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Multicomponent Self-Assembly Preferential Generation of a Rectangular [2 3]G Grid by Mixed-Ligand Recognition.

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15a, R' = H, R2= H
OR1
ORZ
154 R' = H, R2= tBu
F n o c - I l e I- S e r - G l y I- I l e - S e r - G l y - I l e - G l y - [ ~ A ) ~ ~ ~
1% R' = tBu, RZ= H
15d, R1 = tBu, R2= tBu
-
Keywords: compound libraries glycopepglycosylations solid-phase syntides
thesis
-
S . Lavielle, N. C. Ling, R. C. Guillemin, Carbohydr.
Res. 1981, 89, 221-228; H. Paulsen, G. Merz, U.
Weichert, Angew. Chem. 1988, 100, 1425- 1427;
Angew. Chem. Int. Ed. Engl. 1988, 27, 1365-1367;
OH
OH
H. Kunz, B. Dombo, ibid. 1988,100,732-734 bzw.
1988, 27, 711-713; M. Meldal, K. J. Jensen, J
Chem. SOC.Chem. Commun. 1990,483-485;
S . Peters, T. Bielfdd, M. Meldal, K. Bock, H.
Paulsen, L Chem. Soc. Perkin Trans f 1992, 11631171.
HO
I
M. Meldal, Curr. Opin. Struct. Biol. 1994, 4, 710H
O
P
16b
738.
HO
M. Meldal In Neoglyconjugate: Preperation and ApHO
HO 'OH
plications (Eds.: Y.C. Lee, R. T. Lee), Academic
Press, San Diego, 1994, pp. 145-198.
HO .OH
HO ,OH
H. Paulsen, S . Peters, T Bielfeld in Glycoproteins:
Chemical Synthesis of Glycopeptides (Eds.: J. Montreuil, J. F. G. Vliegenthart, H. Schachter), Elsevier,
Amsterdam, 1995, pp. 87-121
H. Paulsen, A. Schleyer, N. Mathieux, M. Meldal,
Bz-Ile -Se r-Gly-Ile-d r-Gly-Ik -Gly-OMe
Bz-IleSe r-Gly-Ile-~r-Gly-Ile-Gly-OMe
K. Bock, J. Chem. SOC.Perkin Trans. 1 1997, 281I
HO
293.
0. Seitz, H. K u n z , J Org. Chem. 1997,62, 813-826.
L. Yan, L. C. M. Taylor, R. Goodnow, Jr., D.
Kahne, J Am. Chem. SOC.1994,116,6953-6954.
M. Meldal in Methods of Enzymology: Solid-Phase
Peptide Synthesis (Ed.: G. Fields), Academic Press,
Scheme 3. Synthesis of a small library of glycopeptides by two consecutive, direct glycosylations of a mixture
San Diego, 1997, in press.
of solid phase-bound peptides. a) Piperidine/DMF; b) BzOH, TBTU, NEM; c) Bz,Gal-TCA, TMS-OTf; d)
R. C. Sheppard, Science Tools 1986,33,9-16.
TFA/H,O; e) Ac,Fuc-TCA, TMS-OTP; f ) NaOMe/MeOH.
M. Meldal, Tetrahedron Lett. 1992, 33, 3077-3080.
M. Meldal, K. Bock, GlycoconjugafeJ 1994, I f , 5963.
Table 3 . Masses (m/z)of purified compounds determined by MALDI-TOF-MS.
[13] M. Renil, M. Meldal, Tetrahedron Lett. 1996, 37, 6185-6188.
[14] H. Rink, Tetrahedron Lett. 1987, 28, 3787-3790.
[IS] C. P. Holmes, D. Jones, J. Org. Chem. 1995, 60, 2318-2319.
m/r [M Na']
Compound
m/z [M Na']
Compound
[16] R. R. Schmidt, W. Kinzy, Adv Carbhydr. Chem. Biochem. 1994, 21 -123; S .
4a
670.8
14
686.9
Rio, J.-M. Beau, J.-C. Jacquinet, Carbohydr. Res. 1991, 219, 71-90.
4b
689.2
16a
1169.7
1171 T. M. Windholz, B. R. Jonston, Tetrahedron Lett. 1%7, 2555-2558.
7
1152.4
16b
1154.2
[18] H. Paulsen, B. Helpap, Carbohydr. Res. 1991, 2f6, 289-313.
