Two new high-nuclearity copper(II) chloride oligomers with herringbone stacking patterns synthesized by in situ temptation

Article abstract of DOI:10.1139/V05-237

The use of trichloroiminophosphoranes Cl₃P=NR to control the concurrent release of the templating cation [RNH₃]⁺ and chloride ligand via in situ P-N and P-Cl bond cleavage produced two new copper(II) chloride oligomers. The nature of the organic substituent R was a factor in determining the chain lengths. For n-propyltrichloroiminophosphorane, the hexanuclear cluster [n-PrNH₃]₂[Cu₆Cl ₁₄] (1) was obtained, while p-tolyltrichloroiminophosphorane generated the tetranuclear copper chloride salt [4-CH₃C ₆H₄NH₃][2-Cl-4-CH₃C ₆H₃NH₃][Cu₄Cl₁₀] (2). In both structures a two-dimensional framework displaying a herringbone arrangement is created by Cu-Cl secondary bonding interactions. The direct addition of the [n-PrNH₃]⁺ cation to a CuCl₂·2H ₂O solution under the same reaction conditions produced [n-PrNH ₃]₂[CuCl₄].

Full text of DOI:10.1139/V05-237

140
Two new high-nuclearity copper(II) chloride
oligomers with herringbone stacking patterns
synthesized by in situ templation1
Zhiyong Fu and Tristram Chivers
Abstract: The use of trichloroiminophosphoranes Cl3P=NR to control the concurrent release of the templating cation
[RNH3]+ and chloride ligand via in situ P—N and P—Cl bond cleavage produced two new copper(II) chloride oligo-
mers. The nature of the organic substituent R was a factor in determining the chain lengths. For n-propyltrichloro-
iminophosphorane, the hexanuclear cluster [n-PrNH3]2[Cu6Cl14] (1) was obtained, while p-tolyltrichloroiminophosphorane
generated the tetranuclear copper chloride salt [4-CH3C6H4NH3][2-Cl-4-CH3C6H3NH3][Cu4Cl10] (2). In both structures a
two-dimensional framework displaying a herringbone arrangement is created by Cu—Cl secondary bonding interactions.
The direct addition of the [n-PrNH3]+ cation to a CuCl2·2H2O solution under the same reaction conditions produced [n-
PrNH3]2[CuCl4].
Key words: copper halides, templation, oligomers, two-dimensional frameworks.
Résumé : L’utilisation de trichloroiminophosphoranes Cl3P=NR pour contrôler la libération simultanée du cation
[RNH3]+ servant de gabarit et le ligand chlorure par le biais d’un clivage in situ de liaisons P—N et P—Cl conduit à
la formation de deux nouveaux oligomères du chlorure de cuivre(II). La nature du substituant organique R est un fac-
teur dans la détermination des longueurs des chaînes. Avec le n-propyltrichloroiminophosphorane, il y a formation de
l’agrégat hexanucléaire [n-PrNH3]2[Cu6Cl14] (1) alors que le p-tolyltrichloroiminophosphorane génère la formation du
chlorure de cuivre tétranucléaire [4-CH3C6H4NH3][2-Cl-4-CH3C6H3NH3][Cu4Cl10] (2). Dans les deux structures, il y a
création d’un squelette bidimensionnel comportant un arrangement en chevrons formé par des interactions de liaisons
secondaires Cu—Cl. L’addition directe du cation [n-PrNH3]+ à une solution de CuCl2·2H2O dans les mêmes conditions
réactionnelles conduit à la formation de [n-PrNH3]2[CuCl4].
Mots clés : halogénures de cuivre, gabarit, oligomères, squelettes bidimensionnels.
[Traduit par la Rédaction] Fu and Chivers 145
Introduction
nonstereospecific bridging capability of the halide ions al-
low the formation of secondary bonding interactions (SBIs)
between the oligomers, which give rise to various stacking
patterns (17).
The use of templating reagents is a common technique in
the synthesis of inorganic materials (1, 2). This method em-
ploys a cation, e.g., alkylammonium [RNH3]+, to provide
charge balance and to regulate the structural arrangement of
anionic frameworks through forces such as hydrogen bond-
ing or van der Waals repulsion (3). The traditional procedure
for the synthesis of oligomeric copper(II) halide frameworks
involves mixing the copper(II) halide with an appropriate or-
ganic cation in a concentrated hydrohalic acid solution (4–
6). Willett and co-workers (7–9) have used this approach to
produce many copper halide oligomers with fascinating
structural features and interesting physical properties. Much
of their work has focused on the characterization of quasi-
planar bibridged CunX2n+2 systems (n = 2–7, 10) (10–16).
The “softness” of the copper coordination sphere and the
Recently, some new open-framework zinc phosphates
were prepared under solvothermal conditions by using P—N
bond cleavage in hexamethylphosphoramide OP(NMe2)3 to
control the simultaneous release of an organic amine and
phosphoric acid (18). As part of our investigations of novel
inorganic materials, we are particularly interested in the in
situ templation synthesis of new copper(II) halide frame-
works. In addition to generating new functional compounds,
this indirect templation method may contribute to an under-
standing of the mechanism of network formation. For exam-
ple, we have shown that the tris(alkylamido)phosphate
OP[N(H)-t-Bu]3 functions both as an indirect source of the
templating [t-BuNH3]+ cation and as a proton acceptor in the
Received 7 July 2005. Published on the NRC Research Press Web site at http://canjchem.nrc.ca on 22 February 2006.
Dedicated to Dr Arthur Carty for his outstanding contributions to Canadian science.
Z. Fu and T. Chivers.2 Department of Chemistry, University of Calgary, Calgary, AB T2N 1N4, Canada.
1This article is part of a Special Issue dedicated to Professor Arthur Carty.
2Corresponding author (e-mail: chivers@ucalgary.ca).
Can. J. Chem. 84: 140–145 (2006)
doi:10.1139/V05-237
© 2006 NRC Canada

