A cascade cycloaddition strategy leading to the total synthesis of (-)-FR182877

Article abstract of DOI:10.1002/1521-3773(20020517)41:10<1737::AID-ANIE1737>3.0.CO;2-4

A tandem transannular [4+2] cycloaddition strategy is presented for the synthesis of the class of natural products containing FR182877 (1) and hexacyclinic acid (2). As part of this program, a tandem transannular [4+2] cycloaddition reaction has been empl

Full text of DOI:10.1002/1521-3773(20020517)41:10<1737::AID-ANIE1737>3.0.CO;2-4

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[15] M. J. Hostetler, W. L. Manner, R. G. Nuzzo, G. S. Girolami, J. Phys.
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11553.
the H1B atoms and the Cu surface. The corresponding distance
between the H1B atoms of cyclopropane and the surface is
3.0 ä. It thus appears that the dispersion forces for cyclo-
propane are not quite strong enough to push the molecule as
deeplyinto the surface, which results in a lesser degree of
charge transfer into the molecule than occurs for cyclohexane.
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Experimental Section
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V. Barone, M. Cossi, R. Cammi, B. Mennucci, C. Pomelli, C. Adamo,
S. Clifford, J. Ochterski, G. A. Petersson, P. Y. Ayala, Q. Cui, K.
Morokuma, D. K. Malick, A. D. Rabuck, K. Raghavachari, J. B.
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Liashenko, P. Piskorz, I. Komaromi, R. Gomperts, R. L. Martin, D. J.
Fox, T. Keith, M. A. Al-Laham, C. Y. Peng, A. Nanayakkara, C.
Gonzalez, M. Challacombe, P. M. W. Gill, B. G. Johnson, W. Chen,
M. W. Wong, J. L. Andres, M. Head-Gordon, E. S. Replogle, J. A.
Pople, Gaussian, Inc., Pittsburgh, PA, 1998.
The UHV chamber used in these experiments was operated at a base
[19, 20]
pressure of <3.0 Â 10À10 Torr and has been described previously.
The
RAIRS data were collected with a Digilab FTS 60A spectrometer with a
liquid nitrogen cooled wide-band MCT detector in conjunction with
external reflection optics, maximized for single grazing angle reflection.
The crystal temperature was monitored by a chromel-alumel thermocouple
lodged in a hole on the side of the crystal. The crystal could be cooled and
heated within the temperature range of 100 950 K. The crystal was
‡
cleaned bysputtering with 1 keV Ar ions for 30 min at 850 K and then
annealed for 15 min at 850 K. The adsorbates were introduced into the
chamber byusing an effusive molecular beam doser located approximately
5 cm from the crystal. Cyclopropane (>99%) was obtained from Aldrich
and used as received. Cyclohexane (>99%) was obtained from EM
Science and degassed byfreeze-pump-thaw cycles before introduction into
the chamber. The pressure during dosing varied between 1 Â 10À9 and 5 Â
10À7 Torr. Exposures, reported in Langmuirs (1 Â 10À6 Torr), are not
corrected for the ion gauge sensitivity.
[23] B. C. Laskowski, P. S. Bagus, Surf. Sci. 1984, 138, 1142.
[24] P. S. Bagus, K. Weiss, A. Schertel, C. Wˆll, W. Braun, C. Hellwig, C.
Jung, Chem. Phys. Lett. 1996, 248, 129 135.
Ab initio calculations: The calculations for cyclopropane and cyclohexane
[21]
adsorbed on Cu(111) closelyfollow an approach described previously.
Briefly, high-quality ab initio Hartree Fock calculations were carried out
for a (7,3)-cluster exhibiting C3v symmetry modeling a Cu(111) surface with
a Cu lattice constant of 2.54 ä using a commercial software package
(Gaussian 98[22]). Correlation effects were included at the MP2 level. For
the Cu atoms a 28-electron pseudopotential (see reference [21] and [23] for
a detailed discussion) together with an extensive basis set for the remaining
electrons was used together with a 6-311 ‡‡ basis set for the C and the H
atoms. This basis set has been demonstrated to be sufficientlylarge to
account for the details of the alkane electronic structure seen in X-ray
absorption spectroscopy[24] and to the corresponding adsorption-induced
changes in those data.[21] Previous work has shown that this theoretical
approach provides a veryreasonable potential for the ccylopropane/
Cu(111) interaction, giving good agreement with experimental quantities
such as the binding energyand the curvature of the surface molecule
potential.[21] All results reported here were obtained for the electronic
ground state of the Cu(7,3)-cluster, which is a triplet state.
