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Distribution of Terminal and Bridging CO-Groups in an Anionic Carbonylmetal Cluster as a Result of Ion-Pair Formation. Crystal and Molecular Structure of LiCo3(CO)10 ╖ i-Pr2O

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Experimental
The method essentially involves the deposition of the three
chosen metals into a thin, viscous film of a functionalized liquid polymer at close to room temperature. The creation of
the distinct, polymer-anchored metal sites is conveniently
monitored by means of UV-visible spectroscopy of the fluid
sample adhering to a quartz optical window attached to the
second stage of a Displex closed-cycle helium refrigeration
system. The vacuum furnace employed for these trimetal vapor experiments has not been previously described but is a
straightforward modification of the arrangement used for
our earlier bimetal vapor work"]. The device consisted of a
water-cooled, four-electrode-flange assembly (illustrated be-
t
i;,
B
low) having a triangular electrode configuration of live terminals (A, B, C) around a central ground terminal (D). The
three different evaporation sources were connected radially
(A-D, B-D, C-D) and heated directly and independently
by passage of AC. The rate of deposition of the metals was
monitored by three in situ quartz crystal microbalances[xlaligned behind each metal vapor source. Radiation shields
were appropriately positioned between the evaporation
sources, liquid polymer sample, and quartz crystals. The
geometrical correction factor for this trimetal deposition configuration was determined by replacing the sample window
by a fourth mass monitor, thereby permitting a calibration of
the forward-to-backward flux for each metal. Chromium metal was vaporized from a tantalum Knudsen cell (wall thickness 0.010", orifice diameter 0.020") while vanadium and titanium metal depositions were achieved from thin (0.015")
filaments of the metal. All metals were better than 99.95% as
supplied by A. D. McKay, New York.
Distribution of Terminal and Bridging CO-Groups
in an Anionic Carbonylrnetal Cluster as a Result of
Ion-Pair Formation. Crystal and Molecular Structure
of LiCo3(CO),o.i-Pr,O[**]
By Hans-Norbert Adams, Giuseppe Fachinetti, and Joachim
Strahle[*l
The interaction between highly acidic countercations and
carbonyl groups of mononuclear carbonylmetalates in solvents of relatively poor coordinating ability has already been
demonstrated"], and examples are also known of interactions
of this sort in the solid state[*]. The increased reactivity of
mononuclear carbonyl metalates towards alkyl halides13"]
and molecular oxygen[3b1has been interpreted on this basis.
Anionic carbonylmetalates, however, have not been studied
under "acidic" conditions ( ie. in weakly coordinating solvents and with countercations of very high charge density),
so comparable cation-anion interactions could previously not
be observed[41.
We have now succeeded in preparing single crystals of diisopropyl ether solvated LiCo,(CO),,, as product of the reac-
c131
I
O(l-2-3)
0122-
Received- January 2, 1980 [Z 461 lE]
German version: Angew. Chem. Y2. 409 (1980)
CAS Registry numbers
Cr. 7440-47-3, TI. 7440-32-6, V, 7440-62-2
[ l ] J . H . Sinfelr, US Pat. 3953368 (April 27, 1976); Acc. Chem. Res. 10, 15
(1977). and references cited therein.
121 J. J. Burron. R. L. Gartent Advanced Materials in Catalysis Academic
Press, New York 1977, and references cited therein.
131 G. L. Geoflroy. W L. Gladfeller. J Am. Chem. SOC.YY, 304 (1977).
141 M. Ichikawa, J. Catal. 59. 67 (1979). and references cited therein.
[5] C. E. Carraher, Jr., J. E. Shears, C. U. Pilrman. Jr.: Organometallic Polymers. Academic Press, New York 1978; C. U Pittman. Jr., L. R. Smuh. J . Am.
Chem. SOC.Y7, 1749(1975); R. Pierantozzr. K. J. McQuode, B. C. Gates, M.
