J. Am. Chem. SOC.1992, 114, 5411-5418
[R~(Tez)7(CO)lz]2-: Hydrothermal Synthesis of a Novel Ruz+/Te2- Cluster and Its Relationship to RuTez
-OH 1 ) 10% Cp (Ph3P)pRUCI 20% N H ~ P F B
1oooc R
2) Cat RhCI, THF. 100°C
-
Song-Ping Huang and Mercouri G. Kanatzidis* R 16
15
67% (8:i) 60% (8:l) 64% (4:l)
a)R'=CH3.R2=H b) R' = PhCH,. RZ = H c) R' = H, R2 OCH,Ph
-
to the formed ring was observed in all cases. Using the 13CNMR correlations of Bartlett,g the major diastereomer was assigned as E. With allyl alcohol as the reaction partner, the initial adducts were directly equilibrated to the thermodynamically more stable (E)-a,@-unsaturated isomers. Creation of a third stereogenic center in the j3,y-unsaturated chain by using 3-buten-2-01 occurs with little selectivity (eq 5). Since the a,@-unsaturated ketones derived by simple isomerization are synthetically more useful, the lack of stereocontrol in the side chain is less consequential. Ring stereochemistry, however, continues to be high. It is interesting to note that the presence of additional free alcohol as in 17c did not interfere.
17
18
-- -
~)R'=c~H,,,R~=H b) R' H2,R2 CCHzRI c) R' H, R2-W
5% (>95 3u(F,2): 4368. A DIFABS correction was applied; p = 59.9 having : cm-I. The minimum and maximum transmissions were 0.78 and 1.27, respectively. Final R = 5.2% and R , = 5.8%.
A,
0 1992 American Chemical Society
i,
5478 J. Am. Chem. Soc., Vol. 114, No. 13, 1992 Tel6)
.8
2
Ru
6. T e
(B) Figure 1. (A) Structure of [ R U ~ ( T ~ ~ ) , ( C O ) ,with , ] ~ - the atom labeling
scheme. Some representative bond distances (A) and bond angles (deg): Ru(1)-Te(1) = 2.747 (2), Ru(2)-Te(2) = 2.690 (3), Ru(3)-Te(l) = 2.683 (3), Ru(1)-Te(7) = 2.733 (4), Ru(2)-Te(7) = 2.721 (2), Ru(3)-Te(7) = 2.734 (2), Te(1)-Te(2) = 2.763 (2), Te(7)-Te(7) = 2.717 (2), R u ( l ) C ( 2 5 ) = 1.91 (2), Ru(1)-C(26) = 1.87 (2) A; Te(1)-Ru(1)-Te(7) = 98.65 (8), Te(1)-Ru(1)-Te(3) = 90.55 (6), Te(1)-Ru(1)-Te(6) = 80.40 (6), av C - R u C = 91.7 (7), Te(l)-Te(Z)-Ru(2) = 98.82 (8), Ru(l)-Te(7)-Ru(2) = 117.74 (7), Ru(l)-Te(7)-Ru(3) = 118.08 (8)'. (B) Comparison between the [Ru6(Te2),I2- core (left) and a small-core fragment of RuTez (right).
The Te-Te and Ru-Te bond distances, with values from 2.717 to 2.763 A and from 2.673 (2) to 2.747 (2) A, respectively, are in the normal rangee7-I0 The structure of [ R u ~ ( T ~ ~ ) ~ ( C is ~peculiar ) , ~ ] ~in- that its central [ R U ~ ( T ~ core ~ ) ~is] reminiscent ~of an excised fragment of the RuTe2 pyrite-type lattice (Figure 1B). The midpoint of the central Te unit is situated a t the octahedral center with six Ru atoms as its neighbors. This is the Tez2-environment found in pyrite-l' It is tempting to conjecture that if further aggregation takes place to form the pyrite structure, this cluster core could be acting as the nucleus for crystallite growth. The close resemblance of this cluster core to the corresponding pyrite solid-state lattice imposes an unprecedented bonding feature on the central ditelluride Te2-which has not been found in any molecular species containing either S?- or Se22-ligands. The only example which can be cited for comparison is [W6(Te2)4(CO)18]2-,12 where the tellurium atoms in the central Te22- each bind to three metal atoms. However, the six tungsten atoms are in a trigonal prismatic arrangement, forming the W3Te-TeW, fragment in an eclipsed conformation. The p3-type bridging mode of the six peripheral TQ' units in [Ru~(TQ)~(CO),,]~is not known for p01ytellurides.l~ (7) Lutz, H. D.; Jung, M.; Waschenbach, G. 2.Anorg. Allg. Chem. 1987, 554, 87-91. ( 8 ) Di Vaira, M.; Peruzzini, M.; Stoppioni, P. Angew. Chem., Znt. Ed. Engl. 1987, 26, 916-917. (9) Eichhorn, B. W.; Haushalter, R. C.; Cotton, F. A.; Wilson, B. Znorg. Chem. 1988, 27,4084-4085. (IO) Mathur, P.; Thimmappa, B. H. S.; Rheingold, A. L. Znorg. Chem. 1990, 29, 4658-4665. (1 1) Wells, A. F. Structurul Inorganic Chemistry, 5th ed.; Clarendon Press: Oxford, UK, 1984; pp 758-759. (12) Roof. L. C.; Pennington, W. T.; Kolis, J. W. J . Am. Chem. Soc. 1990, 112, 8172-8174.