1191 E. Meinjohans, M. Meldal, H. Paulsen, K. Bock, J Chem. SOC.Perkin Trans
8
1095.1
16c
1154.2
1 1995,405-415.
11
1002.5
16d
1136.7
[201 G. Barany, R. B. Merrifield, 1 Am. Chem. SOC.1977,99, 7363-7365.
13
671.8
[21] The 'H NMR spectrum indicated the equal formation of Bz-IS(Fuc)GIS(Ga1)GIG-OMe and Bz-IS(Gal)GIS(Fuc)GIG-OMe (eluted from HPLC as a
single peak). The combination of the corresponding COSY and NOESY spectra showed the NOE cross-peaks of the FucH1/GalH'and the Ser-Hb at 6 = 4.0,
nose gave the corresponding glycopeptides in high yields after
3.9, 3.8, and 3.7 indicate the linkage of the sugar units to the Ser-hydroxy
cleavage. The protected 8-galactopyranosyl peptide was deprogroups.
I
+
+
tected in solution to yield the unprotected D-galactopyranosyl
peptide. With perbenzoylated or peracetylated 2-azido-2-deoxycm-galactopyranosyl trichloroacetimidate, the corresponding
a-glycosylated products were formed in good yields.
On peptides attached through a HMBA-linker, glycosylation
reactions with peracetylated trichloroacetimidates of L-fucopyranose, D-mannOpyranOSe, and D-galactopyranose afforded the
corresponding unprotected glycopeptides upon cleavage with
NaOMe. tert-Butyl ether protecting groups were sufficiently
stable when short glycosylation times could be employed.
Longer reaction times resulted in some cleavage of tBu, particularly from tert-butyl esters (data not presented). Use of temporary tBu-protection of some serine hydroxy groups led to quantitative glycosylation of a model library consisting of four
different octapeptide templates with two different glycosyl acceptor sites. The peracetylated trichloroacetimidates of L-fucose
and D-galactopyranose were used in two sequential glycosylation steps to produce the four different unprotected glycopeptides obtained after cleavage from the resin.
Received: March 5 , 1997 [Z10204IE]
German version: Angew. Chem. 1997, 109,2061-2067
1978
0 WILEY-VCH Verlag GmbH, D-69451 Weinheim, 1997
Multicomponent Self-Assembly: Preferential
Generation of a Rectangular [2 x 3]G Grid by
Mixed-Ligand Recognition**
Paul N. W. Baxter, Jean-Marie Lehn,*
Boris 0. Kneisel, and Dieter Fenske
Self-assembly processes offer a particularly attractive method
for preparing nanosized supramolecular devices in that the required structural complexity of such entities can be accessed in
['I
[**I
Prof. Dr. J.-M. Lehn, Dr. P. N. W. Baxter
Laboratoire de Chimie Supramoleculaire, Institut Le Be1
Universite Louis Pasteur, CNRS URA 422
4, rue Blaise Pascal, F-67000 Strasbourg (France)
Fax number: Int. code + 3 884-110
e-mail: lehn@chimie.u-strasbg.fr
B. 0. Kneisel, Prof. Dr. D. Fenske
Institut fur Anorganische Chemie der Universitat Karlsruhe (Germany)
We thank Patrick Maltese for the ROESY and '"Ag NMR measurements.
0570-0833/97/3618-1978$17.50+ .50/0
Angew. Chem. Int. Ed. Engl. 1997.36. NO. 18
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a single step from a mixture of suitably tailored molecular components." -41 The generation of multimetallic arrays by metal
ion directed self-assembly is especially interesting in this respect,
as the presence of metal ions may endow the resulting inorganic
architecture with novel redox, optical, magnetic, and other
properties. Recent examples from this class of compounds include h e l i ~ a t e s ,51~cages,16]
~.
r~taxanes,'~]
and grids.[*,91 The formation of a [3 x 3]G silver grid[*]demonstrated the feasibility of
self-assembling two-dimensional square [n x n] arrays of metal
ions (n = 3), which may be considered as ion dots. Following
the generation of [n x n]G symmetrical grids, their rectangular
[rn x n]G counterparts are especially attractive synthetic targets,
as they constitute a potentially much larger class of compounds,
and may therefore present a greater diversity of properties and
possible applications.