Pentaphosphaferrocene as a Linking Unit for
the Formation of One- and Two-Dimensional
Polymers**
Junfeng Bai, Alexander V. Virovets, and
Manfred Scheer*
Dedicated to Professor Joachim Str‰hle
on occasion of his 65th birthday
Common approaches in the field of self-organization of
discrete supramolecular[1] aggregates, networks, and coordi-
nation polymers[2] make use of N-donor containing ligands
and N-heterocycles to connect different metal centers togeth-
er. In contrast, however, our goal in this field has been the use
of Pn-ligand complexes as linking moieties between metal
cations to form well-oriented assemblies as well as one-
dimensional (1D) and two-dimensional (2D) polymers.
The coordination chemistryof P n-ligand complexes[3] to-
wards cationic metal centers (excluding cationic organo-
metallic complex moieties[4]) has so far been limited to the use
of cyclo-P3-ligand complexes, such as [(triphos)M(h3-P3)]
(M ˆ Co, Rh, or Ir; triphos ˆ 1,1,1-tris(diphenylphosphanyl-
methyl)ethane), which usually form metal-bridged dimers.[5]
Received: August 22, 2001
Revised: December 27, 2001 [Z17775]
[1] G. Ertl, H. J. Freund, Phys. Today 1999, 52, 32 38.
[2] W. M. H. Sachtler, Ber. Bunsen-Ges. 1995, 99, 1295 1305.
[3] G. A. Somorjai, Introduction to Surface Chemistryand Catalsyis
Wiley, New York, 1994.
,
[4] G. Blyholder, J. Phys. Chem. 1964, 68, 2772.
[5] P. S. Bagus, K. Hermann, W. M¸ller, C. J. Nelin, Phys. Rev. Lett. 1986,
57, 1496.
[6] A. Fohlisch, M. Nyberg, J. Hasselstrom, O. Karis, L. G. M. Pettersson,
A. Nilsson, Phys. Rev. Lett. 2000, 85, 3309 3312.
[7] K. Hermann, M. Witko, Surf. Sci. 1995, 337, 205.
[8] L. Pettersson, H. Agren, Y. Luo, L. Triguero, Surf. Sci. 1998, 408, 1
20.
[9] L. Triguero, L. G. M. Petterson, B. Minaev, H. Agren, J. Chem. Phys.
1998, 108, 1193 1205.
[10] L. Triguero, A. Fohlisch, P. V‰terlein, J. Hasselstrom, M. Weinelt,
L. G. M. Pettersson, Y. Luo, H. Agren, A. Nilsson, J. Am. Chem. Soc.
2000, 122, 12310 12316.
[11] J. Chatt, L. A. Duncanson, J. Chem. Soc. 1953, 2939.
[12] M. J. S. Dewar, Bull. Soc. Chim. Fr. 1951, 18, C79.
[13] J. E. Demuth, H. Ibach, S. Lehwald, Phys. Rev. Lett. 1978, 40, 1044.
[14] R. Raval, M. A. Chesters, Surf. Sci. 1989, 219, L505 L514.
[*] Prof. Dr. M. Scheer, Dr. J. Bai, Dr. A. V. Virovets
Institut f¸r Anorganische Chemie der Universit‰t Karlsruhe
Engesserstrasse, Geb. 30.45
76128 Karlsruhe (Germany)
Fax : (‡49)721-608-7021
E-mail: mascheer@chemie.uni-karlsruhe.de
[**] This work was supported bythe Deutsche Forschungsgemeinschaft
and the Fonds der Chemischen Industrie.
Angew. Chem. Int. Ed. 2002, 41, No. 10
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1737

COMMUNICATIONS
In the reactions of the Co complex with CuBr, a
multidecker Co complex containing a (CuBr)6
middle deck was obtained,[6] whereas for
the Ir complex, the cationic product
‡
[{(triphos)IrP3}3Cu5Br4] was formed.[7] However,
recentlywe were able to show that [{CpMo-
(CO)2}2(m,h2-P2)] (Cp ˆ C5H5) can be used as a
building block to connect CuI and AgI centers to
form 1D polymers such as the complexes 1 and
2.[8] Further, we have tried to incorporate com-
pound 3 (Cp* ˆ C5Me5)[9] into these investiga-
tions. In the past few years, the reaction behavior
of 3 has been intensivelyexamined bythe group
of O. J. Scherer.[3f]
Figure 1. View of the 1D chain structure of complex 4 (H atoms are omitted for clarity).
