A new dichroic, nitroso-bridged complex of rhenium: Di-μ2- chloro[μ2-(η2-N,O)-N,N-dimethyl-4-nitrosoaniline] bis[tricarbonylrhenium(I)]

Article abstract of DOI:10.1002/ejic.200300928

The dimeric μ₂-amino-phenoxy complexes of rhenium [(CO) ₃Re(μ₂-∩NH₂)]₂ (1) do not react with the C-nitroso compounds R-C₆H₄NO [R = NMe ₂ (2), H (2′) in the presence of AlCl₃ by a condensation reaction to give the desired azo dye complexes [(CO) ₃Re(μ₂-O∩N=NC₆H₄R)] ₂. Instead, they react to give the novel neutral η²-N, O-bridged C-nitroso complexes [{CO)₃ReCl}₂ONC ₆H₄R] (3, 3′) by means of a substitution reaction. Both complexes yield golden gleaming crystals, and their solutions are deeply blue (3) or violet (3′) due to the broad UV/Vis absorption at λ = 617 (3) and 505 nm (3′). Single crystals of 3, 3′ show nonlinear optical properties, they are dichroic and have a red and blue (3) or violet and green (3′) side. The molecular structures of 3, 3′ have been determined by single-crystal X-ray analyses. Both compounds contain two face-joined octahedra, with two chloro and the NO ligands as bridges. The C-nitroso groups together with the NC₂ moiety of NMe₂ (3) lie almost exactly within the symmetry plane of the molecules. Both the N atoms of 3 have a trigonal-planar geometry, 3 and 3′ are the first single, neutral and dinuclear C-nitroso complexes with the rare non-assisted μ-(η²-N,O) bridge and only single atoms as additional bridges. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.

Full text of DOI:10.1002/ejic.200300928

FULL PAPER
A New Dichroic, Nitroso-Bridged Complex of Rhenium: Di-µ2-chloro[µ2-(η2-
N,O)-N,N-dimethyl-4-nitrosoaniline]bis[tricarbonylrhenium( )]
I
Roland Wilberger,[a] Christoph Krinninger,[a] Holger Piotrowski,[a] Peter Mayer,[a] and
Ingo-Peter Lorenz*[a]
Keywords: Rhenium / C,N ligand / N,O bridge / Dichroism
The dimeric µ2-amino-phenoxy complexes of rhenium
[(CO)3Re(µ2-OʝNH2)]2 (1) do not react with the C-nitroso
compounds R−C6H4NO [R = NMe2 (2), H (2Ј)] in the presence
of AlCl3 by a condensation reaction to give the desired azo
dye complexes [(CO)3Re(µ2-OʝN=NC6H4R)]2. Instead, they
react to give the novel neutral η2-N,O-bridged C-nitroso
complexes [{CO)3ReCl}2ONC6H4R] (3, 3Ј) by means of a sub-
stitution reaction. Both complexes yield golden gleaming
green (3Ј) side. The molecular structures of 3, 3Ј have been
determined by single-crystal X-ray analyses. Both com-
pounds contain two face-joined octahedra, with two chloro
and the NO ligands as bridges. The C-nitroso groups to-
gether with the NC2 moiety of NMe2 (3) lie almost exactly
within the symmetry plane of the molecules. Both the N
atoms of 3 have a trigonal-planar geometry. 3 and 3Ј are the
first single, neutral and dinuclear C-nitroso complexes with
crystals, and their solutions are deeply blue (3) or violet (3Ј) the rare non-assisted µ-(η2-N,O) bridge and only single
due to the broad UV/Vis absorption at λ = 617 (3) and 505 nm
(3Ј). Single crystals of 3, 3Ј show nonlinear optical properties,
they are dichroic and have a red and blue (3) or violet and
atoms as additional bridges.
( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2004)
Introduction
There are three types of RxNO-containing complexes
(x ϭ 0, 1). The first one (x ϭ 0) is the large and well-known
group of nitrosyl complexes.[2,3] They show the terminal lin-
ear (η1-NO, 3e-donor), bent (η1-NO, 1e-donor) or bridging
µn-NO ligand function (n ϭ 2Ϫ4). Even in the NO-contain-
ing triply bridged rhenium dimer, which is similar to 3, the
NO ligand is to be found in the terminal position.[4] Re-
cently, metastable states of [(CN)5FeNO]2Ϫ were detected
with side-on-bound NO (η2-NO) and η1-ON ligands (isoni-
trosyl).[5]
The next family are RNO· nitroxyl radicals, which nor-
mally coordinate through the oxygen atom.[6] Jaitner et al.,
however, reported on the η2-N,O coordination of the special
2,2,6,6-tetramethylpiperidine-1-oxyl (ϭ TEMPO).[7]
Recently we reported on the syntheses and structures of
several dimeric µ2-O amino-phenoxy complexes of rhenium
of the type [(CO)3Re(µ2-OʝNH2)]2 as well as on their con-
densation reactions with acetone to give the corresponding
Schiff base products [(CO)3Re(µ2-OʝNϭCMe2)]2 in almost
quantitative yields.[1] Because of the high reactivity and
good selectivity of the complexes [(CO)3Re(µ2-OʝNH2)2]
towards organic carbonyl compounds, the analogous con-
densation reaction with C-nitroso compounds should also
be possible and should yield an NϭN bond and hence the
directed synthesis of azo dyes in the coordination sphere of
a transition metal atom. The starting materials, however,
did not react, and refluxing them for more than 2 h led to
their decomposition. Attempts to catalyze the desired reac-
tion by addition of some AlCl3 for activating the nitroso
compound immediately changed the situation. After a few
minutes, the solution turned deep blue, and finally an al-
most black solid was separated, though in bad yield. Its
characterization proved it to be the novel, neutral η2-N,O-
bridged nitroso complex {(CO)3ReCl}2ONC6H4N(CH3)2
(3).
The coordination chemistry of organic RNO nitroso
compounds has also been investigated,[8] their different li-
gand functions are summarized in Scheme 1. The terminal
η2-N,O ligand function (I) dominates,[9] the η1-N,O linkage
through the nitrogen atom (II) has also been well docu-
mented,[10,11] whereas that through the oxygen atom (III)
has rarely been found.[12] The C-nitroso group may also
bridge two metal centers in an η1-N (IV),[11] an η1- and η2-
fashion [µ-(η1:η2-N,O), V][13] or as an η2-N,O moiety [µ-
(η1:η1-N,O), VI]. The latter simply as a bridging ligand is
less common;[11,14,15] most examples are known with sup-
porting second coordination by a further donor system for-
ming in addition a five- (VII)[16] or six-membered ring
(VIII).[17] Only a few examples are known for bridging two
metal atoms [µ2-(η2:η2-N,O), IX][18] or four metal atoms
[a]
Ludwig-Maximilians Universität München, Department of
Chemistry,
Butenandtstraße 5Ϫ13, 81377 München, Germany
Fax: (internat.) ϩ 49-(0)89-2180-77867
E-mail: ipl@cup.uni-muenchen.de
2488
 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
DOI: 10.1002/ejic.200300928
Eur. J. Inorg. Chem. 2004, 2488Ϫ2492

A New Dichroic, Nitroso-Bridged Complex of Rhenium
FULL PAPER
Compounds 3 and 3Ј are obtained as golden gleaming
crystals, which are stable towards air. They are soluble in
THF, toluene, ketones and CH2Cl2 and even in pentane
(3Ј). Compound 3 is not soluble in pentane. Solutions of 3
and 3Ј in CHCl3, CH2Cl2, THF or toluene are deep blue
or violet, respectively. In the UV/Vis spectrum (CHCl3) one
very broad absorption at λ ϭ 617 (3) and 505 nm (3Ј) due
to a ligand-to-metal CT band [NOϪRe()] is observed,
which is shifted to lower frequency than the corresponding
electronic transition (πϪπ* NO) of the ligands 2 (λ ϭ
419 nm) and 2Ј (λ ϭ 306 nm). Single crystals of 3 and 3Ј
show non-linear optical properties; they are dichroic and
viewed by transmitted light; they have a red and a blue (3)
or violet and green side (3Ј), respectively. The absorption
maxima of 3 are found at λ ϭ 495 and 575 nm, those of 3Ј
have not yet been measured because of technical problems.
