R.D. GORSICH
2436 [CONTRIBUTION FROM THE ETHYL CORPORATION,
Vol. 84
RESEARC~ AND DEVELOPMENT DEPARTMENT, BATONROUGE, LOUISIANA]
Preparation and Properties of Some Mixed Metal Carbonyl Compounds. I. Compounds Containing a Group IV Metal and Manganese or Iron BY R. D. GORSICH RECEIVED ~TOVEMBER 20, 1961 A number of mixed metal compounds of the type L , M [ M n ( C 0 ) 5 ] . where R is alkyl or aryl, M is a group IVmetal and n is 1 or 2 were prepared. Syntheses of compounds of the type R3- .X,SnMn(CO)5, where R is aryl, X is bromine or chlorine and n is 1, 2 or 3 were achieved by either halogen cleavage reactions or by redistribution reactions. The preparation and properties of the triphenylphosphine and tetraphenylcyclopentadienone adducts of ( CeH5j3SnMn(CO)r are described. The compound CsH5Fe(C0)2Sn(CeHs)rwas prepared for cornparison with some tin-manganese compounds.
Covalent compounds containing two Group I V Kt.SnC1, 4-n XaMn(C0)s + R t n S n [ M n ( C 0 ) 5 I n n S a C l ( n = 1,2j metals have been studied extensively. Little is known, however, about the chemical properties of Triphenyltinmanganese pentacarbonyl (11)) a typicovalent bimetallic compounds containing a transi- cal example, was prepared in 56% yield by this tion metal and a group IV metal, although a num- method. ber of these compounds have been synthesized. Lead-manganese compounds were conveniently The preparation of a non-ionic organometallic synthesized by the same procedure. For example, compound containing a transition metal and a (CzH&PbMn(CO)5 was formed in 76% yield Group IV metal was first reported by Hein, from a 1: 1 molar ratio of triethyllead chloride and et al.,I who obtained compounds of the type compound I in THF. Other lead-manganese [R2PbFe(C0)4I2(R is an open chain aliphatic) and compounds of the type KsPbMn(CO)5 (R = ( R ~ P b ) ~ F e ( c 0 (R ) 4 is phenyl or cyclohexyl) by CH3, C6H5) and RzPb[Mn(C0)5]2 (R = CH3, treating an appropriate R3PbOH compound with C2H5) were prepared with equal facility. All of Ca [HFe(CO)4]2. Subsequently other mixed metal the organolead and organotin halides, with the carbonyl compounds containing a Group IV metal exception of trimethyllead chloride, afforded a and a transition metal were prepared by related single reaction product when treated with comprocedures. These included compounds of the pound I. Trimethyllead chloride, prepared actype KzSn[Co(C0)4]~ (R is alkyl),2 ( C G H ~ ) S P ~ Ccording Oto the method of Heap and Summers,6 (c0)d3 and C5H5Fe(CO)2Si(CH3)3. 4,4a Tin com- gave both (CH3)3PbMn(C0)5 (111) and (CH3)2pounds of the type [R2SnFe(C0)4I2 (R is alkyl) Pb[Mn(C0)6]2(IV) in yields of 46% and 22%) have recently been prepared by a novel reaction respectively, when treated with compound I in between iron pentacarbonyl and tetraorganotin T H F in a 1: 1 molar ratio. Initially, it was suscompound^.^ In the present study a number of pected that compound I V was formed because the bimetallic compounds having tin-manganese, lead- trimethyllead chloride contained a significant manganese and tin-iron bonds were synthesized amount of dimethyllead dichloride. Analysis of for the purpose of investigating certain of their the monohalide indicated that i t contained very physical and chemical properties. hlost of the little, if any, dihalide. Another plausible explanchemical studies were made with compounds con- ation was that compound I11 redistributed during taining tin and manganese. the reaction or during work-up. This possible Synthesis.