Selected bond lengths [ä] and angles [8]: P1-P5 2.109(2), P1-P2 2.119(1), P2-P3 2.124(2),
P3-P4 2.123(2), P4-P5 2.121(1), Cu-P1 2.286(1), Cu-P5 2.272(1), Cu-Cl 2.356(1), Cu-Cl'
2.342(1); P5-Cu-P1' 111.02(5), P5-P1-Cu 126.19(5), Cu'-Cl-Cu 83.94(4), Cl-Cu-Cl' 95.43(4).
[Ag2{Cp2Mo2(CO)4(m,h2:h1:h1-P2)}3(m,h1:h1-NO3)]1 [NO3]n
1
À
ingly, the P P bond between the coordinating atoms P1 and
[Cu(m-Br){Cp2Mo2(CO)4(m,h2:h1:h1-P2)}]1
[Cp*Fe(h5-P5)]
2
À
P
P5 is slightlyshorter (2.109(2) ä) than the remaining P
bonds of the cyclo-P5 ring (2.119(1) 2.124(1) ä), whereas the
latter are nearlyconsistent with those of the uncoordinated
molecule 3 (2.117(4) ä), as determined byelectron diffrac-
3
tion.[16] However, compared to the P P bonds in the related
À
Besides its capacityto form cationic triple-decker com-
plexes[10] or undergo P5-transfer reactions,[11] there are reac-
tions known in which the cyclo-P5 ring remains more or less
intact, or is cleaved with formation of a P5 chain, or P4/P1, P3/
P2, or P2 fragments.[3f, 10 12] In the case where the cyclo-P5 ring
remains intact, h5:h1, h5:h2, and h5:h2:h2:h1 coordination modes
to organometallic fragments have been found,[13] which are
accompanied bya significant lengthening of the P P bonds.
Herein we report the first use of the cyclo-P5 ligand complex 3
to form novel 1D and 2D polymers by the hitherto unknown
1,2-ligation and 1,3,4-ligation, respectively, to different Cu
complex [CpxFe(m,h5-P5)] (7; Cpx ˆ h5-C5Me4Et; 2.088(3)
2.108(3) ä), determined bysingle-crsytal X-raystructure
[17]
À
analysis, the P P bonds of 4 are slightlylengthened.
Nevertheless, this coordination behavior of the cyclo-P5
moietyin 4 is in contrast to the previouslyobserved
À
lengthening of the P P bonds on the coordination of organo-
metallic fragments to the cyclo-P5 ring.[13] For example, the
additional side-on coordination of an organometallic frag-
ment at the cyclo-P5 ring in [Cp*Fe(m,h5:h2-P5)Cp*Ir(CO)]
À
I
À
leads to a lengthening of the corresponding P P bond to
2.359(2) ä.[13b] Furthermore, h1 coordination of the [{Cp*Ir-
(CO)}2] unit in [Cp*Fe(m,h5:h1-P5)(Cp*IrCO)2][13a] leads to
ions.
Complexes 4 6 were obtained bythe reaction of 3 with
CuX (X ˆ Cl, Br, I) in solvent mixtures of CH3CN and CH2Cl2
À
P P bond lengths about the coordinating P atom of 2.166(3)
and 2.170(3) ä as well as a significant bending of the cyclo-P5
ring, which results in a P4/P1 arrangement. In contrast,
therefore, the cyclo-P5 units in the polymers 4 6 are still
essentiallyplanar.
In the crystal lattice of both 5 and 6 the distorted
[CuCl{Cp*Fe(h5:h1:h1-P5)}]1
[CuBr{Cp*Fe(h5:h1:h1:h1-P5)}]1
[CuI{Cp*Fe(h5:h1:h1:h1-P5)}]1
4
[18]
5
I
6
tetrahedrallycoordinated Cu atoms are surrounded byone
halogen atom and three P atoms each coming from three
different [Cp*Fe(h5-P5)] fragments (Figure 2). Thus, a new
h5:h1:h1:h1 coordination mode is obtained which result in a
novel 1,3,4 substitution pattern at the cyclo-P5 ring. In contrast
to the structure of 4, and as a result of the additional third
coordination of the CuIX moietyat the cyclo-P5 rings in 5 and
6, novel 2D coordination polymers are formed where the
layers are separated by the Cp*Fe moieties (Figure 3). The
at ambient temperature. The yellow-brown crystals of the
products are stable under nitrogen and in common solvents
are insoluble without decomposition.[14] All the products have
[15]
been characterized byX-raydiffraction analysis.