We herein report the formation of the first example of the
rectangular grid 1, which spontaneously and preferentially selfassembles upon combination of tri- and ditopic ligands 2 and 3
with AgCF,SO, in a 2:3:6 stoichiometric ratio in nitromethane
(Scheme 1); minor amounts of the corresponding square grids
2
cal and magnetic environment, as indicated by five aromatic
signals in a 2:2:2:2:2 ratio, which correspond to the H3, H4,
and H5 protons of the outer pyridine rings and the H 4 and H5'
protons of the inner pyridazine rings. Ligand 3 appears as two
sets of signals in a 2: 1 ratio, each set comprising four bands due
to the H3, H4, and H5 protons of the pyridine rings and the
equivalent H4/H5' protons on the pyridazine ring. This pattern
is consistent with two outer and one inner ligands 3 in 1. The
CH, protons give three peaks in a 6:6:3 ratio, which is also
indicative of 2 in a single and 3 in two different environments in
a ratio of 2(2):2(3): l(3). In addition, the pyridazine H4'/H5'
singlet of the inner 3 ligand is shifted upfield relative to that of
the outer two 3 ligands. This shielding effect is what would be
expected for protons on a ring situated within structure 1. The
'09Ag NMR spectrum shows two signals in a 2: 1 ratio corresponding to four outer and two inner Ag' ions, respectively.
An X-ray crystal structural determination" '1 of the reaction
product confirmed the structure as 1-(CF3S03),(Figure 1). The
3
1
Scheme 1. Self-assembly of the rectangular (2 x 3]G grid complex 1; the spheres
represent Ag' ions
are also found (see Scheme 2). The structural formulation of the
product as 1.(CF,SO,), is based on elemental analysis, X-ray
crystallography, and 'H, 13C, and '09Ag NMR spectroscopy.
The product incorporates a two dimensional [2 x 3]G rectangular array of six silver@)ions, and therefore represents the first
member of a homologous series of [rn x n]G rectangular grids
(m#n).
The 'H NMR spectrum["] of the solution obtained by dissolving 2, 3, and AgCF,SO, in a 2:3:6 ratio in CD3N0, gave
the first indication of structure 1. The spectrum is clean and free
from overlapping bands. Ligand 2 is situated in a single chemiAngtw. Chem. Inr Ed Engl. 1997,36,No. 18
Figure 1. Two views of the crystal structure of the self-assembled[2 x 3]G rectangular grid [Ag6(2),(3)J6' (1): ball-and-stick (top) and space-filling representations
(bottom).
crystals consist of [Ag6(2),(3),l6 + ions, uncoordinated triflate
anions, as well as nitromethane and water molecules. The six
silver ions in 1are arranged in the form of a 2 x 3 rhombohedralIy distorted rectangular matrix. The dihedral angle described by
the rhombus (between the mean planes of ligands 2 and 3) is
about 66", and the average Ag-Ag separation is 3.75 A. The
vertex silver ions Agl, Ag3, Ag4, and Ag6 lie almost in a plane
with distances Agl-Ag4 3.79, Agl-Ag3 7.63, Ag3-Ag6 3.72,
and Ag4-Ag6 7.45 A, and inner angles AgCAgl-Ag3 65 and
0 WILEY-VCH Verlag GmbH, D-69451 Weinheim, 1997
0570-0833/97/3618-1979$17.50+.50/0
1979
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Agl-Ag4-Ag6 115". The six silver ions define a slightly Ushaped surface along the longer axis of 1, in which Ag2 and Ag5
lie 0.19 and 0.25 A, respectively, above the mean plane through
Agl, Ag3, Ag4, and Ag6. All the silver ions possess a distorted
tetrahedral coordination polyhedron with an average dihedral
angle of 71 O between the N-Ag-N planes of ligands 2 and 1. The
four vertex silver ions are each coordinated to two pyridine and
two pyridazine nitrogen atoms (mean Ag-N 2.30 A), and the
two central Ag ions to one pyridine and three pyridazine nitrogen atoms (mean Ag-N 2.35 A). This situation is reflected in
the '09Ag NMR spectrum of 1, in which the signal due to the
vertex Ag ions is shifted downfield by A6 = 59 ppm from that of
the central Ag ions. This is in agreement with the chemical shifts
observed for a f3 x 3]G nonasilver grid.'']