The IR spectra of 3, 3Ј in CH2Cl2 show four ν(CO) ab-
sorptions. As the NO group coordinates to one rhenium
center with the nitrogen atom and to the other with the
oxygen atom, the electronic situation at both rhenium cen-
ters is different. Therefore, there are two different Re(CO)3
fragments, each with C3v local symmetry, and we observe
two separated patterns of ν(CO) (A1 ϩ E). Resulting from
electronic reasons, the two absorptions at higher wave-
Scheme 1. Coordination modes of C-nitroso ligands
[µ4-(η2:η2-N,O), X].[19] To the best of our knowledge type
VI is only realized, besides a special case[11] in cationic di-
mers, with two further µ2-thiolato bridges.[14]
Results and Discussion
The bad yield mentioned above and the chloro bridges
of 3 led us to repeat the reaction not catalytically, but stoi-
chiometrically. The reaction of 1, 2 and AlCl3 in the molar
ratio 1:1:2 in boiling toluene for 5Ϫ10 min resulted
in the formation of neutral di-µ2-chloro[µ2-(η2-N,O)-N,N-
˜
numbers are assigned to the {(CO)3ReϪN} fragment [ν ϭ
2041 (A1), 1946 (E) cmϪ1], whereas the two at ν˜ ϭ 2024
(A1) and 1917 (E) cmϪ1 belong to the {(CO)3ReϪO} frag-
ment as in 3. The ν(NO) of 3 absorbs significantly lower at
dimethyl-4-nitrosoaniline]bis[tricarbonylrhenium()]
(3;
ν˜ ϭ 1605 cmϪ1
.
Scheme 2), and, indeed, the yield rose to about 70%. The
same reaction was repeated with 1, 2Ј (nitrosobenzene) and
AlCl3, and the analogous nitroso complex 3Ј was obtained.
Many nitroso complexes have been synthesized by re-
duction of organic nitro compounds, which may proceed
through an intermediate nitroso compound,[8] or by a nitro-
syl migration reaction.[8]
1
The H NMR spectrum of 3 (in [D8]THF) shows two
singlets at δ ϭ 3.54 and 3.55 ppm for the N-methyl protons,
and the four double-doublets for the different pairs of o-
and m-phenyl protons (see Exp. Sect.), that of 3Ј (in
CD2Cl2) exhibits only the multiplet at δ ϭ 7.34Ϫ7.65 ppm
for the phenyl protons. In the 13C{1H} NMR spectrum of
3 (in [D8]THF) each carbon atom of the NMe2 group and
of the phenyl ring is found by separated signals between
δ ϭ 30 and 160 ppm; the signals of the CO ligands appear
at δ ϭ 190Ϫ200 ppm. The signals of the carbon atoms of
3Ј are observed at δ ϭ 129.1Ϫ131.3 ppm (phenyl) and δ ϭ
188 ppm (CO) (in CDCl2).
In the mass spectra of 3, the parent peak as well as all
signals of fragments resulting from the loss of up to six
carbonyl groups are observed.
The composition and structure of complex 3 was con-
firmed by X-ray structure analysis; single crystals were ob-
tained by diffusion of pentane into a solution of 3 in
CHCl3. The molecular structure and selected bond lengths
and angles are given in Figure 1,[20] which shows two face-
joined octahedra with two chloro and the NO ligands as
˚
bridges. The distance N(1)ϪO(1) is 1.319(8) A and clearly
longer than the NϪO distance in the free N,N-dimethyl-4-
nitrosoaniline (1.212 A[21]). The bond Re(1)ϪO(1)
˚
[2.131(6)] is shorter than the Re(2)ϪN(1) [2.208(7)],
whereas all ReϪCl bonds in the bridge are exactly the same
˚
˚
[Re(1)ϪCln ϭ 2.49 A, Re(2)ϪCln ϭ 2.49 A). The dihedral
angles Re(1)ϪO(1)ϪN(1)ϪRe(2) and O(1)ϪN(1)ϪC(1)Ϫ
C(6) are 6.54° or 12.00°, respectively; that is, the NO group
Scheme 2. Synthesis of 3, 3Ј
Eur. J. Inorg. Chem. 2004, 2488Ϫ2492
www.eurjic.org
 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2489

R. Wilberger, C. Krinninger, H. Piotrowski, P. Mayer, I.-P. Lorenz
FULL PAPER
˚
is no ReϪRe interaction [Re(1)ϪRe(2) 3.540 A (3), 3.463
˚
A (3Ј)].
Compounds 3 and 3Ј are the first simple, neutral and
dinuclear C-nitroso complexes which have the very rare
non-assisted µ-(η2-N,O) bridge (VI) and only single atoms
as additional bridges, and which have been synthesized di-
rectly by means of nitroso compounds as starting materials.
Their observed dichroism may be derived from the special
ligand function of the nitroso compound and of its place-
ment exactly in the plane of symmetry of 3 and 3Ј. In a
recent paper[22] a very similar structure of dialkylnitrosoam-
ine complexes (N-nitroso ligand) of CuII with the same µ-
(η2-N,O) coordination and with the NO group roughly par-
allel to the CuϪCu direction. Their single crystals, however,
do not exhibit the dichroic effect.