Communications to the Editor
With three independent ruthenium atoms of local C, symmetry, [ R ~ ~ ( T e ~ ) ~ ( c is o )expected , ~ ] ~ - to give three sets of doublet IR absorptions for the CO groups. The IR spectrum (KBr pellet) showed an overlapped absorption pattern in the CO region, a broad peak centered at 1997 an-], and three superimposed peaks at 1966, 1957, and 1948 an-',consistent with terminal CO vibrations. The W/vk spectrum of [ R U ~ ( T Q ) ~ ( C O )in~ DMF ~ ] ~ - solution features a rising band starting at -420 nm and climbing toward the ultraviolet region. Two small shoulders are identifiable a t 405 and 343 nm. The I3CN M R spectrum in DMF gave two peaks at 198 and 200 ppm, indicating that two CO groups on each Ru atom are magnetically inequivalent with respect to the central Te?-. DMF solutions of [ R U ~ ( T ~ ~ ) ~ ( C showed O ) , ~ ] three ~ - lz5Te signals, as expected, at -1606, -2978, and -3616 ppm.I4 Although we cannot assign these peaks to the corresponding three types of Te atoms in [ R U ~ ( T ~ ~ ) ~ ( C Othe ) , wide ~ ] ~ -range , of the chemical shifts observed for this compound is consistent with other metal telluride compound^.^^ In conclusion, a novel Ru2+/Te?- cluster has been made by hydrothermal synthesis which cannot, thus far, be prepared in nonaqueous solutions at ambient temperatures.I6 The structure of this compound is unique and bears remarkable resemblance to its solid-state homologue RuTe2. In this sense, [Ru6(Te2),(CO)12]2-can be regarded as an intercepted cluster on the way to RuTe2, which forms at higher temperatures. The successful synthesis of ( P ~ P ) z [ R ~ ( T e , ) 7 ( C 0 ) 1illustrates 2] the applicability of the hydrothermal technique to the preparation of novel inorganic compounds involving organometallic molecules. The reaction reported here is unexpected in two ways: (a) traditionally, water is believed to be a poor solvent for metal carbonyls at ambient temperatures and thus undesirable for chemical reactions, and (b) in general Ph4P+ salts of inorganic clusters are insoluble in water. Thus, with the altered solvent behavior of water a t superheated conditions and in the presence of alkali polychalcogenides, the disadvantage of insufficient solubility of metal carbonyls and Ph4P+ salts can be overcome. This may prove to be significant as it opens up a new dimension in synthetic organometallic research.I7 Acknowledgment. Financial support from the donors of the Petroleum Research Fund, administered by the American Chemical Society, and the National Science Foundation (Presidential Young Investigator Award, CHE-895845 1) is gratefully acknowledged. The single-crystal X-ray diffractometers used in this work were purchased with a grant from the National Science Foundation (CHE-8908088). Supplementary Material Available: Tables of crystal structure analysis, atomic coordinates of all atoms, and anisotropic and isotropic thermal parameters of all non-hydrogen atoms and Fourier transform IR spectrum for (Ph4P)2[R~6(Tez)7(Co)l*] (10 pages); listings of calculated and observed structure factors (37 pages). Ordering information is given on any current masthead page. (1 3) This bridging mode has been observed in sulfur and selenium chemistry in Cp4M4(S2)S2(M = Fe,14PC O ' ~and ~ ) [CpFe(CO)2(Se2)]BF4.1" (a) Vergamini, P. J.; Kubas, G. J. Prog. Znorg. Chem. 1976, 21, 261-282. (b) Uchtman, V. A.; Dahl, L. F. J . Am. Chem. SOC.1969, 91, 3756-3763. (c) Fritz, P. M.; Beck, W.; Nagel, U.; Polborn, K.; Herrmann, W. A.; Hecht, C.; Rohrmann, J. Z . Nuturforsch. 1988, 438, 665-670. (14) Relative to 6 = 1237 ppm for TeC1, in D20/HC1: Schumann, H.; Magerstodt, M. J. Orgunomef. Chem. 1982, 232, 147-150. (15) (a) McFarlane, H. C. E.; Mcfarlane, W. J . Chem. SOC.,Dulton Trum. 1973, 2416-2418. (b) Lesch, D. A.; Rauchfuss, T. B. Inorg. Chem. 1981,20,3583-3585. (c) Lesch, D. A.; Rauchfuss, T. B. Znorg. Chem. 1983, 22, 1854-1857. (16) Attempts to synthesize [ R U ~ ( T ~ ~ ) , ( C O )by ~ , reacting ]~Ru~(CO)~~ or (P~,P),Ru(CO)~C~, with Na2Tex (X = 2 or 4) in DMF yielded [Ru(C0),(Te4),l2-, isomorphous to [ R u ( C O ) ~ ( S ~ ~ ) , ]Draganjac, ~-: M.; Dhingra, S.; Huang, S.-P.; Kanatzidis, M. G. Inorg. Chem. 1990, 29, 590-591. (17) The reactivity of metal carbonyls with chalcogenides at ambient temperature and pressure is already an active area of research. (a) Wachter, J. Angew. Chem., Int. Ed. Engl. 1989, 28, 1613-1626. (b) Kolis, J. W. Cmrd. Chem. Rev. 1990, 105, 195-219.