In Figure 1 the linear 1D chain structure of 4 is depicted, it
consists of planar six-membered Cu2P4 and four-membered
Cu2Cl2 rings, alternatelyarranged in an orthogonal manner.
The planar cyclo-P5 rings are coplanar with the six-membered
≈
structure of 6 (space group P421c) is similar to that of 5 (space
I
≈
group P421m) except that the latter possesses no symmetry
Cu2P4 units, and the coordination geometryaround the Cu
plane within the crystallographic c axis, which leads to a
mirror plane within the Cp*FeP5 moieties of 6. Within the
layers of 5 and 6 (Figure 4) there is an alternating arrayof six-
membered Cu2P4 rings and novel Cu4P12 rings. The Cu2P4 rings
are in a boatlike conformation, unlike the previouslyreported
center is tetrahedral. Furthermore, the 1,2 coordination of the
cyclo-P5 ring to two different metal centers has not been
observed before. The structure of 4 is reminiscent of the 1D
polymeric structure of the Mo2P2-containing complex 2, with
the difference that, aside of the different Pn ligand used, the
Cu2Cl2 moieties in 4 are bent along the Cl Cl axis, and the
CuI atoms are nonsymmetrically bound to the P (2.272(1) and
2.286(1) ä) and Cl atoms (2.356(1) and 2.342(1) ä). Interest-
À
planar Cu2P4 rings in the 1D polymer of 2. The P P distances
[18]
within the nearlyplanar
cyclo-P5 moieties of 5 (2.099(2)
2.108(2) ä) and 6 (2.114(3) 2.120(3) ä), are comparable to
1738
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1433-7851/02/4110-1738 $ 20.00+.50/0
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the distances within 4 and are slightlyshorter than those of the
uncoordinated 3 (2.117(4) ä)[16] but slightlyelongated in
comparison to the related complex
7
(2.088(3)
2.108(3) ä).[17] Thus, as alreadydiscussed for 4, the coordina-
tion of CuI halides in 5 and 6 does not influence the
À
corresponding P P bond lengths.
The tendencyfor the reaction of 3 with CuCl on the one
hand and CuBr/CuI on the other to yield products with
disparate structures is surprising and difficult to explain.
Whereas within the CuCl product 4 the linear chains are
separated from each other by p stacking between Cp* and
cyclo-P5 moieties of different chains, 5 and 6 form 2D
networks through additional metal coordination to the
cyclo-P5 rings rather than p stacking.
In summary, the results have shown that in addition to
[{CpMo(CO)2}2(m,h2-P2)], the complex [Cp*Fe(h5-P5)] (3) can
also be successfullyused as a linking unit for coordination
polymers, which opens perspectives to generate novel well-
defined assemblies and networks. In contrast to previously
reported reactivitystudies of 3 with organometallic com-
Figure 2. View of the coordination geometryaround a Cu atom within the
polymeric structure of complex 5 (H atoms are omitted for clarity).
Selected bond lengths [ä] and angles [8]: P1-P5 2.106(2), P1-P2 2.108(2),
P2-P3 2.104(2), P3-P4 2.101(2), P4-P5 2.099(2), Cu-P1 2.320(1), Cu-P3
2.278(1), Cu-P4 2.281(1), Cu-Br 2.343(1); P1-Cu-P3 103.01(5), P1-Cu-P4
103.98(5), P3-Cu-P4 104.48(5), P1-Cu-Br 101.24(4), P3-Cu-Br 122.27(5),
P4-Cu-Br 119.03(4).
À
plexes, where the P P bond lengths of the
products have been significantlylength-
ened and the cyclo-P5 ring is partially
À
distorted, the P P bonds of the planar
cyclo-P5 ring in the new coordination
polymers 4 6 do not differ significantly
to those of 3.