First attempts using AlX3 (X ϭ Br, I) instead of AlCl3
resulted in the formation of the corresponding bromo- and
angles [°]: Re(1)ϪC(11) 1.882(11), Re(1)ϪC(21) 1.887(10), iodo-bridged dinuclear complexes. The µ2-O-bridged pre-
˚
Figure 1. Molecular structure of 3; selected bond lengths [A] and
Re(1)ϪC(31) 1.913(11), Re(1)ϪO(1) 2.131(6), Re(1)ϪCl(2)
2.492(2), Re(1)ϪCl(1) 2.497(2), C(11)ϪO(11) 1.175(13),
cursor 1 apparently serves as a source for Re(CO)3 frag-
ments. Therefore, it might be assumed that [Re(CO)5Cl] can
be used instead of 1. First attempts with [Re(CO)5Cl] and
2 show that 3 is indeed formed.
C(21)ϪO(21) 1.161(11), C(31)ϪO(31) 1.132(11), Re(2)ϪC(22)
1.889(9), Re(2)ϪC(32) 1.891(9), Re(2)ϪC(12) 1.922(10),
Re(2)ϪN(1) 2.208(7), Re(2)ϪCl(2) 2.490(2), Re(2)ϪCl(1) 2.493(2),
C(12)ϪO(12) 1.145(10), C(22)ϪO(22) 1.170(10), C(32)ϪO(32)
1.169(10), O(1)ϪN(1) 1.319(8); C(21)ϪRe(1)ϪCl(2) 95.6(3),
Cl(2)ϪRe(1)ϪCl(1)
80.69(7),
O(1)ϪN(1)ϪC(1)
113.4(7),
Re(2)ϪCl(1)ϪRe(1) 90.36(7), Re(2)ϪCl(2)ϪRe(1) 90.53(6)
Experimental Section
General: To remove oxygen, all operations were carried out under
Ar in dry and Ar-saturated solvents.[23] [(CO)3Re(µ2-OʝNH2)]2 (1)
was prepared according to a literature procedure.[1] N,N-Dimethyl-
4-nitrosoaniline (2), nitrosobenzene (2Ј) and AlCl3 were used as
purchased. NMR spectra were recorded with a Jeol EX 400 spec-
trometer (1H: 399.78 MHz; 13C: 100.54 MHz) in [D8]THF or
CD2Cl2. Mass spectra were obtained with a Jeol MStation JMS
700. IR and UV/Vis spectra were measured with a PerkinϪElmer
Spectrum One FT-IR or PerkinϪElmer UV Lambda 16 spec-
trometer, respectively. Elemental analyses were performed with a
Heraeus Elementar Vario EL.
lies almost within the symmetry plane of the molecule,
whereas the phenyl ring is larger and turned out of this
plane. It is noteworthy that both the nitrogen atoms are
exactly trigonal planar in geometry [sum of angles for
N(1) ϭ 359°, for N(4) ϭ 360°], consistent with their sp2
nature. The analogous molecular structure was also found
for 3Ј, and is given in Figure 2.[20] In both compounds there
3: 1 (388.2 mg, 0.513 mmol), 2 (118.2 mg, 0.787 mmol) and AlCl3
(173.2 mg, 1.035 mmol) were dissolved in toluene (100 mL) and
refluxed for 10 min, whereby the solution turned deep blue. The
solvent was evaporated, the shiny blue, almost black, residue was
dissolved in CH2Cl2 and the compound purified by column chro-
matography. Yield: 258 mg (0.338 mmol, 66%), blue-red dichroic
crystals; m.p. 189Ϫ191 °C (dec.). 1H NMR (399.78 MHz,
[D8]THF): δ ϭ 3.54 [s, 3 H, N(CH3)2], 3.55 [s, 3 H, N(CH3)2], 7.24
(dd, 3J ϭ 10.16, 4J ϭ 2.64 Hz, 1 H, o-Ar-H), 7.41 (dd, 3J ϭ 10.27,
3
4
4J ϭ 2.75 Hz, 1 H, o-Ar-H), 8.02 (dd, J ϭ 10.22, J ϭ 2.64 Hz, 1
H, m-Ar-H), 8.51 (dd, 3J ϭ 10.22, 4J ϭ 2.64 Hz, 1 H, m-Ar-H)
ppm. 13C{1H} NMR (100.53 MHz, [D8]THF):
δ ϭ 30.6
(CH3NCH3), 43.1 (CH3NCH3), 118.0 (o-Ar-C), 119.2 (o-Ar-C),
128.2 (m-Ar-C), 139.4 (m-Ar-C), 160.9 (Me2NAr-Cq), 161.6
(ONAr-Cq), 191.8 (CO), 192.0 (CO), 195.3 (CO), 198.4 (CO) ppm.
