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Directed Synthesis of Trinuclear Hydrocarbon-Bridged Complexes such as [(OC)5ReCH2CH2Os(CO)4CH2CH2Re(CO)5].

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[l] Compare a) T. G. Spiro (Ed.): Mefal Ions in Biology. Vul. 4 (Iron Sulfur
Proteins) and Vul. 7 (Molybdenum Enzymes), Wiley, New York 1982 and
1987; b) M . J. Nelson, P. A. Lindahl, W. H. Orme-Johnson in G . L. Bchhorn, L. G . Marzilli (Ed.): Adv. Inorg. Biochemistry, Vut. 4 , Elsevier, Amsterdam 1982, p. 1.
[2] Regarding terminology cf. K. Mislow, J. Siegel, J Am. Chem. Suc. 106
(1984) 3319.
[3] X-ray structure analysis of 2: P2,/c, a = 1272.8(5), b = 1534.1(23), c =
1633.6(16)pm, p = 104.76(8)"; V = 3085(2) x lo6 pm3; Z = 4. T = 200 K,
Mo,. irradiation; w-scan; 3.0 .c w < 15" min-I, 4" 2 8 < 52". 5328 independent reflections, for 3287 of which F > 6m(F). SHELXTL-PLUS, direct
methods, R = 0.078, R, = 0.065. Further details of the crystal structure
investigation are available on request from the Fachinformationszentrum
Karlsruhe. Gesellschaft fur wissenschaftlich-technische Information mhH,
D-7514 Eggenstein-Leopoldshafen 2 (FRG), on quoting the depository
number CSD-54803, the names of the authors, and the journal citation. A
comparison between experimental and simulated powder diagrams (LAZYPulverix) for aa-Z(RR)/act-Z(S.S)-2 shows that the isolated product, consisting of blocks and intertwined prisms, must contain an additional isomer
of 2.
141 Regarding the dimerization of homochiral fragments or racemic heterochiral fragments cf. F. A. L. Anet, S . S . Miura, J. Siegel, K. Mislow, J. Am.
Chem. SOC.105 (1983) 1419.
[S] R . S assignment according to R. S. Cahn, C. K. Ingold, V. Prelog, Angew.
Chem. 78 (1966) 413; Angew. Chem. hi[.Ed. Engf. 5 (1966) 385; based on
IUPAC nomenclature the Rand S isomers would be referred to as A and A
isomers. respectively; cf. Deutsches ZentralausschuD fur Chemie (Ed.): Internaliunale R q e l n fur die chemische Nomenklatur und Terminolugie, Band
1 , Gruppe I, Verlag Chemie, Weinheim 1976, p. 100. As indicated in this
source, the IUPAC nomenclature for describing octahedral complexes with
multidentate ligands remains unsatisfactory.
[6] Compare a ) C. H. Winter, A. M. Arif, J. A. Gladysz, Organometallics 8
(1989) 219; b) G . Wilkinson, R. D. Gillard, J. A. McCleverty (Ed.): Cumprehrnsive Coordination Chemistry, Pergamon, Oxford 1987; c) J. M. B.
Harrowfield, S. B. Wild in [6h], Vul. 1, p. 179; D. A. House in [6b], Vul. 2,
p. 23, G. B. Kaufmann, Cuurd. Chem. Rev. 12 (1974) 105.
[7] D. Sellmann. H. E. Jonk, H. R. Pfeil, G. Huttner, J. von Seyerl, .l
OrRanumet. C'hem. 191 (1980) 171.
Scheme 1. HC
=
unsaturated hydrocarbon.
case of the dialkyl(tetracarbony1)osmium compounds cis[R,OS(CO),],[~] the hydrocarbon bridges in 1-4 are cis to
each other.
1
co
2
co
3
4
Directed Synthesis of
Trinuclear Hydrocarbon-Bridged Complexes such as
[(OC),ReCH,CH,Os(CO),CH,CH,Re(CO),] **
By Wolfgang Beck,* Burkhard Niemer, and Barbara Wagner
Dedicated to Professor Alfred Schmidpeter on the occasion
of his 60th birthday
The nucleophilic addition of carbonylmetalates to coordinated, unsaturated hydrocarbons in cationic complexes is a
method that lends itself to the directed synthesis of a variety
of hydrocarbon-bridged complexes.l'] Previously we have
utilized only monoanions for this purpose, for example
[Re(CO),]", leading to heterobimetallic complexes. We are
now able to report that the dianion [Os(CO),]'@ ['* 3l permits
the efficient synthesis of trinuclear hydrocarbon-bridged
complexes (Scheme 1).