Experimental Section
4
6:
A
solution of CuX (0.15 mmol; X ˆ Cl
(28 mg)) in CH3CN
(15 mg), Br (21 mg),
I
(3 mL) and CH2Cl2 (2 mL) was added to a solution
of 3 (52 mg, 0.15 mmol) in CH2Cl2 (5 mL) at room
temperature. This mixture was allowed to stand
for two days, and yellow-brown crystals of 4
(33 mg, 0.067 mmol, 49%), 5 (65 mg, 0.13 mmol,
89%), and 6 (78 mg, 0.14 mmol, 93%), respec-
tively, were formed. The products were collected
byfiltration and washed with 2 mL each of CH 2Cl2
and CH3CN, and then dried under vacuum; 4 ¥
0.5CH2Cl2: elemental analysis (%) calcd for
Figure 3. View of the zigzag 2D layer structure of complex 6 along the b axis (H atoms are
omitted for clarity). Selected bond lengths [ä] and angles [8]: P1-P2 2.114(3), P1-P1' 2.116(4), P2-
P3 2.120(3), P3-P2' 2.120(3), Cu-P1 2.296(2), Cu-P1' 2.296(2), Cu-P3 2.332(3), Cu-I 2.549(2); P1-
Cu-P1' 106.59(12), P1-Cu-P3 105.15(9), P1'-Cu-P3' 105.14(9), P1-Cu-I 119.28(7).
C10.5H16Cl2CuFeP5 (487.37):
C 25.88, H 3.28;
found: C 26.03, H 3.22; 5: elemental analysis
(%) calcd for C10H15BrCuFeP5 (489.39): C 24.54,
H 3.09; found C 24.64 H, 3.15; 6: elemental
analysis (%) calcd for C10H15ICuFeP5 (536.40): C
22.39, H 2.82; found C 22.30, H 2.96.
Received: December 18, 2001 [Z18411]
[1] Recent review articles: a) P. J. Stang, B.
Olenyuk, Acc. Chem. Res. 1997, 30, 502
518; b) D. Braga, F. Grepioni, G. R. Desiraju,
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Figure 4. View of layer of the 2D structure of complex 6 orthogonal to the a,b plane (H atoms are
omitted for clarity).
Angew. Chem. Int. Ed. 2002, 41, No. 10
¹ WILEY-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002
1433-7851/02/4110-1739 $ 20.00+.50/0
1739

COMMUNICATIONS
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0.1312. CCDC 175139 175141 contain the supplementarycrystallo-
graphic data for this paper. These data can be obtained free of charge
via www.ccdc.cam.ac.uk/conts/retrieving.html (or from the Cambridge
Crystallographic Data Center, 12, Union Road, Cambridge CB21EZ,
UK; fax: (‡44)1223-336-033; or deposit@ccdc.cam.ac.uk).
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[18] Mean deviation from planarity: 0.0098(6) ä (4), 0.0293(9) ä (5),
0.0350 (20) ä (6).
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Structure and Synthesis of the Natural
Heptachloro-1'-methyl-1,2'-bipyrrole (Q1)
Jun Wu, Walter Vetter,* Gordon W. Gribble,*
John S. Schneekloth, Jr., David H. Blank, and
Helmar Gˆrls
A number of anthropogenic organohalogen compounds
such as polychlorinated biphenyls (PCBs), polychlorinated
dibenzo-p-dioxins (PCDDs), and chlorinated pesticides
(DDT, toxaphene, lindane, and others) are recognized as
persistent, bioaccumulative, and toxic chemicals.[1] The ma-
jorityof these substance classes are ubiquitouslydistributed in
the environment, and long-term exposure is one of the major
threats to humans and wildlife from these substances.[2] The
scientific interest in anthropogenic halogenated compounds is
reflected in the fate of these contaminants and related
compounds in the environment, which was reported on in
more than 1000 publications in the past 40 years.
More than 3600 naturallyoccurring organohalogens have
been identified to date.[3] The total amount of these com-
pounds is not known, but is probablyhigher than currently
known.[4] It was thought that these natural products are
neither persistent nor lipophilic, and thus do not accumulate
in the lipids of higher organisms. This hypothesis is currently
under reconsideration, as recent work has resulted in the
detection of a series of unknown halogenated compounds that
[11] B. Rink, O. J. Scherer, G. Wolmersh‰user, Chem. Ber. 1995, 128, 71
74.
[12] a) O. J. Scherer, T. Mohr, G. Wolmersh‰user, J. Organomet. Chem.
1997, 529, 379 385; b) C. Hoffmann, O. J. Scherer, G. Wolmersh‰user,
J. Organomet. Chem. 1998, 559, 219 222; c) B. Koch, O. J. Scherer, G.
Wolmersh‰user, Z. Anorg. Allg. Chem. 2000, 626, 1797 1802.
[13] a) M. Detzel , T. Mohr, O. J. Scherer, G. Wolmersh‰user, Angew.
Chem. 1994, 106, 1142 1144; Angew. Chem. Int. Ed. Engl. 1994, 33,
1110 1112; b) M. Detzel, G. Friedrich, O. J. Scherer, G. Wolmer-
sh‰user, Angew. Chem. 1995, 107, 1454 1456; Angew. Chem. Int. Ed.
