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University of Illinois UNIVERSITY OF ILLINOIS THIS IS TO CERTIFY THAT THE THESIS PREPARED UNDER MY SUPERVISION BY ..... M < c h C IS ENTITLED............. .................................CMAcj C . ' Z o + i 'c , ... £ f ... t r j -Cs-H * £ § ± IIU l_ U <)J3$U IS APPROVED BY ME AS FULFILLING THIS PART OF THE REQUIREMENTS FOR THE DEGREE OF.............£>?.£h.«(®.£ ......... .................................. Ol*4 SYNTHESIS AND CHARACTERISATION OF (f|-C5Me4Et)Ru(CO)?SH BY NANCY ELLEN NICHOLS THESIS for the DECREE OF BACHELOR OF SCIENCE IN CHEMISTRY College of Liberal Arte end Soienoea University of Illinois Urbanei Illinois 1986 % V TABLE OF CONTENTS I* Introduction ........... References ........... 9 H . Chapter 1: Synthesis of (iJ-Cj^EtjRuf C0)?3H 8 Results 9 Disoussion ...... .. 11 Experimental 14 References 17 Tables iQ Figures .......... 1 1 1 . Chapter ?t Reactions of (i^-Cji^EtjRufCO^SH .......,...2 5 Results ##26 Disoussion 32 Experimental 34 References 37 Tables 39 Figures 40 INTRODUCTION Hydrodesulfurisation (HDS) is an important catalytic procaas used in tha purification of patrolaum products. [1,2] This procsss involves tha hydroganolysis of organosulfur compounds ss shown in tha equations below. [3] RSH + Ha— _ » RH + HaS RSR + 2 Hg---- » 2RH ♦ Ha 8 R88R + 3Ha— *2RH + 2Ha& Interestingly, it has been found that the types of compounds which have high HDS activity are transition metal sulfides. In addition, measurements of the catalytic activity of a series of transition metal sulfides have shown that the ability of a particular sulfide to catalyse the HOB reaction is related to the position of the transition metal in the periodic table. [4] In particular, studies indicate that first row transition metal sulfides are relatively inactive, while the seoond and third row transition metals show maximum activity with ruthenium and osmium. (SI The mechanism by which the hydrodesulfurisation reaction occurs is not fully understood, end extensive research has boon devoted to this area. Nany who have etudied the hydroganolysis of thiophene have proposed that tha mechanism involves two types of sites on the surface of the sulfided catalyst. The first is a coordination vacancy on the metal ion where the organosulfur compound may interact with the metal. The second type of sites are the surface sulfide ligands which have been proposed to react with B2 to form hydrosulfido ligands. Finally, it has been suggested that carbon-sulfur bond rupture and hydrogen atom transfer occurs between the species adsorbed on these sites. (3] The possibility that a metallothiol complex may be part of the HD6 mechanism has generated much interest in these types of compounds. Over the past decade, many of these N-SB complexes have been synthesised and the reactivity of the -SB ligand studied. Several of these will be discussed in the following paragraphs. Salts of N(C0)5<SB)- , Na Cr, Mo, or W, are an interesting group of metallothiols prepared by the direct reaction of M(CO)g with I(Fh3P)2MJ[SH] (6]. Studies of these