Wol/, H. Knuzinger, W. Ruhmann, J . Am. Chem. SOC. 101, 5436 (1979); J.
M. Basser. A . K. Smith in M Tsutui. R. Ugot Fundamental Research in Homogeneous Catalysis, Vol. 1. Plenum Press. New York 1978. and references
cited therein.
[6j C. G. Francis, H . Huber, G. A. Ozin. Inorg. Chem. /Y, 219 (19x0).
171 W. Klorzbucher. G. A. Orm, J. G. Norman, Jr.. H J Kolari, Inorg. Chem. 14.
2871 (1977).
(81 M. Moskooits, G A Orin, J . Appl. Spectrosc. 26, 487 (1972).
[9] C. G. Francis, P. L. Timms, J. Chem. SOC.Chem. Commun. 1977. 466, C. G.
Francis. P. L. Timms. J Chem. Soc Dalton Trans., in press.
[lo] C. C Francu. G. A. Ozin: Proceedings of the EUCMOS Conference. Frankfurt. September 1979, in Spectroscopy in Chemistry and Physics. Elsevier.
Amsterdam 1979; J Mol. Struct. 5Y. 55 (1980).
1111 C. G. Francis, H. Huber. G. A Ozin. J . Am Chem. SOC.101. 6250 (1979)
112) A least squares analysis was performed using the SIMPLEX optimizatton
method of J. A. Nelder and R. Mead, Computer J . 7, 308 (1965) The program used was that of D F Mclntosh and M. R. Pererson (Program 3 of
Program 342. Quantum Cheni. Program Exchange. Indiana Univ.).
404
Li'
Fig. I . Molecular structure of LiCo3(CO)tI,.i-Pr20.Some important dislances
[A] are: Co(1) Co(2) 2.489(1). Co(l) cO(3) 2.472(1), Co(2) Co(3) 2.462(1):
average Co C(termlna1) 1.800, average C O(termina1) 1.123; average
Co C(bridging) 1.956; C(1-2) O(I-2) 1.137(8); C(I-3) O(1-3) 1.164(7): C(23) O(2-3) 1.164(7); average Co C(I-2-3) 2.013. C(1-2-3) O(1-2.3) 1.190(7).
["I Prof. Dr. J . Strahle. DipLChem. H.-N. A d a m
lnstitut fur Anorganische Chemie der Universitat
Auf der Morgenstelle 18. D-7400 Tubingen (Germany)
Dr. G . Fachinetti [ ]
University of Pisa, lstituto di Chimica Generale
Via Risorgimento 35, 1-56 100 Pisa (Italy)
+
1 1 Author to whom correspondence should be addressed
I*')This work was supported by the National Research
Council (C.N.R..
Roma), and by the Deutsche Forschungsgemeinschaft. We thank Prof. Fuusro
Calderazzo for helpful discussions.
0 Verlag Chemie, GmbH. 6940 Weinheim. /980 0S70-08~~/8#jOFOS-404
S 02.50/0
Angew. Chem. In(. Ed. Engl. 19 (1980) No. 5
tion of LiCo(CO), with C O ~ ( C O ) ,The
~ ~ ~molecular
~.
structure of LiCo3(CO),o.i-Pr,0 (1) has been solved by X-ray diffraction methods161. It consists of the ions [ C O ~ ( C O ) , ~and
]Li . The cations are approximately tetrahedrally surrounded
by one ether oxygen (1.9 10( 12l A) and by three carbonyl oxygens [one p 3 - C 0 , 1.859(10) A, and two p-CO, Li -0(2-3)
1.989(10), Li 0(1-3) 2.049(10) A] of three different cluster
units.
The three cobalt atoms form an almost regular triangle,
forming the base of a tetrahedron having the face-bridging
carbon, C( 1-2-3), at a n apex. The interatomic distances and
angles of the Co,C cluster are comparable with those found
in other cluster compounds of the oxymethylidyne type['].
