).SiCI s- 2 C.HllNO. 5.05 5.95

(3.41)( light yellow solid, (6.12) (6.09)soluble in methanol, hotchloroform and DMF.

1 : 2 (CHa),SiCl a- 2 CloHlsNOa 3.88 5.19(2.45), light yelflw solid, ~5.76) (5.75)soluble in methanol, hotchloroform and DMF.

15.00(15.46)

490.8(459.1)

14.91(15.58)

430.3(487.1)

SCHIFFBASE OF THI! TYPE (V); VALUESOFX ARE GNEN

15. 0.55 -(CHz).- 1 : 1 (CHa).SiCI.,(C18HlsNzO.) 5.85 7.13 18.00 380.31.14 (1.69), light yellow solid, (7.07) (7.05) (17.86) (397.1)

soluble in methanol, hotchloroform and DMF.

16. 0.63 --(CH.)a- 1 : 1 (CH.)"SiCl.(C1,H1SN.O.) 5.01 6.59 17.07 520.11.38 (2.01), light yellow solid, (6.83) (6.81) (17.28) (411.1)

soluble in methanol, hotchloroform and DMF.

remains almost unchanged in the resulting complexes,thereby showing that the alcoholic or phenolic groupsof the schiff bases do not take part in the complexationreaction.

The mode of coordination discussed above getsfurther support from the PMR spectra of salicylidene-n-butylamine and its 1 : 2 silicon complex. The PMRspectrum of the schiff base shows the azomethineproton signal at 8.058 .. This' gets shifted downfield(9.118) in the corresponding complex due to the co-ordination of the nitrogen to the central metal atomthrough a dative bond. However, the phenolic protonsignal remains unchanged in the spectrum of itsderivative, indicating its non-coordination to thecentral metal atom.

One of the authors (J. K. K.) is grateful to theUGC, New Delhi for financial assistance under theSpecial Assistance Programme.

Referenc s1. AYLETT,B. J., Prog. Stereochem., 4 (1969), 213.2. AYLETT,B. J., J. inorg. nucl. Chem., 15 (1960), 87.3. AHRLAND,S., RATT, J. & DAVIES,N. R., Q. Rev. chem.

Soc., 12 (1958), 265.4. SINGH, 0. P., PRASAD,R. N. & TANDON,J. P., Acta Chim.,

84 (1975), 459.5. MEHROTRA,R. C. & BAJA!, P., J. organornetal. Chem., 22

(1770), 41.

Some Dimethylformamidyl Derivatives of AI(ID) ,Zr(IV) & Sb(V)

R. C. PAUL, B. N. ANAND, S. K. VASISHT& RAMESHKApooR*

Department of Chemistry, Punjab University,Chandigarh 160014

Received 6 September 1978; accepted 26 December 1978

AlCI.lCON(CH.).].3DMF, Al.CI.[CON(CH.).J •.4DMF,ZrCI.[CON(CHa).].3DMF, Zr[CON(CH.).J4: and SbCI.[CON(CHs)2].DMF, SbCI.[CON(CH.).J. and SbCl.[CON(CHa).J. have been prepared by the reactions of aluminium (llI),zirconium(IV) and antimony(V) chlorides with dimethylformamidylsodium. The nature of these compounds has been investigated bypreparing their compounds with Lewis bases, and by studying theirconductance, infrared and thermal behaviour.

(

IN continuation of our work on dimethylforma-midyls-", we report in this note the preparation of

dimethylformamidyl derivatives of Al(III), Zr(IV) andSb(V) by the reactions of the chlorides of these metalswith dimethylformamidyl sodium in differentstoichiometries. The analytical results and some ofthe physical properties are given in Table 1.

Al(IlI), Zr(IV) and Sb(V) chlorides are reported tocombine with DMF to give addition compoundsAICI3.6DMP, ZrCl4.2DMF4 and SbCI5.DMF. Thesechlorides even on refluxing in DMF under reducedpressure do not lose HCl gas and are recovered un-changed. Bismuth(IlI) chloride is reported to undergoa base-catalysed solvolytic reaction and BiCI2[CON(CH3)2]. DMF has been prepared". Dimethyl for-mamidyl derivatives of Al(IlI) , Zr(IV) and Sb(V)could not be prepared by this method. However,their reactions with dimethylformamidyl sodium havebeen very specific in preparing these substitutedproducts.