The complexes 1-4 were obtained in good yield by treatment of [OS(CO),]~~
with the cations 5-8 (in THF). The
Re, compound 9 was identified as a byproduct of 1.As in the
[*] Prof. Dr. W. Beck, DipLChem. B. Niemer, Dip].-Chem. B. Wagner I + ]
Institut fur Anorganische Chemie der Universitit
Meiserstrasse 1. D-8000 Munchen 2 (FRG)
['I X-ray structural analysis
I**] Hydrocarbon-Bridged Complexes, Part 14. This work was supported by
the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen
Industne. We wish to thank Professor Dr. F: R. Kreissl, Technische Universitat Munchen, for mass spectra, and Professor Dr. G. Hutfner,Universitit
Heidelberg, and Dr. K . Karaghiusoff, Universitat Munchen, for helpful
discussions. Part 13: J. Breimair, M. Steimann, B. Wagner, W. Beck, Chem.
Ber., in press.
Angen,. Chem. Int. Ed. Engl. 28 (1989) Nu. 12
0 VCH
Compounds 1-4 were characterized on the basis of
spectroscopic data (Table 1); in addition, 2-4 were the
subject of X-ray structural analysis.r91The mass spectrum of
1 reveals signals not only for the molecular ion but also
for the cleavage products [(OC),OsC,HaRe(CO),]@ and
[(OC),Re(C,H,)]@ and fragments corresponding to succes-
Table 1. IR[a] together with 'H- and "C-NMR spectroscopic data for 1-4.
1 (in pentane):
= 2119w, 21 low, 2033%2009vs, 1983m
2 (in C,H,): V = 2113w. 2067vw, 2040s,sh. 2030s, 2013vs, 2006vs, 1930vs.hr
3 (in pentane): V = 2138w, 2070m, 2053vs. 2044m, 2022m,sh, 2015~s.2005vw,
194Os, 1926s
4 (in CH,CI,): i = 2121w, 2040s, 2015m, 1978vs,br, 1907s,br, 1872s.br
1 (CD2C12,270 MHz): A A B B spectrum, 6 = 2.08 - 1.91. 14 lines
2 [D],toluene, 90MHz, -72°C): 6 = 5.20 (t, 4-H), 3.76 (dd. 3.5-H), 2.95
(t,l-H), 2.47 (dd,2,6-H); (+26 "C): b = 3.73 (br); (+52"C): b = 3.80(s)
3 (C,D,): 6 = 5.08 (br.1 H). 5.05 (br, 1 H), 4.71 (br, 2 H). 3.86 (br, 1 H), 3.79
(br, 1 H). 2.92 (br, 1 H), 2.86 (hr,t H)
4 (CD2C1,): 6 = 6.23 (dd,4,5-H), 4.50 (m, 3,6-H), 4.26 (t. 2,7-H), 3.68 (t,l-H)
I(CD,CI,, 67.8 MHz): 6 = 187.26(ReCOe,), 181.90(ReCO,,), 172.44(OsCO),
12.04, 4.45
3 (C,D,): 6 = 174.65 (OsCO,,), 168.54 (OsCO.,), 88.93. 88.75, 69.27, 69.19,
68.95, 68.75, 49.07, 48.63. MnCO signal not detectable
4 (CDKI,): 6 = 176.71 (OsCO.,). 169.57 (OsCO,,), 100.87 (C-4.5) 97.94 (C3,6), 82.77 (C-2,7), 18.09 (C-l), MoCO signal not detectable
[a] v(C0) bands in cm-'.
Verlagsgese//schaf~mbH, 0.6940 Weinheim. 1989
OS70-0833/89/1212-1705$02.50/0
1705
sive loss of CO. The 'H-NMR spectrum of 1 shows the
typical pattern for an AA'BB' system at 6 = 2.00. 1 is isolobal[*]with n-heptane, and can be regarded as a 1,7-dirhena4-osma-n-heptane.