-The organic bimetallic compounds mode of reaction was disproved after heating comprepared in this work are listed in Table I. These pound 111 a t 83" and in refluxing T H F without mixed metal carbonyl compounds were obtained by forming compound IV. treating the sodium salt of a metal carbonyl or A compound containing a silicon-manganese a cyclopentadienylmetal carbonyl compound with bond, (C6H5)3Sihfn(C0)5,was obtained from the a Group IV organometallic halide. Thus, bi- reaction of chlorotriphenylsilane with compound metallic compounds of manganese and tin were pre- I in THF. The scarlet crystals oxidized in air to pared by treating a R2SnC12or a R3SnC1compound give manganese carbonyl, hexaphenyldisiloxane with an equivalent amount of NaMn(CO)5 (I) and a small amount of triphenylsilanol. The in tetrahydrofuran (THF). The reactions pro- silicon-manganese bond is less oxidatively stable ceeded smoothly in T H F to give compounds of the than analogous tin-manganese and lead-mangatype R3SnMn(CO)5 or R2Sn[Mn(C0)5]2 in yields nese bonds. This decreased stability of the ranging from 81 to 86%. silicon manganese bond is not too surprising since the only other compound containing a transition (1) F. Hein, H. Pobloth and E. Heuser. 2 . Anorg. t i . A i l g e i n . C h r i i ? , . 248, a4 (1941); a49, 293 ( 1 9 ~ ; a54, 138 (1947); ass, 126 metal bonded to silicon, C5H5Fe( C O ) 8(CH3)3, (1948). also is quite air-sensiti~e.~ (2) W.Hieber a n d R . Breu, Chrnz. Ber., 90, 1270 (1957). In addition to the compounds with tin-manga( 3 ) F . Hein, P. Kleinert a n d W.Jehu, Naluvwisseschafkn, 44, 34 nese bonds, a bimetallic compound with tin bonded (1957). (4) T. S. Piper, 0 . Lema1 and G . Wilkinson, ibid.. 4 9 , 139 (1956). to iron, CsH5Fe(CO)zSn(C&)~(v),was prepared (4a) I n a paper to be published shortly, Dr. Dietmar Seyferth and for comparison with some of the tin-manganese his co-workers describe t h e preparation of triphenylgermyl-n-cycloorganometallic compounds. This carbonyl compentadienyliron dicarbonyl and triphenylgermylmanganese pentapound was readily obtained by treating triphenylcarbonyl. Both of these compoLinds are significantly more nir-stable t h a n t h e silicon analogs. tin chloride with CsHbFe(C0)nNa in THF.
+
(5) R . B. King and F . G. A . Stone,
(ISGO).
J . An,. Cheni. SOL.,82, 3833 ),I(
R . H e a p and B C. Summers, J . CheJJf. S O L . , 2983 (1919).
July 5 , 1962
COMPOUNDS WITH GROUPI V METALS A N D X~NGASESE OR IRON
2157
TABLE I MIXEDMETALCOMPOUNDS' Crystallization solvent
Formulab
( C B H S ) ~ S ~ M ~ ((11) CO)~ (X) (C&L)3Sn[Mn(C0)~12 Me& [Mn(CO)sll ( X I ) (C ~ H b h P b M n ( c 0 ) ~ EtAPb[Mn(CO)J? Et,PbMn( C0)s
%-Hexane n-Hexane n-Hexane %-Hexane n-Hexane Sone
Me8PbMn(CO)sd (111) Pet. ether Pet. ether MezPb[Mn(CO)s]2' ( I V ) V )~ Ethanol c p F e ( c 0 ) ~ S n c ~( H (C6Hb)3SnMn(CO)4P(C6H6)3' (VI) Ethanol-benzene ( c ~ H s ) ~ S n MCO)dAs( n( '&Ha): Ethanol-benzene
Yield,
%
81 82 86 79 68 76
Melting point, OC.
47" 23" 39 94 42
148-150 137-139 102-104 146-148 i7-79 (B.p. 70-73, 0.1 mm.) 30-31 108-110 139-141 228-230 222-224
30
225-207
Color
Analyses Calcd. Found C H C
H
White White Pale yellow Yellow Orange Yellow
50.69 39.86 26.75 43.60 25.66 27.00
2.92 1.81 1.12 2.39 1.54 3.09
50.90 39.83 26.85 44.25 25.81 27.40
2.87 1.68 1.19 2.59 1.61 3.18
Yellow Orange Orange V'hite White
21.48 22.98
2.03 0.96
21.35 23.03
1.97 0.99
61.65 58.35
3.88 3.67
61.85 58.84
3.88 3.71
Yellow
68.75
4.04
68.56
4.10
All but three compounds were obtained by treating a Group I V alkyl- or arylmetal halide with the sodium derivative of a transition metal carbonyl in THF. Compounds VIII, VI and the arsenic analog of VI were obtained via carbonyl Calcd.: Mn, displacement reactions on 11. * Cp = cyclopentadienyl; CsHj = phenyl; Me = methyl; E t = ethyl. 10.1; Sn, 21.78; mol. wt,, 544. Found: M n , 9.9; Sn, 21.88; mol. wt., 539. Calcd.: Pb, 46.33. Found: Pb, 46.42. Yield based on h'aMn(C0)s. Calcd.: Pb, 33.04. Found: Pb, 33.10. 0 Calcd.: P, 4.0; mol, wt., 779. Found: P, 4.2; mol. w t . , 726. Calcd.: Mn, 6.67. Found: Mn, 6.96.