IR (KBr): ν˜ ϭ 3099.1 w [ν(ArϪH)], 2938.0 w [ν(CH2)], 2857.4 w
[ν(CH2)], 2732.9 w, 2039.8 vs [ν(CO), A1], 2021.4 vs [ν(CO), A1],
1904.3 vs [ν(CO), E], 1604.4 s [ν(NO)], 1393.5 s [δ(CH3)], 1331.1 s,
1170.7 vs, 1129.8 m, 930.9 w, 879.3 w, 833.7 m [γ(Ar)], 741.3 s,
˚
Figure 2. Molecular structure of 3Ј; selected bond lengths [A] and
angles [°]: Re(1)ϪC(1) 1.906 (5), Re(1)ϪC(2) 1.976 (6),
Re(1)ϪCl(1) 2.4829 (12), Re(1)ϪN(1) 2.092 (5), Re(2)ϪC(3) 1.930 644.3 w, 565.7 w, 518.2 w, 493.5 w, 465.8 w, 398.5 w cmϪ1. IR
(8), Re(2)ϪC(4) 1.904 (6), Re(2)ϪCl(1) 2.4829 (12), Re(2)ϪO(5)
2.106 (4), O(5)ϪN(1) 1.282 (7), N(1)ϪC(5) 1.440 (8), C(1)ϪO(1)
1.145 (6), C(2)ϪO(2) 1.124 (8), C(3)ϪO(3) 1.151 (9), C(4)ϪO(4)
1.144 (7); C(1)ϪRe(1)ϪCl(1) 94.92 (14), O(5)ϪN(1)ϪC(5)
110.5 (5), Re(1)ϪCl(1)ϪRe(2) 88.41 (4).
(CH2Cl2): ν˜ ϭ 2041.4 s [ν(CO), A1], 2024.0 vs [ν(CO), A1], 1946.0
m [ν(CO), E], 1916.9 s [ν(CO), E], 1605.1 m [ν(NO)] cmϪ1. UV/
Vis (CHCl3): λ (A) ϭ 265 (0.3234), 364 (0.1048), 617 (0.9901) nm.
C14H10Cl2N2O7Re2 (761.54): calcd. C 22.08, H 1.32, N 3.68; found
2490
 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
Eur. J. Inorg. Chem. 2004, 2488Ϫ2492

A New Dichroic, Nitroso-Bridged Complex of Rhenium
FULL PAPER
Table 1. X-ray structure analysis of 3[20]
3
3Ј
Empirical formula
C14H10Cl2N2O7Re2
761.54
0.10 ϫ 0.05 ϫ 0.004
red platelet
C12H5Cl2NO7Re2
718.49
0.16 ϫ 0.24 ϫ 0.30
black block
monoclinic
C2/m
19.0607(7)
7.1842(3)
13.0451(4)
90
112.005(2)
90
Formula mass [g molϪ1
Crystal size [mm]
Crystal colour, habit
Crystal system
]
triclinic
¯
Space group
P1
˚
a [A]
6.4246(2)
9.5409(3)
16.6048(4)
83.7500(13)
83.0888(13)
70.9047(12)
952.20(5)
2
˚
b [A]
˚
c [A]
α [°]
β [°]
γ [°]
3
˚
Volume [A ]
1656.21(11)
4
2.88151(17)
14.960
Z
Density calcd. [g cmϪ3
]
2.65620(14)
13.020
696
Absorption coefficient [mmϪ1
F(000)
]
1296
Index ranges
Ϫ7 Յ h Յ 7
Ϫ11 Յ k Յ 11
Ϫ19 Յ l Յ 19
3.41Ϫ25.00
14429
3364
2737
Ϫ24 Յ h Յ 24
Ϫ9 Յ k Յ 9
Ϫ16 Յ l Յ 16
3.28Ϫ27.48
9317
2026
1864
θ range [°]
Reflections collected
Independent reflections
Observed reflections
Parameter/restrains
R1/wR2 (all data)
R1/wR2 (final)
246/0
130/0
0.0471/0.0731
0.0331/0.0694
1.112
Ϫ1.125/1.321
200(2)
Nonius Kappa CCD
area detection
SHELXS-97
SHELXL-97
0.0292/0.0560
0.0242/0.0547
1.137
Ϫ1.279/0.876
200(2)
Nonius Kappa CCD
area detection
SHELXS-97
SHELXL-97
Goodness of fit
3
˚
Min./max. ρe [e A ]
Temperature [K]
Diffractometer used
Scan type
Solution
Refinement
C 22.85, H 1.49, N 3.63. MS (DEI): m/z (%) ϭ 762.5 (56) [Mϩ],
678.4 (9) [Mϩ Ϫ 3 CO], 650.4 (62) [Mϩ Ϫ 4 CO], 622.4 (35) [Mϩ
Ϫ 5 CO], 594.4 (29) [Mϩ Ϫ 6 CO].