The five ligands in 1 are divided into two sets comprising two
units of 2 and three units of 3 lying above and below the mean
plane through the six Ag' ions. Each ligand forms a slightly
twisted blade conformation due, in part, to the summed effects
of intra-ligand steric repulsions (maximum dihedral inter-ring
twist angle 12"). The average distance between the ligand mean
planes is 3.36 8, and therefore slightly larger than the
van der Waals contact distance of about 3.4 A. The overall dimensions of 1 are 15.19 x 11.07 A, which places the grid just
within the nanostructural domain. The shortest distance between the grid cations within the crystal lattice is 3.4 A.
The spectroscopic and crystallographic evidence unambiguously supports the identity of the product from the reaction of
2, 3, and AgCF,SO, in a 1 :1.5:3 ratio as that of hexanuclear
rectangular [2 x 3]G grid 1 both in solution and in the solid state.
Complex 1 forms spontaneously by the self-assembly of eleven
particles, that is, five ligand components of two types and six
silver ions. On the basis of the instructions contained in the
ligands and the coordination algorithm of the metal-ion connectors, the mixed-component process by which a rectangular grid
is generated represents a step further in complexity in terms of
information content with respect to the formation of symmetric
[nx n]G grids, which involves only a single ligand species.
The preferential formation of a mixed-ligand entity is especially noteworthy, as the system made up of 2,3, and Ag' in a
1:1.5:3 ratio has the potential to give three different product
distributions (Scheme 2): 1 ) statistical distribution, 2) homo
ligand recognition in which ligands only recognize individuals of
their own identity to yield [2 x 2]G and [3 x 3]G symmetrical
grids, and 3) hetero ligand assembly, that is, selective association between ligands of different type resulting in the generation
of 1. Upon completion of the reaction, 1 .(CF,SO,), coexists in
CD,NO, with a mixture of 8 % [Ag4(3)4](CF,S0,)4 and 2 %
[Ag,,(Z),](CF,SO,),, as indicated by the 'H NMR spectrum of
12x2
12x3
f
i-12x6
Y
2--h
36%(8%)
Nitromethane (3 mL) was added to 2 (0.026 g, 7.64 x
mol), 3 (0.030 g,
1.14 x
mol), and the mixture submol), and AgCF,SO, (0.059 g, 2.30 x
jected to brief ultrasonication. All suspended solids rapidly dissolved to give a
yellow solution, which was stirred at room temperature for 36 h and then filtered.
The solvent was removed under reduced pressure. The remaining solid was suspended in benzene (8 mL), homogenized by brief ultrasonication, isolated by filtration
under vacuum, washed with excess benzene, and dried in the air and then under
mmHg and 70°C. The yellow powder obtained (yield 0.114 g,
vacuum at 2 x
99%) could be either pure l.(CF,SO,), or a mixture with the square grids; it was
recrystallized quantitatively from nitromethane/benzene [lO,11].
l.(CF,SO,),: 'HNMR (CD,NO,, 500 MHz, 25°C). 6 = 9.146 (d, J(5',4) =
9.4 Hz, H S (Z)), 9.081 (d, 4 4 ' 3 ) = 9.4 Hz, H 4 (Z)), 8.774 (s, H4' (outer 3)), 8.575
(s, H 4 (inner 3)), 8.264 (d, J(3,4) = 8.2 Hz, H3 (Z)), 8.171 (d. J(3,4) = 8.0 Hz, H3
(outer3)),7.977(t,J(3,4,5) =7.9Hz,H4(2)),7.914(t,J(3,4,5) =7.9Hz,H4(outer
3)), 7.816 (d, J(3,4) = 8.0 Hz. H3 (inner 3)), 7.691 (t. J(3,4,5) =7.9 Hz, H4 (inner
3)),7.438(d,J(5,4) =7.7Hz,HS(2)),7.353(d,J(5,4)-7.7Hz,H5(outer3)),7.211
(d, J(5,4) =7.7 Hz, H5 (inner 3)), 2.373 (s, CH, (inner3)), 2.258 (s, CH, (Z)), 2.244
(s, CH, (outer 3)). All of the protons assigned represent a symmetric pair of protons
on each ligand. I3C NMR (CD,NO,, 75 MHz, 25'C): 6 = 161.20, 161.01, 160.83,
158.11, 156.38, 155.28, 153.70. 147.26, 147.05, 145.82, 142.91, 142.20, 142.16,
132.37, 132.31, 131.23, 131.08, 129.98, 129.90, 129.50, 123.81, 123.30, 123.17;
28.40, 27.53, 27.38 (CH,); 124.59, 120.34 (CF,SO;); '"Ag NMR (CD,NO,,
18.625 MHz, 25°C): 6 = 572.63 (Ag, vertex), 513.12 (Ag, central); elemental analC 37.52, H 2.48, N 11.17; found: C 37.35,
ysis calcd for C,,H,,Ag,F,,N,,O,,S,:
H 2.61, N 11.32.