Engl. 1995, 34, 1321 1223; for NMR spectroscopic evidence for
h5:h2:h1 coordination of 3 see: c) G. Friedrich, Dissertation, Universi-
t‰t Kaiserslautern, 1995; M. Detzel, Dissertation, Universit‰t Kaiser-
slautern, 1995; d) O. J. Scherer, S. Weigel, G. Wolmersh‰user, Chem.
Eur. J. 1998, 4, 1910 1916.
[14] Because to their insolubility, no NMR spectroscopic investiga-
tion could be carried out. Solid-state NMR investigations are in
progress.
[15] Crystal structure analyses of 4 6 were performed on STOE IPDS
diffractometers with MoKa radiation (l ˆ 0.71073 ä) for 5 and AgKa
radiation (l ˆ 0.56087 ä) for 4 and 6. The structures were solved by
direct methods with the program SHELXS-97,[19a] and full-matrix
least-squares refinement on F 2 in SHELXL-97[19b] was performed with
anisotropic displacements for non-hydrogen atoms. Hydrogen atoms
were located in idealized positions and refined isotropicallyaccording
to the riding model. 4 ¥ 0.5 CH2Cl2: C10.5H16Cl2CuFeP5, Mr ˆ 487.37,
crystal dimensions 0.20 Â 0.14 Â 0.04 mm3, monoclinic, space group
C2/c (No. 15), a ˆ 20.184(4), b ˆ 16.885(3), c ˆ 13.860(3) ä, b ˆ
[*] Priv.-Doz. Dr. W. Vetter, Dr. J. Wu
Lehrbereich Lebensmittelchemie
Friedrich-Schiller-Universit‰t Jena
Dornburger Strasse 25, 07743 Jena (Germany)
Fax : (‡49)3641-949-652
129.33(3)8,
Tˆ 203(2) K,
Z ˆ 8,
Vˆ 3653.7(13) ä3,
1calcd
ˆ
ˆ
1.772 MgmÀ3
,
m ˆ 1.382 mmÀ1
, 3831 independent reflexes (Rint
0.0365, 2qmax ˆ 428), 3128 observed with Fo ˆ 4s (Fo), 190 parameters,
E-mail: walter.vetter@uni-jena.de
R1 ˆ 0.0370, wR2 ˆ 0.0974. 5: C10H15BrCuFeP5, M ˆ 489.37, crystal
dimensions 0.20 Â 0.20 Â 0.01 mm3, tetragonal, space group P421c
Prof. Dr. G. W. Gribble, J. S. Schneekloth, Jr., Dr. D. H. Blank
Department of Chemistry, 6128 Burke Laboratory
Dartmouth College
≈
(No. 114), a ˆ b ˆ 12.147(2), c ˆ 21.859(4) ä, Tˆ 200(1) K, Z ˆ 8,
Vˆ 3225.2(9) ä3, 1calcd ˆ 2.016 MgmÀ3, m ˆ 5.170 mmÀ1, 3152 inde-
pendent reflexes (Rint ˆ 0.0777, 2qmax ˆ 528), 2681 observed with Fo ˆ
4s (Fo), 168 parameters, R1 ˆ 0.0345, wR2 ˆ 0.0809. 6: C10H15CuFeIP5,
Mr ˆ 536.36, crystal dimensions 0.10  0.10  0.10 mm3, tetragonal,
Hanover, NH 03755 (USA)
Fax : (‡1)603-646-3946
E-mail: gordon.w.gribble@dartmouth.edu
≈
space group P421m (No. 113); a ˆ b ˆ 12.372(2), c ˆ 11.241(2) ä, Tˆ
Priv.-Doz. Dr. H. Gˆrls
203(1) K, Z ˆ 4, Vˆ 1720.6(5) ä3, 1calcd ˆ 2.071 MgmÀ3
,
m ˆ
Institut f¸r Anorganische und Analytische Chemie
Friedrich-Schiller-Universit‰t Jena
Lessingstrasse 8, 07743 Jena (Germany)
2.258 mmÀ1, 8297 independent reflexes (Rint ˆ 0.1663, 2qmax ˆ 408),
1475 observed with Fo ˆ 4s (Fo); 94 parameters, R1 ˆ 0.0496, wR2 ˆ
1740
¹ WILEY-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002
1433-7851/02/4110-1740 $ 20.00+.50/0
Angew. Chem. Int. Ed. 2002, 41, No. 10