'
CsHbFe(C0)2Ka4- (C6H5)7SnC1--f CaHsFe(c o ) ~ S nC6H5)J ( T-
Properties.-All
+ sac1
of the mixed metal compounds
in Table I , except (C2H5)oPbMn(C0)5,are solids a t 25" and range in color from deep orange for the
trum of compound I1 as a KBr disk showed only terminal manganese-carbonyl stretching frequencies a t 4.78 p and 5.03 p.8 If indeed the carbonyl groups were involved in bridging, a pronounced shift of the manganese-carbonyl stretching frequency to a higher wave length certainly would have been e ~ p e c t e d . ~ Chemical Reactions-Although most known reactions of metal carbonyls involve substitution of the carbonyl grouping, three sites in the mixed metal carbonyl compounds are subject to attack by either electrophilic, nucleophilic or neutral chemical reagents. Thus, in compounds of the type K3SIMn(C0)5or R2M [Mn(C0)5]2,the carbonmetal, metal-metal or metal-carbonyl linkages are potential points of chemical reaction. Carbon monoxide can be displaced from metal carbonyls with varying ease by compounds such a s triphenylphosphine either thermally or catalytically (ultraviolet).lo When carbonyl compound I1 was heated with excess triphenylphosphine a t about 195' in the absence of a solvent and under a nitrogen atmosphere, (C6H5)3SnMn(C0)4P(C&5)3 (VI), was obtained in 94y0 yield.
tin-iron compound V and some lead-manganese compounds to white for most of the compounds having tin-manganese bonds. The lead-manganese compound (CsH&PbMn(CO)s is a yellow liquid which can be distilled only at reduced pressures. The tin-manganese compounds are thermally more stable than analogous lead-manganese compounds, particularly (CeH5)sSnPI1n(CO)s(11), which only begins to evolve carbon monoxide a t 195". The solids were purified by crystallization from appropriate solvents while (CH3)3PbMn(C0)5,a low melting solid, was purified by distillation a t reduced pressures. The mixed metal compounds are readily soluble in polar solvents like methylene chloride, ether, acetone and T H F ; they are fairly soluble in ethanol, benzene and other aromatic solvents and are moderately to slightly soluble in aliphatic solvents like n-hexane. The compounds listed in Table I are fairly air- (C6H6MnMn(CO), P(CsH5)a -+(ceH,)~SnMn( CO)J'( C ~ H S ) ~CO stable. All of the compounds decompose a t V I varying rates in organic solvents. Oxidation of the compounds, both in solution and in the crystal- No other substitution product was isolated under line state, seems to be accelerated by light. I n these conditions. Compound VI is diamagnetic general, oxidative stability of the metal-metal (7) The suggestion has been made t h a t carbonyl bridging exists in bond in compounds of the type (CeH5)3MMn- the compound ( C d H h S n [Co(CO)aP(CsHa)a]r; however, no structural (CO)5, where M is a Group I V metal, is Sn > P b > evidence was given in support.' (8) T h e CO stretching frequencies are very similar t o those reported Si. Also, as the number of Mn(C0)b groupings CHsMn(C0)a: 4.8 p , 5.0 p and 5.1 p [R. D. Closson, J. Kozikowski in the bimetallic compounds increases, e.g., (CG- for and T. H . Coffield, J. Org. Chem., 22, 595 (1957)j and for ClMn(C0)b; H5)&3n [Mn(C0)5]2, the oxidative stability de- 4.53 p and 4.96p [E. W. Abel and G. Wilkinson, J . Chem. Soc., 1501 creases. (1959)l. (9) J. C h a t t , P. L. Pauson, and L. M. Venanzi. "Organometallic The infrared spectra of metal carbonyl comChemistry." Ed. by H. Zeiss, Rcinhold Publishing Corp., New York, pounds having tin-manganese, lead-manganese or S . Y.,1960, p. 478. tin-iron bonds did not exhibit absorption bands (10) A general discussion of this type of substitution reaction is characteristic of CO bri~lging.~The infrared spec- given in ref. 9, p . 484.
