Bhoon, Yudhvir K.

Majer, J. R.

English

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Thanks are due to the Head of the Chemistryand Physics Departments of the Lucknow Universityfor providing laboratory facilities and to the StateCSIR, Lucknow, and the CSIR, New Delhi, forfinancial assistance.References1. MALTESTA, M., Gaze. cliim, ital., 70 (1940), 533.2. THORN, G. D. & LUDWIG, R A., Dithiocarbamates andrelated compounds (Elsevier, New York), 1962, 48.3. I3HAT, A. N., FAY, R C., LEWIS, D. F., LINDMARK,A. F. & STRAUS, S. H., Inorg, Chem., 13 (1974), 886.4. BONATI, F., CEINI, S. & UGO, H.., I organometal. Chem.,9 (1967), 395.5. BONATI, F. & UGO, H.,I organometal. cu-«, 10 (1967), 257.6. SRIVASTAVA, T. N. & KUMAR, VIJAY, I organometal.Chern., 107 (1976), 55.7. GUGGENHEIM, E. A., Trans. Faraday Soc., 45 (1949), 715.8. GUVYANOVA, E. N. & KOZIMA, L. S., Z. Fiz. Khirn.,30 (1956), 616; Chem. Abstr., 50 (1956), 14292b.9. GUPTA, R & l\IAJEE, B., I organometal, Chem., 33(1971), 169.10. VAN DE VONDEL, D. F. & VANDER KELN, G. P., Iorganometal. Chem., 55 (1973), 85.11. BENT, H. A., I inorg. nucl. Chem., 19 (1961), 43.12. BERGMANN, E. & SCHUTZ, W., Z. phys. Chem., B19(1932), 401; HEIN, F. & KALMEYER, H., Z. anorg. allg.Chem., 311 (1961), 260.13. PIERCE, L. & PETERSON, D. H., I chem. Phys., 33(1960), 907.14. MOORE, F. W. & RICE, R F., Inorg, Chem., 7 (1968),2510.Mass Spectral Studies of1-(2'-Pyridylazo)-2-phenanthrol & of ItsChelates with Cu(II), Co(II), Co(III) & V(V)YUDHVIR K. 13HOON'Department of Chemistry, Sri Venkatoswara CollegeDhaula Kuan, New Delhi 110021andJ. R. MAJERDepartment of Chemistry, University of BirminghamBirminghamReceived 7 March )977; accepted 10 May 1977Mass spectra of l_(l'_pyridylazo)-l-phenanthrol(PAPL) and its metal chelates with V(V), Co(III) andCu(II) have been reported. The novel feature asso-ciated with the spectrum of V(V) complex is the exist-ence of the species V(PAPL)~' due to the reduction ofV(V) to V(II). Peaks coerespondtng to the differentisotopes of the metal have also been observed in thefral1mentation pattern.TRIDENT ATE complexing agents containing anazo group, a heterocyclic nitrogen atom anda hydr?xyl group ortho to the azo gro~~ have beenextensively used as spectrophotometric and c?m-plexing agents in the micro-determlllatlOn of vanousmetal ions. 1-\2'-P{Tidylazo)-2-phena~throl.(PtPL)is a newly synthesized member of this serres andhas recently been used as a spectrophotometricreagent for (0(II)3, UOz(II)4, ~t(I~)5 and ~s(VIII)6,as visual indicator in EDT A t itratrons and Its metalchelates have found use as acid-base indicators".The chelates of PAPL with 3d-transition metal*To whom a.ll correspondence should be made.NOTESions9-12 have been prepared recently by the authorand chracterized by magnetic susceptibility measure-ments from room temperature to liquid nitrogentemperature, EPR and IR spectral studies. Wedescribe here the results of our investig-ations onthe mass spectral studies on V(V), Co(11), Co(III)and CUlII) chelates of PAPL.The fragmentation pattern vi PAPL is shown inChart 1. The fragmentation pattern si.pports theenol form of the molecule as confirmed bv Nl\1H.spectrum taken in CDCla which shows a signal at15·28 ppm in the off field due to the phenolic -OHgroup and not the keto form.The mass spectrum of PAPL shows the molecularion as a strong peak at m/e 299, which fragmentsby the loss of nitrogen to give rise to ion (b) atmlc 271 which further loses hydrogen to give theion (e) at 270.The ion (a) may give the neutral molecule (d)and the ion (e) (m/e 152) in which the two benzenerings are linked by a four-membered ring. Theion (e) loses CO molecule to give ion (j) (m/e 242)which undergoes fragmentation by two differentpathways to give rise to pyridine (m/e 78) and theion (g) (m/e 165). A peak at m.'e 51 confirms theloss of HCN from pyridine ion.Vanadium-PAPL complex-:« Vanadium has twonaturally occurring isotopes with the following massesand abundance: 51 (99'76) and 50 (0,24). Asreported by us earlier", we obtained the complexof VlV) of the compositicn V02(PAPL).H20. Themass spectrum of the complex exhibits peaks atmle 399 and 398 corresponding to the molccul r ionscontaining sOVand Sly. The presence of thesepeaks also confirms the coordination of water mole-cule to vanadium. The spectrum shows two peaksat m/~ 647 and 646 which may possibly be due tothe ion V(PAPL)2]+' where vanadium is in the +2oxidation state, resulting from the reduction ofV(V) to VeIl) but it does not seem to rndergo fur-ther fragmentation. Similarly, ions VO(PAPL) H20j++.CHART I1019INDIAN J. CHEM., VOL. 15A, NOVEMBER 1977and VO(PAPL)]+ also appear in the spectrumresulting from the molecular ion as a remit ofreduction of V(V) to V(IV). The isotopic abundancealso made easy the identification of vanadium con-taining fragments in the spectrum. The