These compounds are extremely sensitive to mois-ture. Except for (4), they are all insoluble in C6H6,CCI4, C6H6N02, CH3N02 and CHsCN. Compound(4)is soluble in these solvents. Millimolar solutions of 4in CeH5N02 and CH3N02 are non-conducting.Compounds (1), (2), (3), (5), (6) and (7) are, however,soluble in DMF and their millimolar solutions showconductances which suggest their ionic nature".

These compounds do not lose carbon monoxide onheating as no step corresponding to its mass loss hasbeen observed in TG. Presumably the oxygen atomof the dimethylformamidyl group is bonded to themetal atom. The thermal decomposition of 1, 2and 3 has been studied.

The compound AICI2[CON(CH3)2].3DMF (1)undergoes mass loss of 56.1 % (calc. 56.3 %) between50° and 230° to give AICI2[CON (CHS)2] which loses77.5% (calc. 79.9%) between 230° and 340° to giveIj2(AI203.3H20). This hydrated oxide undergoesmass loss of 88.2 % (calc. 86.9 %) at 340-600°.AI2Cl3[CON(CH3)2]3' 4DMF (2) undergoes massloss of 20.6% (calc. 2l.8%), 75.5% (calc. 76.7%)and 84.9% (calc. 84.7%) in three steps at 60-I60~,160-400° and 400-600° to give AI2Cls[CON(CH3)2]s'

77

INDIAN J. CHEM., VOL. 18A, JULY 1979

TADLE1 - ANALYTICALDATA OF DIMETHYLFORMAMIDYLSANDTHEIR COMPOUNDSWITH BASES[R = CON(CH')2J

Compound Colour AM in DMF Found (%) (Calc.)(olmrIem2mol-l)

M CI C H N

AI 02R .3DMF(l} Light yellow 48 6.2 18.4 36.2 7.4 14.7(6.9) 08.2") (37.0) (6.9) (14.4)

AI. CIa Rs.4DMF (2) Yellow 45 8.1 15.8 37.1 6.4 14.1(8.1) (15.9) (37.7) (6.9) (14.6)

Zr CIa R.3DMF (3, Light yellow 46 19.1 22.1 28.5 5.7 11.5(J8.7) (21.8) (29.5) (5.5) (11.4)

Zr R, (4) White 23.2 38.8 6.8 15.2(24.0) (-) (38.0) (6.3) (14.8)

SbCI,R.DMF (5) Pale yellow 44 29.1 34.9 16.8 3.3 6.7(29.8) (34.7) (17.6) (3.2) (6.8)

SbOaR2 (6) Do 35 31.9 28.1 18.5 3.7 7.8(32.7) (28.6) (19.3) (3.2) (7.5)

Sb CI2Ra (7) Do 30 28.9 18.2 26.6 5.0 10.5(29.8) (17.4) (26.4) (4.4) (10.3)

Al CJ2.R J.5 NH3(8) White 13.3 36.8 17.3 5.8 17.4(13.8) (36.3) (18.4) (5.4) (17.9)

AI2CJ3Ra.2DMF.NH. (9) Do 9.3 19.4 32.8 6.0 15.2(10.0) (19.7) (33.4) (6.5) (15.6)

Zr CI3R.2DMF.Q (10) Light yellow 17.4 20.1 38.9 5.0 10.7(16.7) (19.5) (39.6) (5.0) (10.3)

Zr ClaR.2DMF.2NH3 (11) White 20.1 22.8 23.2 5.4 15.5(20.3) (23.7) (24.0) (5.8) (15.6)

SbCI•.R.DMF pie.(12) Light yellow 23.4 28.7 27.9 4·2 8.0(24.3) (28.3) (28.7) (4.0) (8.4)

SbCI,R.Q (13) Do 25.6 3\.1 30.5 3.0 5.8(26.2) (30.5) (31.0) (2.8) (6.0)

R = [CON(CH3)~1-; Q = quinoline; and pie. = y-pieoline

TABLE2 - PRINCIPLE IR BANDS OF COMPOUNDS(em-I)