+
+
R . D . GORSICII
2488
and melts without carbon monoxide evolution. The corresponding arsine derivative, (CsHs)YS n i V h ( C 0 ) ~ s ( C 6 H ~ was ) 3 , prepared in a similar fashion. Compound VI was unambiguously synthesized by treating triphenyltin chloride with NaMn(C0)4P(C8H6)s.11
+
( C b H s ) s S ~ ~fC IS:IN~(CO)~IJ(C~~~~).~ -----f \'t SaCl
Cntil recently no manganese carbonyl derivative containing a x-bonded olefin or diene ligand in which the organic moiety effectively contributed an even number of electrons to the central metal atom was reported.'? \Yeiss and HiibelI3 showed that treatment of lfn?(CO)lo with tetraphenylcyclopentadienone in an inert solvent afforded an unstable intermediate which, after hydrolysis, gave the cyclopentadienyl derivative, compound VII. Apparently an unstable intermediate is formed which is stabilized after hydrolysis by forming the well-known "sandwich" type of cyclopentadienyl derivative in which the cyclopentadienyl moiety effectively contributes five electrons to the central manganese atom. Since the tinmanganese bond in compound I1 is thermally stable, i t should be possible to thermally displace carbon monoxide from compound I1 by a hydrocarbon ligand to give a derivative in which the x bonded ligand contributes an even number of electrons to manganese. This type of a-bonded complex, compound VIII, was obtained in 317, yield by heating a mixture of compound I1 and tetraphenylcyclopentadienone (1 : 1 molar ratio) between 180 and 194" for -1 hr. in the absence of a solvent and under a nitrogen atmosphere. Slthough crystals of compound VI11 apparently are insensitive to air, a benzene solution of the material gradually turns deep red. Elemental OH
i701. 84
Halogen Derivatives,-- The reactions of bimetallic compounds, particularly those containing a tin-manganese bond, with electrophilic reagents such as halogen or hydrogen chloride can occur at either of two sites. The tin-manganese bond can be broken, or the organic moieties attached to tin can be totally or selectively cleaved. The point of attack in a tin-manganese compound by ;I specific electrophilic reagent is dependent on the type of organic radical attached to tin and on the number of 1hico)5 groups in the bimetallic compound. Excess chlorine in carbon tetrachloride a t 25' ruptured the three phenyl-tin bonds in compound I1 to give Cl$31i\ln(CO)~(IX) and chlorobenzene iCsHj)&1Mn(C0),f 3 C 1 --+C l k h M n ( C 0 ) s I
.\
+ 3CaHaC1
however, resistance of the tin-manganese bond in compound IX to further attack by chlorine was unexpected. Initially, it was thought that further reaction with chlorine did not occur because of the low solubility of compound I X in carbon tetrachloride. This was disproved by treating compound I1 with excess chlorine in methylene chloride, a solvent in which compound I X is soluble; again, compound I X was the only product isolated. Compound I X is a white solid which is sensitive to moisture and which decomposes sharply a t 168" without melting. The bromo analog, BraSnMn(CO)5, was obtained by treating compound I1 with excess bromine in carbon tetrachloride either a t ambient temperature or at reflux temperature. Even at reflux temperature there was no indication of the tin-manganese bond being broken by bromine. X halogen derivative related to compound I X , C ~ & I , \ I ~ ( C O ) ~ P ( C ~was H ~ )prepared ~, in 64% yield from the non-halogen derivative (VI) and chlorine in methylene chloride. (C
~H~),~S~M~(CO)~ f P3Cll ( C ~---f HS)~ 1-1
ClsSnMn(CO)4P(C&;,)af 3CeHsCl
VI1
(C,H,),Sn
(CO);
VI11
analysis and a molecular weight measurement support the assigned structure for VIII. The infrared spectrum showed absorption bands characteristic of terminal manganese-carbonyl bonds. An absorption band characteristic of the carbonyl grouping in the organic moiety appeared a t 6.25 /A.
(11) An elegant method for preparing Na>ln(C,O)rP(CaHs)a mas recently described by W. Hieber, G. Faulhaber and F. Theubert, %. Salnrfoovsch., lSb, 326 (1960). (12) An ethylene complex of CsHsMn(CO)a, CaHshln(CO)?C?Ha, was prrpared recently by a reaction between CsHsMn(C0)a and ethylene which was catalyzed by ultraviolet light; H. P. K6gler and E. 0. Fischer, Z . S a t ~ ~ h ' s ~ lhl .b, , 676 (1960). In addition, a r-allyl derivative of manganese, CaHehln(CO)4, in which t h e organic moiety effectively contributes three electrons t o t h e central a t o m has been prepared: H. D . Kaesz. R . B. King and F. G. A. Stone, i b i d . , l S b , 682 (1960). Also, see W. R . XlcClellean, H. H . Hoehn, H. S . Cripps, E. L. Muetterties and B . W. Hawk, J . A m . Chem SOL,83,1601 (1961). (IS) E Weiss and W. Huhel, J. Iwurg. and Suciear C h e m . , 11, 4 2 (1HRQ). (14) T h e infrared spectra of a numbar of tetraphenylcyclopentadicnone derivatives of iron, cobalt and molybdenum carbonyls have a
Compounds of the type R2Sn[Mn(CO),]2 gaVe different cleavage products with electrophilic reagents, depending on the electrophile. When (C6H&Sn [r\h~(CO)~]z (X) was treated with hydrogen chloride, products were obtained that were different from those isolated when chlorine was used. Thus, chlorine attacked compound X to give compound IX, chlorobenzene and Clr\