The IR spectrum of (1) as Nujol mull shows strong absorptions around 1800 c m- ', in agreement with the presence of
edge-bridging carbonyl groups as established by the X-ray
structure analysis. This contrasts with the weak carbonyl absorption observed a t 1865 c m - ' in ether solution'']. These
observations can be rationalized in terms of small amounts of
clusters with edge-bridging carbonyl groups in solvent-dependent equilibria with clusters containing terminal carbonyl groups only. Addition of tetrahydrofuran (1-3 vol-%) to a
n-Bu20 solution of ( I ) , before decomposition takes
considerably decreases the intensity of the 1865 c m - ' band
and modifies the spectral pattern associated with the facebridging carbonyl group at about 1580 c m - ' , while the terminal carbonyl stretching region around 2000 cm - ' remains
essentially unchanged: under these conditions the acidity of
Li supposedly is decreased through coordination to the
more basic tetrahydrofuran. In the solid state the acidity of
Li+ is greatly enhanced, thus promoting the structural
change to the form containing the edge-bridging carbonyl
groups.
Our investigations show that dramatic structural changes
can occur in an anionic carbonyl cluster by apparently small
changes of the acid-base properties of the system.
+
+
Experimental
Analytically pure LiCo3(C0),,,-E t 2 0 (1.3 g) was dissolved
in diisopropyl ether (20 ml) and the resulting solution was
concentrated to about 5 mi under reduced pressure. On addition of n-hexane (100 ml) and filtration, the mother liquor
slowly yielded 0.5 g of LiCo3(CO)Io-i-Pr20
as black crystals.
All of the operations must be carried out under purified argon.
Received: October 15. 1979 [Z 462 IE]
German version: Angew. Chem. Y2, 441 (1980)
171 B. Stuue, V. Batre/. R. Boese, G. Schmrd, Chem. Ber. / I / , 1603 (1978); Y
Barrel. Z. Naturforsch. B 31, 342 (1976); V. Batre/, U. Muller. R. Allmunn. 1.
Organomet Chem. 102, 109 (1975). C Schmrd. V. Butrel. B. Srutte. /hid 113.
67 (1976): F Ktanberg. W . B. Asken. L. J . Guggenberger. Inorg. Chem 7.
2265 (1968).
Triple-Decker Sandwich Complexes of 4d and 5d
Metals with cyclo-Triphosphorus as p,q3-Ligand
Structural and Magnetic Properties
By CIaudio Bianchini, Massimo Di Vaira, Andrea Meli,
and Luigi Sacconil"
The recent synthesis of mononuclear and dinuclear 3d metal complexes containing the cyclo-triphosphorus (q3-P3)
group as a ligand"' prompted us to attempt the synthesis of
the corresponding compounds of the 4d and 5d metals. On
reaction of white phosphorus (P4) with [Rh(C,H,),Cl], ( I ) or
Ir(PPh,),(CO)Cl in the presence of 1,1,1-tris(diphenylphosphinomethy1)ethane (triphos) we obtained the mononuclear
complexes [(triphos)M(q3-P3)] with M = Rh (2) and M = Ir
(31, respectively[21.These compounds react with (1) and cobalt(n) or nickel(i1) tetrafluoborates in the presence of triphos (and, where appropriate, of NaBPh,) yielding the dinuclear compounds
[(triph~s)Rh-~-(q~-P,)Co(triphos)](BPh,)~~
2 (CH3),C0 (4)
I(triph~s)Rh-p-(q~-P,)Ni(triphos)](BF~)~
.C4H,0 (5)
[(triph0s)Ir-p-(q~-P3)Co(triphos)](BF,)~~CH~Cl~
(6)
[(triphos)Rh-p-(q'-P,)Rh(triphos)]BPh4. (CH,),CO (7)
whose cations have a triple-decker sandwich structure with
cyclo-triphosphorus acting as central bridge-forming lrihapto
lzgand. The salts (41,(5) and (6) behave as 1 :2 electrolytes,
whereas (7) is a 1:1 electrolyte. They are all air-stable in the
solid state, but rather unstable in solution. Compounds (4)
and (6) are paramagnetic with a magnetic moment corresponding to a doublet ground state. Compound (7) is essentially diamagnetic at room temperature, whereas (S) has a
magnetic moment slightly dependent on the nature of the
counterion and of the solvent in the lattice, decreasing from
values of 1.3-1.6 F~ at room temperature to ca. 0.7 p+ at
100 K. The magnetic behavior of (5) and (7) differs considerably from that of the previously described complexes with 32
valence electrons, which have a magnetic moment corresponding to two unpaired electrons"]. This difference in the
magnetic properties may be traced to structural differences
between the compounds[31:the -q3-P3bridge in {5) is shifted
from the line joining the two metal atoms (cf. Fig. 1) in such
CAS Registry numbers.