Received: March 10, 1997 [Z10219IE]
German version: Angew. Chem. 1997, 109, 2067-2070
-
16%(2%)
12
487490%)
Scheme2. Possible self-assembly pathways for 2, 3, and Ag' in a 2:3:6 ratio:
a) homo and b) hetero ligand selection; statistically expected values and actual
yields (in parentheses) are given for both cases.
1980
Experimental Section
Keyw&~$ Faordination modes
N Iigands : self-assembly silver
+4
9
the solution. This ratio appears to be independent of concentration. Helicate mixtures exhibit either partial or exclusive homo
ligand recognition.['4. 151 The preference for hetero over homo
ligand recognition in the case of 1 may derive in part from an
avoidance to form the [3 x 3]G complex, which possesses the
least stable metal-Pgand coordination site, that is, the central
Ag(pyridazine), unit. Solvation and thermodynamic considerations also play a role. An understanding of the factors which
result in a preference for hetero over homo ligand assembly will
be of great importance for the future design of disymmetric
metal-ion arrays.
The successful preparation of 1 opens the way to metal ion
mediated self-assembly of nonsymmetric [mx n]G ion grids
( m2 2, n 2 3, and m # n for m and n binding sites). Because such
disymmetric grids must, by definition, be mixed-ligand species,
they present a larger variety of possible combinations of the
ligands involved than their symmetric [n x n]G congeners.
Therefore, they could find a greater number of applications, for
example as components within a futuristic information storage
and processing nanotechnology. To uncover and exploit the
novel physicochemical properties that such systems may possess, detailed investigations into electronic, magnetic, surface
chemical, and interfacial behavior will be necessary. Furthermore, methods for the fabrication of polynuclear architectures
of higher dimensionality and techniques for their incorporation
into larger organized superstructures may also be envisioned.
0 WILEY-VCH Verlag GmbH, D-69451 Weinheim, 1997
-
multinuclear complexes
*
[I] J. S . Lindsey. N e n J. Ckem 1991, 15, 153.
[2] D. S . Lawrence, T. Jiang, M. Levett, Chem. Rev. 1995, 95,2229.
[3] J.-M. Lehn, Supramolecular Chemistry: Concepts and Perspectives, VCH,
Weinheim, 1995, chap. 9.
141 D. Philp, J. F. Stoddart, Angen. Chem. 1996,108,1242; Angew. Chem. Inr. Ed.
Engl. 19%, 35, 1154.
[5] E. C. Constable, Terrahedron 1992, 48, 10013; K. T. Potts. M.Keshavarz-K,
F. S . Tham, H. D. Abrufia, C. Arana, Inorg. Ckem. 1993, 32, 4436, and references therein.
[6l a) P. N. W. Baxter, J.-M. Lehn, A. DeCian, J. Fischer, Angew. Chem. 1993,
lOS, 92; Angen. Chem. I n t . Ed. Engl. 1993,32, 69; b) M. Fujita, S. Nagao, K.
Ogura, J. Am. Chem. Soc. 1995, 11 7, 1649.
[7] H. Sleiman, P. N. W Baxter, J.-M. Lehn, K. Rissanen, J. Chem. SOC.Chem.
Commun. 1995, 715.
