-r-mo - niscairnopr.niscair.res.in/bitstream/123456789/52387/1/ijca 16a(4) 361-362.pdflnd1an j....

.....J<.NH

HN-C .•.•.

I ~R-HN-C, I °

S ...•••.t .,f"Mo CI2S/t'o

R-HN-C'

\ iHN-C ....

NH'R

[M002 (OPOTB)2] el2i R-R'=C& Hs[Mo02 (o.o.TOTBh] C12; RoO R- C6 H4 (CH3)(Ortho)

[MOO, (O.p.TOTB)2] C12; R - R' - C6 H4 (CH3)(para)

/RNH-HN--·C ...•.

/ ~R-HN-C... I

0....••.t /0Mo-r-R-HN-C" 0

\ iHN-C

NH ,'R

II

[M002 (OPTB)2]Cl,jR •• R'= C6HS

[MOO, (P.o ..TTB),J Cl2 j R- C6HS j R' •• C6H4(CH3)(Orthb).

[MoOa (p.TPTB )2] Cli j·R - C6 H4 (C H3)(Pilra) j R = C6 Hs

ha ving d2sp3 hybridization. Griffith and Wickinsl''have assigned a structure for Mo02Cl2 with chlorineatoms in cis positions. On the basis of above datathe present compounds may be represented by thefollowing structures (I and II).

The authors are thankful to the authorities ofB.I.T.S., Pilani for providirg LCcessary facilities andto the UGC, New Delhi for the award of afellowship to one of them (K.L.M.).References1. DIXIT. S. N .• J. Indian chem, Soc .. 39 (1962). 407.2. ZADO. F .• J. inorg, nucl, Chem.• 25 (1963). 1115.3. LASZLO. ERDEY.. Gravimetric analysis. Pt II. Vol. 7

(Pergamon Press. London). 1965. 532.4. CLARKE. H. T .• A hand book of organic analysis (Edward

Arnold Ltd. London). 1965. 308.S. SUTTON, G. J., Ausi, J. Chem., 24 (1971), 919.

NotES6. YAMAGUCHI. A.. PENLAND. R. B.. MIZUSHIMA, S..

LANA, T. J., CURRAN, C. & QUALIANO, J. V., J. Am.chem, Soo., 80 (1958). 527.

7. BELLAMY. L. J.• Infrared spectra of complex molecules(John Wiley. New York), 1958. 355.

8. STEPHEN, W. 1. & TOWNSHEND. A., J. chem, Soc. (A),(1966). 166.

9. SRIVASTAVA, K. P. & AGARWAL, N. K .• Z. anorg. allg.Chem., 395 (1972), 168.

10. GOSAVI. R. K.. AGARWAL. U. & RAO. C. N. R.. J. Am.chem, Soc., 89 (1967), 235.

11. 'WELLS, A. F.. Structural inorganic chemistry (ClarendonPress, London). 1962, 387.

12. GRIFiTH. W. R. & WICKINS, T. D .. J. chem, Soc. (A).(1967), 590.

Tricyclopentadienylniobium(V) & Triindenyl-niobium(V) Dithiolates & Dithiophenolates

S. N. NIGAM

Department of Chemistry, M.M.H. College, Chaziabad

M. K. RASTOGI

Department of Chemistry, Hindu College, Delhi 110007and

R. K. MULTANI

Department of Chemistry, Delhi University, Delhi 110007

Received 19 August 1977; accepted 7 September 1977

Niobium(V) appears to be stabilized in the form ofthe tr'Icyclopentadienyl and triindenyl dithiolates anddithiophenolates. The complexes are characterizedby their elemental analyses and IR spectra. Struc-tures with -r-bonded rtngs are proposed.