[1]
R. Wilberger, H. Piotrowski, P. Mayer, I..-P. Lorenz, Inorg.
Chem. Commun. 2002, 5, 897Ϫ902.
[2] [2a]
D. M. P. Mingos, D. J. Sherman, Adv. Inorg. Chem. 1989,
[2b]
3Ј: Analogous procedure as for 3, with 1 (83.9 mg, 0.111 mmol), 2Ј
(23.7 mg) and AlCl3 (29.6 mg, 0.222 mmol) in toluene (20 mL), and
stirring for 16 h, yield: 56.6 mg (0.079 mmol, 71%), violet-green
34, 293Ϫ377.
B. F. G. Johnson, B. L. Haymore, J. R.
Dilworth, Comprehensive Coordination Chemistry, Pergamon
Press, Oxford, 1987, vol. 2, p. 99Ϫ118. [2c]J. H. Enemark, R.
[2d]
1
D. Feltham, Coord. Chem. Rev. 1974, 13, 339Ϫ406.
Caulton, Coord. Chem. Rev. 1975, 14, 317Ϫ355.
K. G.
dichroic crystals; m.p. 175Ϫ181 °C (dec.). H NMR (399.78 MHz,
CD2Cl2): δ ϭ 7.34Ϫ7.65 (m, 5 H, Ar-H) ppm. 13C{1H} NMR
(100.53 MHz, CD2Cl2): δ ϭ 129.1 (Ar-C), 129.4 (Ar-C), 129.9 (Ar-
C), 131.3 (Ar-C), 188.0 (CO). IR (KBr): ν˜ ϭ 2062.8 vs [ν(CO), A1],
2029.1 vs [ν(CO), A1], 1992.7 vs [ν(CO), E], 1916.2 vs [ν(CO), E],
1579.9 m [ν(NO)], 1262.3 s, 1190.7 w, 1141.1 s, 1099.3 s, 1023.4 s,
955.1 w, 887.6 w, 802.9 s, 703.4 w, 666.0 m, 628.1 w, 640.7 w, 490.8
w, 455.5 w, 437.4 w, 408.2 w cmϪ1. IR (CH2Cl2): ν˜ ϭ 2066.8 m
[ν(CO), A1], 2023.8 vs [ν(CO), A1], 1987.8 m [ν(CO), E], 1944.6 s
[ν(CO), E] cmϪ1. UV/Vis (CHCl3): λ (A) ϭ 255 (0.670), 322 (0.275),
505 (0.623), 709 (0.267) nm. C12H5Cl2NO7Re2 (718.49): calcd. C
20.06, H 0.70, N 1.95; found C 20.18; H 0.65, N 1.91. MS (DEI):
m/z (%) ϭ 718.7 (75) [Mϩ], 634.8 (97) [Mϩ Ϫ 3 CO], 578.8 (63)
[Mϩ Ϫ 5 CO], 550.8 (100) [Mϩ Ϫ 6 CO].
[3] [3a]
A. K. Patra, R. Afshar, M. N. Olmstead, P. K. Mascharek,
Angew. Chem. 2002, 114, 2622Ϫ2625; Angew. Chem. Int. Ed.
[3b]
2002, 41, 2512Ϫ2515.
D. Gusev, A. Llamazares, G. Artus,
[3c]
H. Jacobsen, H. Berke, Organometallics 1999, 18, 75Ϫ89.
M. Schweiger, W. Beck, Z. Anorg. Allg. Chem. 1991, 595,
203Ϫ210. [3d] D. Veghini, S. E. Nefedov, H. Schmalle, H. Berke,
J. Organomet. Chem. 1996, 526, 117Ϫ134.
[4]
[5]
J. R. Norton, G. Dolcetti, Inorg. Chem. 1973, 12, 485Ϫ487.
H. Paulsen, V. Rusanov, R. Benda, C. Herta, V. Scheinemann,
C. Janiak, T. Dorn, A. I. Churmakov, H. Winkler, A. X.
Trautwein, J. Am. Chem. Soc. 2002, 124, 3007Ϫ3011.