majorfragmentation pattern for the complex is shown inChart 2.Copper(II)-PAPL complex - The most abundantisotopes of copper are 65CU (60·09%) and 63CU(30·99%). The elemental analysis of the chelate-?corresponds to Cu(PAPL)Cl and correspondinglythe spectrum shows the parent peaks at m]e 396and 398; the existence of the doublet confirms theisotopic abunclar;ce of the two isotopes of c?p~erand moreover, It also demonstrates the stoichio-met~v in the chelate to be 1:1 (metal-ligand).The parent ion loses chlorine which also occurs intwo abundant isotopes 35Cl and 37C1. The lossof 35Cl and 37Clfrom molecular ion at ni]» 396 and398 is expected to give rise to only one peak atmle 361 and the fame is confirmed by the appear-ance of a peak at m]e 361 which loses the ligand.The ligand then undergoes fragmentation in thesame way as shown in Chart 1.Cobalt(II) and cobalt(III) complexes - We havechosen both cobalt(II) and cobalt(III) chelates forthe mass spectral studies. 'vVehave earlier reportedthe results of our investigations on the magneticsusceptibility measurements'! from room tempera-ture to liquid nitrogen on the two coba1t(II) com-plexes of PAPL (gre~n and pink) prepared ur:derinert atmosphere of mtrogen to prevent the oxida-tion of Co(II) to Co(III). The green complex ofcomposition Co(PAPL)2.4C2H~OH sho:ved antife:-ro-magnetic exchange interactions while the pink-col~ured complex- with composition Co(PAPL)2.-4C2H50H.lCHCJ3 was found to have spin ~t~teequilibrium between 4T2g an~ 2E states characterizingthe high-spin and low-spin states of co~a1t(II).We now report the results of mass spectral investi-gations carried on those complexes,. and the CO?~1t-(III) chelates which have the chemical cornpositir.n[Co(PAPL)2CIJ. and [Co(PAPL)2J.Br.Cobalt occurs only as one isotope, i.e. 59CO(100%).Since the cthanoijchioroform molecules in grew andpink complexes are present only as molecules ofsolvent of crystallization, at thet ernperature of recor-ding the mass spectrum, these solvent molecules areexpected to be lost and correspondingly Co(PAPL)2will give the molecular ion and in the mass spectrumof both the complexes, the molecular ion appearsat mle 655 which loses the ligand residue to givea peak at m/e 357 and the ligand residu('. undergoesfragmentation in the same way as shown In Chart I.Amongst the cobalt(III) complexes, we havechosen Co(PAPL)2.Cl and Co(PAPL\.Br and fromthe conductance measurements, it has been estab-Iished that both the complexes are 1:1 electrolytesand hence the Cl and Br are in the outer sphere ofcoordination. From the mass spectral studiespoint of view, both the complexes shoul~ give riseto molecular ions at m]» 655 corresponding to Co-(PAPL); and in fact in the mass spectrum of boththe chelates, parent peaks have been obtained atm/e 655. In the spectrum of Co(PAPL)2.Cl, the1020+. :f-.399,398'0,C» 0'1."" II.».'N ()68365,364+CHART 2molecular ion loses one ligand molecule and finallythe ligand undergoes fragmentation as discussedearlier. But in the spectrum of Co(PAPL)2,Br,the peak at m/e 436 is also observed and may poss-ibly correspond to Co(PAPL)BrJ+ and the oxidationstate of cobalt seems to be. +3 since Br has to bebonded to the cobalt in the inner coordinationsphere, The further fragmentation pattern is thesame as has been observed in other cases.The work was carried out under the scheme"Financial assistance to science teachers" of theUGC, New Delhi.References1. SHIBATA, S., in Chclatcs in analytical chemistry, Vol.IV.edited by H. A. Flaschka & A. J. Barnard Or) (MarcelDekker. New York). 1972.2. CHISWELL, B., LIONS, F. & TOMILSON, Inorg. Chem., 3(1964), 492.3. RISHl, A. K., GARG, B. S. & SINGH, R. P., Indian J.cs-«, 10 (1972), 1037.4. RISHl, A. K, GARG, B. S. & SINGH, R. P., Curro su.,41 (1972), 155.5. BHOON, Y. K., PANDEYA, K. B. & SINGH, R. P., Chi mia ,28 (1974). 659.6. BHOON, Y. K., PANDEYA, K. D. & SINGH, R. P., Ann.cu,«, 65 (1975), 735.7. BHOON, Y. K., PANDEYA, K. D. & SINGH, R. P., CurroSci., 43 (1974), 306.8. BHOON, Y. K., PANDEYA, K. B. & SINGH. R. P,I Indianchem: Soc., 51 (1974), 960.9. BHOON, Y. K., PANDEYA, K. B. & SINGH, R. P., IndianI cu«; 14A (1976), 681.10. BHOON, Y. K, PANDEYA, K B. & SINGH, R. P., J. coord.cu,«, 6 (1976), 71.11. BHOON, Y. K., PANDEYA. K B. & SINGH, R. P., IndianJ. Che1l/., 14A (1976). 907.12. BHOON, Y. K, PANDEYA, K. B. & SINGH, R. P., Ann.cu«; (1977). (in press).13. BETTERIDGE, D. & JOHN, D., Analyst, 98 (1973), 377.14. BHOON, Y. K, PANDEYA, K B. & SINGH, R. P., IndianJ. Chem., 13 (1975), 84.

Mass Spectral Studies of 1-(2'-Pyridylazo)-2-phenanthrol & of Its Chelates with Cu(II), Co(II), Co(III) & V(V)

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Mass Spectral Studies of 1-(2'-Pyridylazo)-2-phenanthrol & of Its Chelates with Cu(II), Co(II), Co(III) & V(V)

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