The OsMn, complex 2 displays the same dynamic behavior in solution as the bimetallic complex l(OC)3Mn(p-qs:q'C6H6)Re(CO),].r'01Thus, the 'H-NMR spectrum of 2 at
25 "C in [D,]toluene shows only a broad signal at 6 = 3.73.
Below - 45 "C fluctuation is suppressed, so signals for the
frozen cyclohexadienyl bridges appear. A benzene-bridged
structure [((0C),Mne(p-q4:~*-C6H6)},0s2@(C0),]
with
18 valence electrons on each of the metal atoms seems plausible as a transition state for the fluctuation. Both the 'Hand 13C-NMR spectra of 3 contain double sets of signals,
suggesting the formation of isomers. The molecular structure of crystalline 3 (Fig. 1) reveals exo placement of the
04
Os(CO), group on the two five-membered rings; the sulfur
atoms are "trans" to each other. The two stereogenic carbon
atoms bound to osmium have the same configuration. Bond
lengths and angles in the [Mn(CO),(thiophene)] unit are
comparable to those in the adduct of cyanide with
[(CO),Mn(q5-thiophene)]@,in which the C,H,S ring acts as
an allylsulfide donor.[61The 0s-C o-bonds of 3 have lengths
(223(3) and 218(3) pm) similar to those in, for example,
[(OC),Os(CH,C,F,),] (216(2) and 220(2) pm).["l Addition
of organic nucleophiles to metal-coordinated thiophene has
been studied as a model reaction for the catalytic hydrodesulfurization of petroleum.['21
Based on our experiences, [Re(C0),le, [RU(CO),CP]~,
and [OS(CO),]'~ are especially well-suited to the directed
synthesis of hydrocarbon-bridged compounds. They are
sufficiently nucleophilic for the purpose, and they also
form stable metal-carbon o-bonds. It is tempting to consider
the preparation of higher polynuclear complexes through
the use of highly reduced metal carbonyls['31 such as
0 VCU
Experimental Procedure
All experiments were conducted under argon with carefully dried solvents.
4: To a beige suspension of 90 mg (0.26 mmol) of Na,Os(CO), in 5 mL of THF
(- 70 "C) were added 185 mg (0.52 mmol) of [(C,H,)Mo(CO),][BF,]. The solvent was removed in vacuo at - 25°C from the red suspension after 1 h. The
residue was then washed once with 10 mL of pentane, and 4 was extracted with
10 mL of CH,CI,. Removal of solvent and drying (4 h) in high vacuum provided 4 as a red powder that gave dark red needles upon recrystallization from
toluene (0°C). Yield 190 mg (87%), decomposition above 110°C.
The complexes 1 (colorless needles, yield 65%), 2, and 3 (orange-yellow crystals, yield 40%) were prepared similarly, with slight modifications in the
workup.
Received: July 3 , 1989
Supplemented: August 28, 1989 [Z 34201
German version: Angew. Chem. 100 (1989) 1699
03
Fig. I.Molecular structure of crystalline 3 ; ellipsoids at the 20% probability
level. Space group Pi, a = 789.2(4), b = 1158.1(7), c = 1461(1)pm; a =
78.93(6), p = 75.82(5), y = 87.81(4)"; V = 1.270(1) nm'; Z = 2. h (Mo,,) =
71.069 pm; crystal size = 0.2 x 0.2 x 0.4 mm', ~(Mo,) = 6.14 mm-' (corrected for absorption). w-Scan, d o = 2.0", 8 s 61 5 30 min-', 4 2 2 8 2 50"; 4123
reflections collected, 3928 independent, 2450 observed [ I > 2u(I)]. Number of
refined parameters, 159; heavy atoms 0 s . Mn, and S anisotropy. R = 0.081.
R, = 0.079, w = [u2(Fo)
+ gF;]-', g = 0.0006. Maximum residual electron
e pm--). Hdensity 2.66, minimum residual electron density - 1.55 x
atoms placed in calculated positions.-Selected bond lengths b m ] and angles
["I: O K 1 4 223(3), OS-CIS 218(3), S IC14 183(3), S K I 1 176(3), S2-Cl8
181(2), S2-Cl5 165(4), Mnl-SI 231(1), Mn2-S2 229(1); Os-CI4-Sl 119(1), OsC14-CI3 li5(2), Os-C18-S2 120(1), Os-CI8-Cl7 117(2), C18-0s-Cl4 87(1),
C4-Os-C3 90(2).-Further details of the crystal structure investigation are
available on request from the Fachinformationszentrum Karlsruhe, Gesellschaft fur wissenschaftlich-technische Information mbH, D-7514 EggensteinLeopoldshafen 2 (FRG) by quoting the depository number CSD-54043, the
names of the authors, and the journal citation.