0570-0833/97/3618-1980$17.50+ .50/0
Angew. Chem. Inr. Ed. Engl. 1997,36, No. 18
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[S] P. N. W. Baxter, J.-h4. Lehn, J. Fischer, M.-T. Youinou, Angew. Chem. 1994,
ducting binary- and ternary-phase materials.[’’ Homoleptic
106, 2432; Angen. Chem. Inr. Ed. Engl. 1994,33, 2284.
[M(ER),] (M = metal, E = chalcogen) complexes decompose
191 M:T. Youinou, N. K?hmouni, J. Fischer, J. A. Osborn, Angen. Chem. 1992,
with elimination of ER, and formation of the corresponding
104, 771 ; Angiw. Chem. Int. Ed. Engl. 1992,31, 133.
binary solid materials “ME”.[3a1Studies in this area have includ[lo] ‘H NMR spectral assignments were made on the basis of ‘H- ‘H ROESY and
COSY measurements. The spectra of the crude and recrystallized materials
ed chalcogenolate complexes of Group 12 elements,[31and rewere identical, indicating that the different grid species present equilibrate. In
cent efforts have focused on related lanthanide,l4] early transiaddition. mixing preformed [2 x 21 and [3 x 31 square grids in the correct ratios
tion metal,[51and main group complexes.[61
generates an equilibrium solution giving the same NMR spectrum. The fact
Despite the abundance of research activity in this area, structhat the species has higher symmetry in solution (NMR spectroscopy) than in
the solid state (crystal structure analysis) may be attributed to fast exchange
tural reports detailing the manner in which the molecule + bulk
between the two rhombohedra1 enantiomers, as noted previously IS].
transformation occurs are scarce. Arnold et al. described the
1111 Yellow crystals were grown by slow diffusion of benzene into a solution of
Lewis base induced conversion of early transition metal seleno1.(CF,SO,), i n niti-omethane at 20 “C. Crystal data for {2[Ag6(2),(3)J
late and tellurolate complexes into selenide- and telluride-conlZ(O,SCF,) 2C,H;7H,CN02.1 C,H,,}: crystal size 0.1 x0.1 x 0 2 m m ;
STOE-IPDS diffractometer with graphite monochromater, T = - 80 “C,
taining molecules as the first step towards extended solids from
Ma,, radiation (i = 0.71073 8);monoclinic, space group P2/n, a = 29.961(6),
molecular precursors.’’] Piers and co-workers also detailed the
h = 21.534(4). 1’ = 38.827(8) 8, V = 25032(9) A’, 2 = 4, p = 1.128 mm-’,
reversible elimination of dialkyl tellurium from permethyl scanF(OO0) = 13092. period = 1.753 Mgm-’, M , = 6604.99.28,,, = 48”.The primadocene tellurolates to yield the dimeric telluride complex
ry structure was solved and refined by direct methods (SHELXS-92) [12]. All
non-hydrogen atoms except those of some heavily disordered solvent mole[(Cp:Sc),(p-Te)] (Cp* = C,Me,).[71 We set out to exploit this
cules were refined anisotropically (SHELXL-93) [13]. A riding model starting
reactivity to access high nuclearity metal telluride clusters. Here
from calculated positions was employed for the hydrogen atoms; due to disorwe report on the elimination of TePh, from the phosphaneder no hydrogen positions were calculated for solvent molecules. Of 107065
stabilized copper@)tellurolate 1, and its concomitant condensareflections measured 38400 were independent (R(int) = 0.0659), of which
38368 were employed in the refinement of 3795 parameters. Triflate ions and
tion to yield the mixed telluride/tellurolate cluster 2.
solvent molecules partially show heavy disorder, which could be successfully
[Cu,(p-TePh)(p3-TePh),(PEtPh,),] 1
modeled by use of geometry restraints (planarity, chemically equivalent 1,2-/
1$distances, and “anti-bumping” principles) and ADP restraints (rigid-bond,
similarity, and isotropy). 0,SCF; ions: restraints on S-0 (1.42A), S-C
(1.82 A), and C-F (1 32 A) bond lengths. For disordered triflate ions displaceCuCl readily dissolves in ethers with excess phosphane. When
ment parameters of fluorine and oxygen positions were equated for each split
a solution of CuCl and PPh,Et (1 :2) in THF/Et,O is allowed to
position by means of constraint. N-C and N - 0 distances in nitromethane
were fitted to target values of 1.55 and 1.20A. respectively; benzene molecreact with the silylated tellurium reagent Te(Ph)SiMe, ,a yellow,
ules were refined as variable metric groups; C-C bonds in n-hexane were fitted
homogenous
solution forms, from which yellow crystals of 1
to target values of 1.54 A. The structure was refined against F Z (full-matrixgrow in high yield (80-88 %) after layering with n-heptane
block least squares). Weighting scheme: w - ’ = a2(F?) (0.0939P)’
172.5727P, with P =: (F: + 2F,‘)/3, R1 = 0.0732 (F>4aF) and wR2 = 0.2146
[Eq.