( / I . 73612-21-2: LiCo,(CO),,,. 26748-45-3
P
[I[
121
[3J
[4]
151
16)
W F Edge//. J. Lyford. R Barberfa. C. 1. Jose. J . Am. Chem. SOC.93, 6403
(197 1 ); W. f . Edge//,J. Lyford, ibid. 93.64 (1971 ); M. Y. Darensbourg. D. J.
Darensbourg. D. Burns, D. A. Drew, rbid. 98, 3127 (1976).
G fuchinettr. C. Floriani. P f . Zanarzi. A. R. Zanzari. Inorg. Chem. 17. 3002
(lY78): H B Chin, R. Bau, J . Am. Chem. SOC.98, 2434 (1976)
a) J. P. Collman, R. G. frnke, J N . Cawse. J I . Brauman, J. Am. Chem. SOC.
99. 2515 (1977). b) M. Darensbourg. H . Burros, C. Borman. rbid. 99. 1647
(1977).
E. L. Muetterries. T. N Rhodm. E. Band. C. F. Bricker, W. R. Prelzer. Chem.
Rev. 7Y. 91 (1979); P Chin;. 6.Longoni, V. G. Albano. Adv. Organomet.
Chem 14. 98 (1976).
G. fachinetti. J. Chem. Soc Chem. Commun. 1979. 396.
Monoclinic. P2,/c. u = 1 I 322(2). b = 11.943(3). c = 16.557(2)
p=
91 72(1)'. 2 = 4 . P ~ . , ~ &
1.68
= g/cm'. single crystal diffrdctometer CAD 4.
Mo,,, (graphite monochromator); data collection up to 2 8 = 50" (half sphere,
851 1 reflections). merging about equivalent reflections gives 3026 independent observed ones. 15 reflections suppressed because of asymmetric background. program for crystal structure determination: SHELX-76, refinement
to R=0.0758 (R,=0.0487, w=O.O58/[~r'(F)+0002 PI) for the observed reflections.
Angew. Chem. In!. Ed. Engl. 19 (19801 No. 5
A.
Fig. I . Structure of the dicdtion of (5). Bond lengths in the q'-P, ligand of the lriple-decker complex: P7 P8=2.31, P7,8 P9=2.15 A. Each metal site. M. has
50% Rh and 50% Ni (or 50% Co, in compound (41) occupancy.---Bond lengths in
complex
(4): M P,,=221-2.22
( n = 1-6).
2.29 -2.32
( n = 7 - 9);
Pn P,,=2.19-220(n=7.
8; m = 8 . 9)
[*] Prof. Dr. L. Sacconi. Dr C . Bianchini, Dr. M. Di Vaira, Dr. A. Me11
Istituto di Chimica Generale e Inorganica dell'Universita.
Laboratorio CNR.
Via J. Nardi 39, 1.50132 Firenze (Italy)
0 Verlag Chemre, GmbH. 6940 Weinherm. I980 0570-OX33/X~/05OS-405
$ 02.50/0
405
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crystals, distributions, ion, molecular, group, formation, anionic, pr2o, bridging, terminal, carbonylmetal, structure, clusters, licoo, pairs, results
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