complexes have revealed that the ooordinated SB- group la indeed reactive. For example, W(CO)5 (SB)- reacts at room temperature with acetic anhydride to give the corresponding thioacetate complex in SSI yield after 30 minutes [S]. (N(CO)s(SB)]- + (MeCO)20— > tMeC(aO)SM(CO)5]- + MeCOgB It reacts analogously with 2,4- dinitrophenyl acetate to again give lNeC(*0)8W(C0)5]- . M(CO)j(8B)- has also been found to reaot rapidly with ketones, in the presence of acid catalyst te give 3 thick*ton* complexes according to th* aquationt [6] W(CO)5 (8H)- + R2O 0 + 2CP38O3H-- >W(CO)5(8-CR2) + H20 + CF3SO3- Th* ft- -dithiol (/<.-HS)2Fe2(CO)g is another metallothiol which has b**n *xt*nslv*ly studied. This complex is prepared by 1- first reducing ^-S2)F*2(CO)( to th* [(y^-S2)P*2(CO)*! anion. This dianion can then be protonated with trifluoroaeetic acid to give (fK -B8)2P*2 (CO)g. What is interesting about this complex is that th* SB function adds to <*,fi unsaturated substrates as illustrated in th* equation below1 (7] 2 ----- >(OC) 3P*2 > # (CO) 3 piperadin* (Y> C02CB3, C(0)CH3CW) Molybdenum complexes with th* formulation [(CH3)nC3H3.n- Mo(8)(8H))2 n- 0,1,5 are noteworthy due to their catalytic properties. It haa been found that thea* complexes eatalys* the reduction of elemental sulfur to hydrogen sulfide at remarkably mild conditions (1-3 atm. l2, 75*0. These hydrosulfido complexes are also interesting in that they too roaet with unsaturated moleculest(3] 4 R [N«nCpN0(«)8B]2 + RC-CR— ♦Ren ► CpNen ♦ Hj R R R R [MenCpNo(8 )88)2 + 2C«C > «*nC CpR«n R R •kill other N-fl ooapounds that should bo aentionsd oro [<Cl3)jR]2(CO)3*n8B and [(€83)38)2(CO)3ReBB vhioh roaot with tho eoaplexes It (CO) 4 (N ■ Cr, No, *) to fora the SB bridged, alsod aotal eoaplexes [ (CI3) 3PI2 (COsB-SB-H''(CO)s (•]. Of equal internet are Cp2Ti(M)2, vhioh haa boon roaetad with (C7l|)No(00)4 to fora the biaotallio ooaplex Cp2ti- ( -M) 2No (CO)4 {»), and Cp2*(BR)2 vhioh baa boon found to react in a vary interesting way with [Pd(Ci3MC)2- <dpp 1 The exaaples given above are Just a few of the aaay prepared K - M nonpouudi. Others include Rh(BB)(CO)(P(Cgls)i)2' CpNs(M) (CO)3, Cpv(M) (CO)), and (Na(M) (€0)4)2 •* are interesting in that they are prepared by the foraal insertion of 5 sulfur into s aotnl bydrid* bond. Soat aotsllothiols have boon siaply proporod by rooctions with SB- salts. Baaaplos ineludo (diphos)N(8H)2 (M« Mi, Pd) proporod froa (diphos)NCl2 and Na8H (13)l trano-(PtB(8B)(PBt3)2], synthosisod froa trans-(PtCl(B)- (PBt3)2) and NaBB [14] t M(CO)3D8H (M-Cr, No, W> D> bipy, phen) aado froa CyBgNCCOls, bipy or phen, and Na8B [15]» and CpMi- (PBuylSB, proporod froa [CpMi(PBu3)2)+Cl- and BaSB (16). Sovoral N-8B ooapounds have also boon proporod froa roactiona with 82*. A fow osaaplos of thoso ineludo Pt(Fh3P)2(M)2 aado froa roaetion of Pt(Ph3P)2Cl2 with B28 (17]1 (BhCl(B)- (88)(PPh3)2] • 2CB2CI2 aado froa BhCKPPhyh and B28 (ll]i IrCMBMBBMCO) (PPh3)2, aado froa XrCl(CO) (PPhy^ and B2B (II] I and [N(BB)L]B''h4 (L-PP3, N - Pe, Co, Mil L- np3, N> Co, Mil pps >tr is(2-diphsnylphospb inoethyl)phosphine, np3- trls(2-diphenylphosphinoethyl)aaine aado froa N(BP4)2'<fl20, B28, MaBPh4, »nd npy or PP3 (19]. It oan bo approeiatod that aetallothiols have boooao an iaportant elasa of eoordination ooapounds. Bocross of thoir possible role in the hydrodosulfurisation proooss, it is eertain they will continue to bo oatonsivoly studied. 