Comp

1234567

~(C=O) ~(C-N)

1650 1300, 11201660-1610br 13101630 1300, 11001630 11001650 11551650 1300,1170-11501640 1300,1150

v(M-CI)

470450380, 300

340340, 280295

v(M-O)

550530465465465, 400465,400465,400

2DMF, AI20s.3H20 and Al20s respectively. ZrC13[CON(CH3)2].3DMF (3) undergoes mass loss of37.0 %(calc. 37.3%),44.4% (calc. 44.8%) and 74.0% (calc.74.8 %) in three steps at 100-200°, 200-240° and 240-550° to give ZrC13[CON(CH3h].1/2DMF, ZrC13[CON(CH3)2] and Zr02 respectively.

These measurements could not be made on com-pounds (5), (6) and (7) as they lose SbCl5 as a volatileintermediate. The mass loss values, therefore, donot correspond to their simple stoichiometric relation-ships.

Some prominent IR absorption bands (vmaxin crrr-') are given in Table 2. A strong broadband around 1650 has been assigned to v(C = 0) ofthe dimethylformamidyl group. The broad natureof the band may be due to more than one typesof v(C=O). The lowering of this band is accompaniedby a corresponding shift of vC-N to higher spectralregions. Bands below 550 which are not present inthe spectra of pure DMF or [CON(CHs)2t group

78

have been assigned to metal-oxygen and metal-chlorine bonds. Compound (5) shows a mediumintensity band at 340 which is close to that observedfor v(Sb-CI) in SnCI; ion". The presence of asingle v (Sb-Cl) band in this compound would suggesta six coordinated polymeric structure acquired bylinking through dimethylformamidyl groups. Com-pound (6), however, shows an additional weak bandat 280, due to v(Sb-CJ). The presence of twov(Sb-Cl) bands suggests that all chlorine atoms arenot equivalent. The terminal metal-chlorine modesare observed at higher spectral region than the bridgingones". A polymeric structure involving bridgingthrough chlorine and dimethylformamidyl groupsmay be visualized. Compound (7) exhibits v(Sb-Cl)band at 295. This may suggest a change in thesymmetry of the compound from an octahedralenvironment which has been suggested for 5 and 6.

The nature of these solvolysed products has beeninvestigated by carrying out donor-acceptor reactions.Compounds (1) and (2) combine with NH3 to givecompounds (8) and (9) respectively. Compound ('3)reacts with quinoline and NH3 to give compounds(10) and (11) respectively. Compound (5) reactswith y-picoline and quinoline to give products (12)and (13) respectively. It is interesting to note thatcompounds (6) and (7) do not react with any base.This may suggest that these compounds are coordi-natively saturated. It may be inferred from thesestudies that the Lewis acid character of substituteddimethylformamibyls decreases rapidly with incre-ase in the number of dimethylformamidyl groups.

References1. PAUL, R. C; ANAND,B. N. & KApOOR.,R., Indian J~Chem.,

15A (1977), 52.2. PAUL, R. c., ANAND,B. N., VASISHT,S. K. & KApOOR,R.,

Indian J. Chem., 15A (1977), 456.3. MoYIUs, W. G. & MATWIYOFF,N. A., J. phys. Chem., 72

(1968),3063.4. CLEARFIELD,A. & MALKIEWICH,E. J., J. inorg, nucl. Chem.,

25 (1963),237.5. HILGETOG,G. & TEICHMANN,H., Ber. dt. chem. Ges., 96

(1963), 1446. •6. MISHR.A,A. K. & TANDON,K. N., Inorg. Chem., 10 (1971)

1896. '7. GEARY,W. J., Coord. Chem. Rev., 7 (1971),i81.8. BEATTIE,I. R. & WEBSTER,M., J. Chem.Soc., (1963), 38.9. NAKAMOTO,K., Infrared spectra of inorganic and coordination

compounds, 1970 , pp 216

Studies on Metallic Azides : Part VIII - CoordinationCompounds of Azide Lanthanons

1. E. ABDEL-AzIZDepartment of Chemistry, Teachers Training Institute

Adellia, Kuwait '

Received 6 October 1978; accepted 8 January 1979

Solid azido complexs of Ianthanons having the general com-position, Ln(OH)Ns.H20(Ln = Pr, Nd, Sm, En, GII, Tb, Dy,Ho, Er, Tm and Yb) have been prepared and characterized on thebasis of elemental analysis, and IR and magnetic data.