IN this note we report the preparation and,characterization of hitherto unknown tricyclo-

pentadienyl niobium(V) and triindenylniobium(V)dithiol; tes and dithiophenoL tes. Organosulphurderivatives of C01,2, W3, M04, V5.6, Ce7 and Fe1•8 areknown. Niobium(V) was first stabilized by allowingniobium penta chloride to rerct with respectivethioalcohols and thiophenol in 1:2 molar ratio whendark coloured dithioalkoxy- and dithiophenoxy-niobium(V) trichlorides were respectively obtained.The three chlorine atoms in these compounds werethen replr ced by treatment with sodium cyclo-pentadienide or sodium indenide.

All the reactions were carried out in dryr.tmosphere since the compounds under study aresensitive to moisture. Niobium was estimated asNb205, carbon and hydrogen by microanalyticalmethods and sulphur wr.s estimated 2S Bc'S04'

Dithioalkoxy and dithiophenoxy-niobium(V) tri-chlorides - Sodium (0·23 g, 0·01 mole) was dissolvedin dry and freshly distilled alcohol (50 ml) and thesolution saturated with dry hydrogen sulphide gas.It was then stirred for 1 hr and warmed at 50°C.Niobium penta chloride (1·8 g, 0·0067 mole) dissolvedin dry tetrahydrofnran W8Sslowly added with cons-tant stirring to this solution. The mixture W2Sthen refluxed for 9 hr till the evolution of RCl g2Sceased. Brownish coloured solids so obtained wererepeatedly washed with pet. ether (60-80°). They

361

lND1AN J. CHEM., VOL. 16A, APRIL 1978

TABLE 1- ANALYTICALDATA OFTRICYCLOPENTADIENYLAND TRIINDENYLNIOBIUM(V)

DITHIOLATESAND DITHIOPHENOLATES

Compound Colour Found (%) (Cak.)·----- ....---

Nb S

(CSH.)3Nb(SCH3). Chocolate 24·25 16·91brown (24'34) (16'75)

(CsHs),Nb(SC.H.). Brown 22'58 15·53black (22-68) (15-61)

(C5H.)aNb(SC3H~). Brown 21-16 13'76(21'23) (13-85)

(C.H.)3Nb(SC3H~). Brown 21-10 13-93(21'23) (13'85)

(CSHS)3Nb(SC.H~). Brown 19·86 12·71black (19'95) (12'84)

(C5H.)3Nb(SC3H~). Dark 19·84 12·63black (19'95) (12-84)

(C.H5).Nb(SC.Hs). Black 18·25 12'72(18'38) (12,64)

(C9H7)3Nb(SCHa)s Brownish 17·34 11·96grey (17-48) (12'03)

(C9H7)3Nb(SC.H.)~. Red 16'52 11·34brown (16-60) (11-43)

(C9H7)3Nb(SCJH~). Dark 15'76 10·29brown (15-81) (10'45)

(C9H7)sNb(SC3H~)2 Red 15·70 10'53brown (15'81) (10,45)

(C9H7).Nb(SC.H~lz Dark 15·00 9·73brown (15'09) (9'87)

(C9H7)3Nb(SC.H~). Grey 14·98 9·94brown (15'09) (9'87)

(CgH7)3Nb(SC.H.). Brownish 14-12 9·66black (14·17) (9'75)

·Satisfactory C, H analyses have been obtained for allthe compounds.

corresponded to the formula NbCI3(5R)2 on analysis(R = CHs' C2Hs' n-C3H7' i-C3H7' n-C"Hg, i-C"Hg,

CaHIi)' d .. d l)' b' (V)Tricyclopentadienyl (an triin eny mo tum'dithioalkoxides and dithiophenoxide - Interaction be-tween sodium cyclopentadienide (or sodium indenide)and dithioalkoxy (or dithiophenoxy) niobium(V)trichloride was carried out in 3:1 molar ratio intetrahydrofuran by refiuxing the mixture for differenttime for respective thioalkoxy trichlorides. Thereaction mixture was then filtered and the solventfrom the dark coloured filtrate removed by eva-poration under reduced pressure. The ptsty residuewas extracted with pet. ether (60-80°) when diffe-rent brown-coloured complexes were obtained.