Fu and Chivers
141
Table 1. Crystal data and structure refinement for 1, 2, and 3.
1
2
3
Empirical formula
C6H20Cl14Cu6N2
C14H19Cl11Cu4N2
C7H9Cl2N
fw (g)
997.78
859.42
178.05
T (K)
298(2)
298(2)
298(2)
Crystal system
Space group
a (Å)
b (Å)
c (Å)
Monoclinic
P21/c
Monoclinic
P21/c
Monoclinic
P21/c
9.3454(19)
6.0319(12)
24.159(5)
97.79(3)
1349.3(5)
2
13.031(3)
6.1151(12)
17.191(3)
95.66(3)
1363.1(5)
2
5.2178(10)
8.6191(17)
18.111(4)
97.40(3)
807.7(3)
4
β (°)
V (Å3)
Z
Dcalcd (g cm–3)
2.456
2.094
1.464
µ (mm–1)
F(000)
6.032
964
4.165
840
0.724
368
θmin–θmax (°)
3.78–27.50
4644
3075
0.0331
1.033
0.0393, 0.0804
3.14–25.02
8189
2362
0.0537
1.101
0.0521, 0.1460
2.62–25.03
1667
1154
0.0426
1.067
0.0673, 0.1676
0.0815, 0.1786
0.521, –0.556
Reflections collected
Independent reflections
R(int)
Goodness-of-fit on F2
Final R indices [I > 2σ(I)]; R1, wR2
R indices (all data); R1, wR2
Largest diff. peak and hole (e Å–3)
0.0656, 0.0907
0.732, –0.638
0.0654, 0.1568
0.786, –0.890
production of a novel copper chloride structural motif that is
different from the network synthesized by the direct addition
of [t-BuNH3]Cl (19). In the current work we have investi-
gated the use of trichloroiminophosphoranes Cl3P=NR (R =
n-Pr, p-tolyl) as an in situ source of both the organic ammo-
nium cation and the Cl– ligand in the formation of novel
copper halide frameworks. We report here the formation and
X-ray structures of two high-nuclearity copper chloride oli-
gomers [n-PrNH3]2[Cu6Cl14] (1) and [4-CH3C6H4NH3][2-Cl-
4-CH3C6H3NH3][Cu4Cl10] (2), both of which exhibit a her-
ringbone structure. For the quasi-planar bibridged CunX2n+2
oligomers, this stacking pattern has only been reported in the
pentanuclear cluster [Cu5Cll0(n-C3H7OH)2] (20). For com-
parison, the direct addition of [n-PrNH3]+ to a CuCl2·2H2O
solution under the same reaction conditions produced the
known copper chloride complex [n-PrNH3]2[CuCl4] (21).
The structure of [2-Cl-4-CH3C6H3NH3]+Cl– (3), a by-product
of the reaction involving Cl3P=N-p-tolyl, is also reported.
23 °C, and yellow crystals of 1 (0.020 g, 12%) were isolated
from the yellow precipitate manually.
Syntheses of 2 and 3
A mixture of copper chloride dihydrate (0.170 g,
1.00 mmol), p-tolyltrichloroiminophosphorane (0.243 g,
1.00 mmol), water (0.054 g, 3.00 mmol), and 10 mL toluene
were placed in a sealed 23 mL Teflon vessel and heated at
90 °C for 12 h. The reaction vessel was allowed to cool to
23 °C. Yellow crystals of 2 (0.040 g, 18%) and a few pale
yellow crystals of 3 were separated from the black precipi-
tate manually.
X-ray structural analyses
Suitable crystals of the complexes (1, yellow block
(0.18 × 0.12 × 0.12 mm3); 2, yellow plate (0.20 × 0.04 ×
0.04 mm3); 3, pale yellow plate (0.24 × 0.08 × 0.08 mm3))
were selected, coated with oil (Paratone 8277, Exxon),
and mounted on glass fibres. The measurements were made
on a Nonius KappaCCD diffractometer with graphite-
monochromated Mo Kα radiation. Data were collected at
25 °C, using the ω and φ scans to a maximum θ value of
27.5°, 25.02°, and 25.03° for 1, 2, and 3, respectively. The
data were corrected for Lorentz and polarization effects and
for absorption using the multiscan method (23). Since the
crystals did not show any sign of decay during data collec-
tion, a decay correction was deemed unnecessary. The struc-
tures were solved by direct methods SHELXS-97 (24). The
C atoms of the n-propyl groups in 1 were disordered over
three positions with unequal site occupancy factors in an ap-
proximate ratio of 2:1:1; the C3 and C2a atoms were also
disordered at the same position in a 1:1 ratio. In 2, the cat-
ions [4-CH3C6H4NH3] and [2-Cl-4-CH3C6H3NH3] were dis-
ordered at the same position with equal site occupancy
Experimental section
Reagents and general procedures
n-Propyltrichloroiminophosphorane and 4-tolyltrichloro-
iminophosphorane were prepared according to the literature
procedure (22). Tetrachloroethane was dried over CaH2 and
fractionally distilled. Copper chloride dihydrate, phosphorus
pentachloride, and chlorobenzene were used as received.
Synthesis of 1
A mixture of copper chloride dihydrate (0.170 g,
1.00 mmol), n-propyltrichloroiminophosphorane (0.194 g,
1.00 mmol), water (0.054 g, 3.00 mmol), and 10 mL toluene
were placed in a sealed 23 mL Teflon vessel and heated at
90 °C for 12 h. The reaction vessel was allowed to cool to
© 2006 NRC Canada