1706
[Re(C0)J3@. Such polynuclear heterometallic complexes
are of interest as potential precursors to heterogeneous catalysts."4'
Verlagsgesellschafl mbH. 0-6940 Weinheim, 1989
[I] W. Beck, Polyhedron 7 (1988) 2255; W. Beck, B. Niemer, J. Breimair, J.
Heidrich, J. Organomel. Chem. 372 (1989) 79.
[2] R. D. George, S. A. R. Knox, F. G. A. Stone, 1 Chem. Soc. Dalton Trans.
1973,972; J. P. Collman, D. W Murphy, E. B. Fleischer, D. Swift, Inorg.
Chem. f 3 (1 974) 1.
[3] F. L'Eplattenier, C. Pelichet, Helv. Chim. Acta 53 (1970) 1091; W. J. Carter,
J. W Kelland, S. J. Okrasinski, K. E. Warner, 3. R. Norton, Inorg. Chem.
21 (1982) 3955.
[4] K. Raab, U. Nagel, W. Beck, 2. Naturforsch. B 38 (1983) 1466; W. Beck,
K. Raab, Inorg. Synth., in press.
[S] G. Winkhaus, L. Pratt, G. Wilkinson, J. Chem. Soc. 1961, 3807.
161 D. A. Lesch, J. W. Richardson, Jr., R. A. Jacobson, R. J. Angelici, J. Am.
Chem. SOC.106 (1984) 2901.
[7] J. D. Munro, P. L. Pauson, J. Chem. SOC.1961, 3475; R. B. King, M. B.
Bisnette, Inorg. Chem. 3 (1964) 785; A. Salzer, H. Werner, Z . Anorg. Allg.
Chem. 418 (1975) 88.
[8] R. Hoffmann, Angew. Chem. 94 (1982) 725; Angew. Chem. Int. Ed. Engl.
21 (1982) 711.
191 The structural analyses of 2 and 4 will be described separately; M. Steimann, B. Wagner, B. Niemer, W. Beck, unpublished results.
[lo] B. Niemer, M. Steimann, W. Beck, Chem. Ber. f 2 i (1988) 1767.
[ l l ] G. G. Aleksandrov, G. P. Zol'nikova, I. I. Kritskaya, Yu. T. Struchkov,
Sov. 1 Coord. Chem. 6 (1980) 305.
I121 R. J. Angelici, Acc. Chem. Res. 21 (1988) 387; G. N. Glavee, L. M. Daniels,
R. J. Angelici, Organometallics 8 (1989) 1856.
[13] G. F. P. Warnock, L. C. Moodie, J. E. Ellis, J. Am. Chem. Soc. 111 (1989)
2131, and references cited therein.
[14] I.H. Sinfelt: Bimetallic Catalysts: Discoveries, Concepts and Applications,
Wiley, New York 1983; P. Braunstein, R. Devenish, P. Gallezot, B. T.
Heaton, C . J. Humphreys, J. Kervennal, S. Mulley, M. Ries. Angew. Chem.
100 (1988) 972; Angew. Chem. Int. Ed. Engl. 27 (1988) 927.
Stereoselective Synthesis of y-Aminocarboxylates**
By Manfred 7: Reetz,* and Dirk Rohrig
Owing to their well documented and potential biological
and pharmacological activity the stereoselective synthesis of
non-proteinogenic amino acids has assumed great importance."' We report here on a method whereby a-amino acids
1 can be converted into y-amino acid esters of type 2 containing a new stereocenter. Accordingly, the stereoselective formation of the two possible diastereomers 2 can be controlled,
[*I Prof. Dr. M. T. Reetz, Dipl.-Chem. D. Rohrig
Fachbereich Chemie der Universitat
Hans-Meenvein-Strasse, D-3550 Marburg (FRG)
[**I This work was supported by the Deutsche Forschungsgemeinschaft
(SFB260) and the Fonds der Chemischen Industrie.
0570-0833/89/12i2-i706 $02.50/0
Angew. Chem. Int. Ed. Engl. 28 (1989) No. 12
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