The molecular structure of 1L9’(Figure 1) consists of
(all data). GOF ( F z = S ) =1.106, maximin residual density +2.34/
-1.25 e k ’ , (R1 = xllFol - ~ F J l / ~ ~ wFRJ2 ,= [)3v(F:
F,‘)2/x~,F31’2,
THFEGO
GOF = S = {I[w(F: - F,’)’]/(n - P ) } “ ~ , where n = no. of reflections, and
CuCl + 2 P E P 4 + Te(Ph)SiMe, -MqSiCI
[Cu,(TePh)6(PEPh,),] (a)
p = no. of parametei-s). Crystallographic data (excluding structure factors) for
the structures reported in this paper have been deposited with the Cambridge
1
Crystallographic Data Centre as supplementary publication no. CCDC100391. Copies of the data can be obtained free of charge on application to The
Director, CCDC. 12Union Road, Cambridge CBZlEZ, UK (fax: int.
a nonbonded octahedral array of tellurolate ligands (Te . . . Te
code +(1223) 336-033; e-mail: deposit(@chemcrys.cam.ac.uk).
that each bridge three Cu sites with the
4.035(1)-4.576(1)
[12] G. M. Sheldrick, Ac/a Crys/a/logr.Sect. A , 1990, 46, 467.
exception of Te3, which forms only two Cu-Te bonds. The
[13] G. M. Sheldrick, SHELXL-93, program for crystal structure refinement, Unip-TePh-Cu distances (av 2.560(1)
are noticeably shorter
versity of Gottingen. 1993.
[14] R. Krlmer, J.-M. Lehn, A. Marquis-Rigault, Proc. Natl. Acad. Sci. U S A 1993,
than their p 3 counterparts (2.577(1)-2.700(1), av 2.652(4)
90, 5394; D. P. Funeriu, Y.-B. He, H:J. Bister, J.-M. Lehn, Bull. Soc. Chim. Fr.
1996, 133, 673.
[I 51 Heterostrand helicates were obtained with pentacoordinate Cu” ions: B.
Hasenknopf, J.-M. Lehn, G. Baum, D. Fenske, Proc. Natl. Acad. Sci. USA
1996, 93, 1397.
+
+
-
~
A)
A)
A).
n
New Copper Telluride Clusters by Light-Induced
Tellurolate-Telluride Conversions””
J o h n F. Corrigan and Dieter Fenske*
There is currentlv considerable interest in the chemistry of
metal selenolate and tellurolate complexes,[” driven in part by
their potential utility as single-source precursors for semicon[*I Prof. Dr D. Fenske, Dr. J. F Corrigan
Institut fur Anorganische Chemie der Universitat
Engesserstrasse, Geb. Nr. 30.45. D-76128 Karlsruhe (Germany)
Fax. Int. code (721)661-921
e-mail john@ achibm6.chemie.uni-karlsruhe.de
[**I This work was supported by the the Deutsche Forschungsgemeinschaft
(SFB 195). the Fonds der Chemischen industrie, and the European Union
(HCM program) J. F. C. thanks the Natural Sciences and Engineering Research Council (Canada) for a postdoctoral fellowship.
Angew Chem In/ Ed EizgI 1997, 36, No 18
Figure 1. Molecular structure of 1 in thecrystal. Important bond lengths and angles
are discussed in the text. Te atoms are illustrated as dark spheres. and Cu atoms as
spheres with horizontal hashing.
0 WILEY-VCH Verlag GmbH, D-69451 Welnheim, 1997
0570-0833/97/3618 1981 $ 1 7 50+ S0,O
1981
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