142
Can. J. Chem. Vol. 84, 2006
Scheme 1.
Cl
Cl
Cl
P
N
R
R = n-Pr
[n-PrNH3]2[Cu6Cl14] (1)
CuCl2·2H2O
H2O
-
+
+
Cl
RNH3
R = p-tolyl
[4-CH3C6H4NH3][2-Cl-4-CH3C6H3NH3][Cu4Cl10] (2)
factors. All non-hydrogen atoms were refined anisotropically
except the disordered atoms. All the hydrogen atoms were
included at geometrically idealized positions. Crystallo-
graphic data for 1, 2, and 3 are summarized in Table 1. Ad-
ditional data are available in the Supporting information.3
CH3C6H4NH3]+ cation during the solvothermal process. The
chloride salt [2-Cl-4-CH3C6H3NH3]+Cl– (3) was also isolated
from the reaction products and characterized by X-ray crys-
tallography (vide infra). A similar observation has been re-
ported for the bromination of the 3-chloroanilinium cation
by CuBr2 in HBr solution to give the 6-bromo-3-chloro-
anilinium cation (26).
Results and discussion
The direct reaction of [n-PrNH3]Cl and CuCl2·2H2O un-
der the solvothermal conditions employed for the synthesis
of 1 generated the known mononuclear anion [CuCl4]– (21)
as the [n-PrNH3]+ salt, demonstrating the structure-directing
effect of the indirect templation method, as previously re-
ported for the generation of a novel anionic copper halide
framework by in situ templation employing [t-BuNH3]+,
which is provided by the amidophosphate reagent OP(NH-t-
Bu)3] (19). Interestingly, the outcome of the indirect
templation method is sensitive to reaction conditions, nota-
bly the polarity of the solvent. When the reaction of
Cl3P=N-n-Pr with CuCl2·2H2O takes place in ethanol at
90 °C, the final product is [n-PrNH3]2[CuCl4]. This differ-
ence may be attributable to the faster rate of hydrolysis of
Cl3P=N-n-Pr in the more polar solvent ethanol compared
with that in toluene. The rapid cleavage of P—Cl and P—N
bonds apparently results in a templation effect similar to that
observed for the direct addition of Cl– and [n-PrNH3]+ (in
the form of the salt [n-PrNH3]Cl).
The products obtained from the solvothermal reactions of
trichloroiminophosphoranes Cl3P=NR with CuCl2·2H2O in
toluene at 90 °C exhibit distinctly different structural motifs
depending on the identity of the R group (Scheme 1). In the
case of R = n-Pr, the hexanuclear copper chloride chain
[Cu6Cl14]2– is isolated as the [n-PrNH3]+ salt, whereas for
the aryl subsituent (R = p-tolyl), the tetranuclear [Cu4Cl10]2–
fragment is obtained in conjunction with the [4-
CH3C6H4NH3]+ and [2-Cl-4-CH3C6H3NH3]+ cations. The
chloride ions in these syntheses are generated by in situ hy-
drolysis of the P—Cl bonds in Cl3P=NR, which is achieved
by the addition of a stoichiometric amount of water to the
reaction mixture. Concomitantly, the in situ generated
organoammonium cations [RNH3]+ exhibit an indirect
templation function in the generation of these anionic copper
halide frameworks. The formation of bibridged CunX2n+2 oli-
gomers in previous reports is viewed to involve fragments
cut from infinite CuX2 chains by charge-compensating cat-
ions acting as “molecular scissors” (10, 12). The weak inter-
action between the Cl– ion and the cation results in the
termination of the CuX2 chains. This is a common modifica-
tion in the formation of copper halide oligomers. In the new
synthesis described herein the copper chloride oligomers are
built up by replacement of the aqua ligands in the
CuCl2·2H2O monomer (25) by the stronger chloride ligands
provided by the hydrolysis of Cl3P=NR. The formation of
the new cation [2-Cl-4-CH3C6H3ClNH3]+ in the synthesis of
2 presumably occurs by the chlorination of the [4-
Complexes 1 and 2 were identified by single-crystal X-ray
analyses (Tables 2 and 3). As illustrated in Fig. 1, compound
1 contains an anionic hexanuclear copper chloride oligomer
with a different stacking pattern from that found in
[C7H10N]2[Cu6Cl14] (11). In 1, the [Cu6Cl14]2– dianion con-
nects to four neighbours of adjacent stacks via two long
Cu—Cl bonds (Cl2—Cu2c = 2.6266(12) Å) and two Cu—Cl
secondary
bonding
interactions
(Cl2—Cu1d
=
2.8080(13) Å), which extend the structure to a 2D herring-
bone motif. By contrast, the stacks of oligomers in
3 Supplementary data for this article are available on the journal Web site (http://canjchem.nrc.ca) or may be purchased from the Depository
of Unpublished Data, Document Delivery, CISTI, National Research Council Canada, Ottawa, ON K1A 0R6, Canada. DUD 4081. For more
information on obtaining material refer to http://cisti-icist.nrc-cnrc.gc.ca/irm/unpub_e.shtml. CCDC 277576 (1), 277577 (2), and 277578 (3)
contain the crystallographic data for this manuscript. These data can be obtained, free of charge, via www.ccdc.cam.ac.uk/conts/retriev-
ing.html (Or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax +44 1223 336033; or de-
posit@ccdc.cam.ac.uk).
© 2006 NRC Canada