IN previous papers>", we reported the preparationand characterization of azido complexes of some

light lanthanons, like Pr(IlI), Nd(Ill) and Sm(IlI).In the present investigation we describe the prepara-tion and properties of solid azid complexes to thegeneral formula Ln(OH)2N'3H20, where Ln = Pr,Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb.

The solid lanthanon azido complexes were preparedby the addition of excess sodium azide solution to theconcentrated solution of perchlorate of each lanthanonion and stirring the mixture for 24 hr. The tempera-ture was kept constant at '" 5°C to prevent evolutionof NH3. pH value was adjusted to 5.5 ± 0.2. Thisvalue was found to be the optimum value, since preci-pitation of metal hydroxide readly occurred at pH>5.5 while NH3 evolved at lower pH values. Theprecipitated complexes were filtered, washed with dis-tilled water to remove excess free azide and then withethanol and dried in vacuo.

NOTES

Infrared spectra of the complexes were taken inKBr on a Beckman 12 spectrophotometer in therange 200-4000 cnr". Magnetic measurements weremade using Gouy method, on a Bruker Magnet pro-vided with a sartorius electronic balance sensitiveto ± 0.01 mg. Manganese pyrophosphate was usedas the callibrant.

In analogy with our previously reported results>",it may be concluded that the addition of high concen-tration of azide ions to the lanthanon ions leads tothe formation of I :1 weak complexes. In this workthe solid complexes were isolated, and the analyticaldata, given in Table I, indicate the existence of com-plexes having the formula Ln(OH)2Na.H20. Allthese complexes are insoluble in organic solventsand melt >250°.

The infrared spectra of the alkali metal azides andazido-complexes of some metals have been reported+",In this work the IR spectra (vmaxin cm") of lan-thanon oxides; hydroxides and azido complexes werestudied. The IR spectra of metal hydroxides aremostly identical to those of the azido-complexes,except that the 1090-1150 bands in the former arecompletely absent in the latter. These bands maytentatively be assigned to the symmetric stretchingvibration of Ln-OH-Ln which is probably destroyedby the azide group in the azido-complexes. The bandsat 450-460 in the complexes may be ascribed to vLn-N.The vasN; at 2130 in uncomplexed N; appearsas split bands and the out-of-plane bending frequencyof N 3 at 640 also appears as split bands in the azidoycomplexes with sharp decrease in intensity; indicatingcomplex formation. The weak broad bands at 850-860 may be taken as indication for coordinated water.

The magnetic moment values of the present com-plexes were compared with Van Vleck and Frank"values, for uncomplexed metal ions (Table 1). Sincethe common coordination number of lanthanons hasbeen long known to be at least six, a possible poly-merization of the complexes may explain the analytical

TABLE1 - CHARACTERIZATIONDATA OF AZIDO CoMPLEXES

Metal Complexes ColourMetal(%) N(%) Magnetic moment (B.M.)

Calc. Found Calc. Found Obs. Calli

PrN.O.H. Green 59.98 60.50 17.89 17.97 2.78 3.62NdNsOaH. Mauve 60.53 59.27 17.63 17.33 2.64 3.68SmN.O.H. Yellow 61.53 62.06 17.20 17.84 1.28 1.65EuN.O.H. Pale Pink 61.77 61.62 17.08 17.32 3.40 3.50GdN.O.H. Colorless 62.57 62.74 16.80 16.98 7.90 7.94TbNsO.H. Pale Pink 62.82 62.98 16.61 16.82 9.52 9.70DyN.O.H. Yellow 63.34 63.15 16.38 16.61 10.05 10.61HoN.OsH. Yellow 63.68 63.50 16.23 16.38 10.45 10.60ErN.OsH. Mauve 64.01 64.12 16.08 16.22 9.25 9.45TmNsO.H. Green 64.24 64.30 15.98 15.90 7.15 7.62YbN.O.H. Colorless 64.79 64.83 15.73 15.60 3.81 4.55

79

(