[6] [6a]
N. Soh, T. Imato, K. Kawamura, M. Maeda, Y. Katayama,
[6b]
Chem. Commun. 2002, 2650Ϫ2651.
J. J. Watkins, A. L.
Balch, Inorg. Chem. 1975, 14, 2720Ϫ2723.
[7] [7a]
P. Jaitner, J. Veciana, C. Sporer, H. Kopacka, K. Wurst, D.
Ruiz-Molina, Organometallics 2001, 20, 568Ϫ571. [7b] P. Jaitner,
K. Jäger, A. Dorfer, K.-E. Schwarzhans, J. Organomet. Chem.
2001, 621, 173Ϫ176.
Acknowledgments
We thank Sabine Otto and Christiane Kofink for their experimen-
tal support and Dr. Gregor Jung for his UV/Vis spectroscopic
measurements.
[8]
M. Cameron, B. G. Gowenlock, G. Vasapollo, Chem. Soc. Rev.
1990, 19, 355Ϫ379.
[9] [9a]
S. Otsuka, Y. Aotani, Y. Tatsuno, T. Yoshida, Inorg. Chem.
Eur. J. Inorg. Chem. 2004, 2488Ϫ2492
www.eurjic.org
 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 2491

R. Wilberger, C. Krinninger, H. Piotrowski, P. Mayer, I.-P. Lorenz
FULL PAPER
[9b]
[13d]
1976, 15, 656Ϫ660.
L. S. Liebeskind, K. B. Sharpless, R.
Hoard, P.-R. Sharp, Inorg. Chem. 1993, 32, 612Ϫ620.
H.
D. Wilson, J. A. Ibers, J. Am. Chem. Soc. 1978, 100,
G. Ang, W. L. Kwik, K. K. Ong, J. Fluorine Chem. 1993, 60,
[9c]
7061Ϫ7063.
D. A. Muccigrosso, S. E. Jacobson, P. A. Ap-
43Ϫ48.
[14]
[15]
gar, F. Mares, J. Am. Chem. Soc. 1978, 100, 7063Ϫ7065. [9d] C.
J. Jones, J. A. McCleverty, A. S. Rothin, J. Chem. Soc., Dalton
T. Iwasa, H. Shimada, A. Takami, H. Matsuzaka, Y. Ishii, M.
Hidai, Inorg. Chem. 1999, 38, 2851Ϫ2859.
[9e]
Trans. 1985, 401Ϫ403.
M. Pizzotti, F. Porta, S. Cenini, F.
The recently reported PtϪGe complex (Et3P)2PtN(Ph)-
OGe{N(SiMe3)2}2(PtϪGe) must be viewed as a special case
obtained by cycloaddition of the corresponding germylene
complex and nitrosobenzene, and having, therefore, a very long
NϪO bond: K. E. Litz, J. W. Kampf, M. M. B. Holl, J. Am.
Chem. Soc. 1998, 120, 7484Ϫ7492.
Demartin, N. Masciocchi, J. Organomet. Chem. 1987, 330,
[9f]
265Ϫ278.
C. Crotti, C. Sishta, A. Pacheco, B. R. James,
[9g]
Inorg. Chim. Acta 1988, 141, 13Ϫ15.
M. Herberhold, A. F.
Hill, J. Organomet. Chem. 1989, 363, 371Ϫ376. [9h] S. J. Skoog,
J. P. Campbell, W. L. Gladfelter, Organometallics 1994, 13,
4137Ϫ4139. [9i] S. J. Skoog, W. L. Gladfelter, J. Am. Chem. Soc.
1997, 119, 11049Ϫ11060.
[16] [16a] E. Colacio, J. M. Dominguez-Vera, A. Escuer, R. Kivekas,
[16b]
A. Romerosa, Inorg. Chem. 1994, 33, 3914Ϫ3924.
E. Col-
[10] [10a]
acio, J. M. Dominguez-Vera, E. Escuer, M. Klinga, R. Kivekas,
A. Romerosa, J. Chem. Soc., Dalton Trans. 1995, 343Ϫ348. [16c]
E. Colacio, J. M. Dominguez-Vera, A. Escuer, R. Kivekas, M.
R. G. Little, R. J. Doedens, Inorg. Chem. 1973, 12,
[10b]
537Ϫ540.