6 BIEEUKIfi tlj Nascoth, F.E. 1978, 22, 265. [2] Schuaan, S.C.i Shallt, H. Cat. Rsv. 1970, 1 , 245. 13] Duboia, M.R.i Van Dtrvaar, n .C.i Dubois, D.L.i Haltiwangar, R.C.i Millsr, W.X. J. Aaar. Chaa. Roe. 1980, M2, 7456-61. [4] Pscararo, T.A.i Chianslli, R.R. J. Catal. 1981, fij, 430. [5] Harris, S.i Chianslli, R.R. J. Cat. 1984, Jf, 400-12. [6] Gingsrich, R.G.N.i Angalici, R.J. j, , eh— . ana. 8«pt, 2, 1979, Ml, 5604, [7] Ssyfsrth, D. i Hsndsrson, R.s. J. orgaupggfcgl ■ ChtB» 1981, 21$, C34-C36. [8] Hulloar, V.i Vahrankaop, H. Chsai. Bar. 1977, 1M» 3810-6. [9] Rauohfuss, T.B.I Ruffing, C.J. J. Organoaatal. 1985, 1, [10] Rauohfuss, T.B.I luffing, C.J. J.Ornanoaatal. 1982, 1, 400-1. [11] Gaffnay, T.R.i Ibars, J.A. inoro. ch— . 1982, 21, 2857-59. [12] Danaar, H.i Fahlhaaaar, w.p.i Liu, a .t .i Thial, G.i Back, W. ChtBU-MX^ 19*2, Ml, 1682-93. [13] Sohaidt, N.i Hoffaann, G.G.i Hollar, R. Inoro. Chia. Acta 1979, 22, L19-L29* [14] Blaoklawa, I.N.i Bbsvorth, l.A.V.i Rankin, d .n .H.i Robartson, H.I. J. chnn. anfl. Dolton Trans. 1978, 7S3. [15] Bahrana, H.i Lindnar, I.i Lahnart, G. 1970, 22, 665-76. [16] Bato^l^^Mito^^jMfakaaoto^N.i Kasuyoshi, I. [17] Sohaidt, N.i Hoffaann, O.G. 1977, 12i, CS-C8. 7 [18] Nutting, A.M.j Boyle, P.j Pignolet, L, ippfg, Cbfgj 1984, 22, 44-8. [19] Midollinl, M. t Sacoonl, L. Inoro. Ch— . 1977, Ifi, 1518. SYXTHESIS OF ( -C5Me4Bt)Ru«50)?SH imfiOSCXifitf As described preciously metal-SH complexes have become quite important in inorganic chemistry. This chapter describee the synthesis and characterisation of a new M-BH complex ty-Cglle^t) Ru (CO) 28B. 6 9 atatiLTfl Anhydrous aodiua hydrogen sulfide, • whit* hygroscopic powder, wee prepared in 76.21 yield frow sodiua ethoaide and hydrogen sulfide, using ethanol as a solvent. The aethod used was that described by Bibeck in Inaigwic. fttnttt— 111. MaSB is readily hydrolysed in aoist air to sodiua hydroxide and hydrogen sulfide. Xt can, however, be handled in air for short periods of tiae. To prevent decoaposition, the MaSB synthesised was stored in a vacuus dessieator. in this way, saaples were found to be stable for several weeks. The rutheniua hydrosulfido maples, (tl-CgNeiltJIUHCOlgMr was prepared by a aetathesis reaction between MaSI and ty~Cglle4> Bt)Ru(C0)2Br. By siaply slurrying a 30-fold excess of Ball with (t[-Cglle4Bt)ltu(CO)2Br in methanol , C^-CsNe4Bt)lt)Ru- (CO)2*1 was foraed in 74% yield. ty'CgllegBtlRu (CO) gBr + excess Ba*B-*(>'|-C5lle4lt)«u (CO) 2*1 +BaBr The new ceapound was isolated as an orange-brown seaicrystalline solid by evaporating off the aethanol, extracting the product with diohloroaethaae, filtering this solution through *1-2 bio-beads, and than evaporating off the dichloroawthane.
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