All the complexes (Table 1) are brown to darkbrown in colour and sensitive to moisture exceptthe dithiophenoxides. They are stable in inert anddry atmospheres. They possess disagreable odour.They are non-volatile and decompose withoutmelting. They are soluble in common organicsolvents like benzene, acetone, tetrahydrofuran,etc. but are insoluble in water. They get hydro-lysed on heating with water or on treatment withhot dil. acids and alka lis. Colour and analyticaldata of the compounds a re given in Ta ble 1. Thecompounds are monomeric 2S reves led by molecularweight determination (cryoscopically).

362

The presence of cyclopentadienyl and indenylgroup in these complexes is indicated by their usualpeaks in the IR spectra (KBr) of the compoundss.w,The absence of bands ",,2600-2550 crrr+ indicatesthe absence of free thiol or thiophenol group. Thusthe thiol and thiophenol groups are involved in < ndhave entered into coordination. The presence ofmethyl group is indicated by its vC-H ",,2959-2900,ethyl group by its C-CH3 asymmetric deformation,.....,1460and ",,1370 crrr<. The isopropyl group isdistinguished by the presence of a band in the range1385-1365 crrr? due to CH3 symmetric deformations,two bands in the region 1170-1140 and a charac-teristic band ",,820 and the presence of a band inthe region 1010-950 crrr! characterizes the isobutylgroup-'.

The \lC-5 generally appears 8S a weak or moderateintensity band in the r..r.gc 720-580 crrr '. Howeversome difficulty is experienced in recognizing it dueto the presence of inter.se C-H out-of-plane defor-mation band in this region. The v-Nb-S bandsare observed in some of these complexes in the region500-450 cm! (ref. 12). Proba bly the cyclopen-tadienyl rings are canted and remain deloca lized-e-bonded to the niobium atom 3S is indicated bythe presence of medium broad bands around 820em? (ref. 9).

References1. KING, R. B., J. Am. chem, Soc., 85 (1963), 1587.2. KING, R. B., TREICHEL, P. M. & STONE, F. G. A., J.

Am. chem, Soc., 83 (1961), 3600.3. HOLM, R. H., KING, R. B. & STONE, F. G. A., Inorg.

Chem., 2 (1963), 219.4. TREICHEL, P. M., MORRIS, J. M. & STONE, F. G. A.,

J. chem. Soc., (1963), 219.5. KING, R. B., Inorg, Chem.; 2 (1963), 641.6. HElBER, W. & BECK, W., Z. anorg, Chem., 305 (1960),

265.7. KAPOOR, S., Ph.D. thesis, University of Delhi, 1973.8. MANUEL, T. A., STAFFORD, S. L. & STONE, F. G. A.,

J. Am. chem. Soc., 83 (1961), 3597.9. FRITZ, H. P., Adv. organometal. Chem., 1 (1964), 279.

10. SCHARF, G. W. & BROWN, R. K., Can. J. Chem., 38(1960), 697.

11. RAO, C. N. R., Chemical applications of infrared spectre-scopy (Academic Press, London), 1963, 139, 269, 297.

12. MULLER,A., KREBS, B., KEBACIOGEN,R., STOCKBURGER,M. & GLEMSER, 0., Spectrochem. Acta, 24B(1968),1331.

Dicyclopentadienylnio biu m(V) & Diindenyl-niobium(V) Trialkoxides

S. N. NIGAMDepartment of Chemistry, M.M.H. College, Ghaziabad

M. K. RASTOGIDepartment of Chemistry, Hindu College, Delhi 110007

andR. K. MULTANI

Department of Chemistry, Delhi University, Delhi 110007

Received 19 August 1977; accepted 7 September 1977

Some new complexes of dicyclopentadienyl anddiindenyl derivatives of niobium(V) trialkoxides ofgeneral formula (1t-D).Nb(OR)s [D = cyclopentadienyl