W. L. Bowden, W. F. Little, T. J. Meyer, J. Am.
[10c]
Chem. Soc. 1974, 96, 5605Ϫ5609.
W. L. Bowden, W. F.
[10d]
Klinga, J.-M. Moreno, A. Romerosa, J. Chem. Soc., Dalton
Little, T. J. Meyer, J. Am. Chem. Soc. 1976, 98, 444Ϫ448.
[16d]
Trans. 1997, 1685Ϫ1689.
K. K.-H. Lee, W.-T. Wong, J.
D. Mansuy, M. Dreme, J.-C. Chottard, J. Guilhem, J. Or-
[10e]
Chem. Soc., Dalton Trans. 1997, 2987Ϫ2995.
ganomet. Chem. 1978, 161, 207Ϫ220.
tioni, J.-C. Chottard, C. Riche, A. Chiaroni, J. Am. Chem. Soc.
D. Mansuy, P. Bat-
[17] [17a]
E. Colacio, J. M. Dominguez-Vera, A. Romerosa, R. Ki-
[10f]
vekas, M. Klinga, A. Escuer, Inorg. Chim. Acta 1995, 234,
1983, 105, 455Ϫ463.
C. J. Jones, J. A. McCleverty, A. S.
[17b]
[10g]
61Ϫ65.
E. Colacio, C. Lopez-Magana, V. McKee, A. Ro-
Rothin, J. Chem. Soc., Dalton Trans. 1985, 401Ϫ403.
C.
merosa, J. Chem. Soc., Dalton Trans. 1999, 2923Ϫ2926.
M. J. Scott, S. J. Lippard, Organometallics 1998, 17, 466Ϫ474.
G. Gervasio, R. Rossetti, P. L. Stanghellini, Chem. Commun.
1997, 387Ϫ388.
Crotti, C. Sishta, A. Pacheco, B. R. James, Inorg. Chim. Acta
[18]
[19]
1988, 141, 13Ϫ15. [10h] J. Chang, M. D. Seidler, R. G. Bergman,
[10i]
J. Am. Chem. Soc. 1989, 111, 3258Ϫ3271.
McGettigan, G. L. Geoffro, A. L. Rheingold, S. J. Geib, Or-
R. S. Pilato, C.
[20]
[10j]
CCDC-229256 (3) and -229255 (3Ј) contain the supplementary
crystallographic data for this paper. These data can be obtained
free of charge at www.ccdc.cam.ac.uk/conts/retrieving.html [or
from the Cambridge Crystallographic Data Centre, 12 Union
Road, Cambridge CB2 1EZ, UK; Fax: (internat.) ϩ 44-1223-
336-033; E-mail: deposit@ccdc.cam.ac.uk].
C. Romming, H. J. Talberg, Acta Chem. Scand. 1973, 27,
2246Ϫ2248.
ganometallics 1990, 9, 312Ϫ317.
W. H. Chin, K.-K.
Cheung, C.-M. Che, J. Chem. Soc., Chem. Commun. 1995,
[10k]
441Ϫ442.
J.-L. Liang, J.-S. Huang, Z.-Y. Zhon, K.-K.
Cheung, C.-M. Che, Chem. Eur. J. 2001, 7, 2306Ϫ2317.
[11]
D. L. Packett, W. C. Trogler, A. L. Rheingold, Inorg. Chem.
1987, 26, 4308Ϫ4309.
[21]
[12] [12a] G. Matsubayashi, K. Nakatsu, Inorg. Chim. Acta 1982, 64,
[12b]
[22]
[23]
L163ϪL164.
S. Hu, D. M. Thompson, P. Ikekwere, R. J.
A. Schmidpeter, H. Nöth, Inorg. Chim. Acta 1998, 269, 7Ϫ12.
Trocknen im Labor, brochure from the series ‘‘Reagenzien’’,
Merck, Darmstadt.
Barton, K. E. Johnson, B. E. Robertson, Inorg. Chem. 1989,
28, 4552Ϫ4554.
[13] [13a]
M. Calligaris, T. Yoshida, S. Otsuka, Inorg. Chim. Acta
Received December 9, 2003
Early View Article
Published Online April 7, 2004
[13b]
1974, 11, L15ϪL16.
Barnes, J. Am. Chem. Soc. 1990, 112, 2024Ϫ2026.
P. R. Sharp, D. W. Hoard, C. L.
[13c]
D. W.
2492
 2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
Eur. J. Inorg. Chem. 2004, 2488Ϫ2492