Fu and Chivers
143
Table 2. Selected bond lengths (Å) and bond angles (°) for 1.
Bond lengths (Å)
Cu(3)—Cl(6)
Cu(3)—Cl(7)
Cu(3)—Cl(7a)
Cu(3)—Cl(5)
Cu(1)—Cl(1)
Cu(1)—Cl(2)
Cu(1)—Cl(4)
Cu(1)—Cl(3)
2.2631(13)
2.2674(13)
2.2809(12)
2.2880(12)
2.2581(14)
2.2723(12)
2.3116(12)
2.3381(13)
Cu(2)—Cl(4)
Cu(2)—Cl(3)
Cu(2)—Cl(6)
Cu(2)—Cl(5)
Cu(2)—Cl(2b)
Cl(2)—Cu(2c)
Cl(7)—Cu(3a)
Cl(2)—Cu(1d)
2.2674(13)
2.2807(12)
2.2933(12)
2.3070(13)
2.6266(12)
2.6266(12)
2.2809(12)
2.8080(13)
Bond angles (°)
Cl(6)-Cu(3)-Cl(7)
Cl(6)-Cu(3)-Cl(7a)
Cl(7)-Cu(3)-Cl(7a)
Cl(6)-Cu(3)-Cl(5)
Cl(7)-Cu(3)-Cl(5)
Cl(7a)-Cu(3)-Cl(5)
Cl(1)-Cu(1)-Cl(2)
Cl(1)-Cu(1)-Cl(4)
Cl(2)-Cu(1)-Cl(4)
Cl(1)-Cu(1)-Cl(3)
Cl(2)-Cu(1)-Cl(3)
Cl(4)-Cu(1)-Cl(3)
Cl(4)-Cu(2)-Cl(3)
Cl(4)-Cu(2)-Cl(6)
179.47(5)
92.72(4)
87.28(4)
86.73(4)
93.29(4)
177.93(5)
96.52(5)
88.95(4)
170.83(4)
172.53(5)
89.69(4)
84.37(4)
86.71(4)
92.42(4)
Cl(3)-Cu(2)-Cl(6)
Cl(4)-Cu(2)-Cl(5)
Cl(3)-Cu(2)-Cl(5)
Cl(6)-Cu(2)-Cl(5)
Cl(4)-Cu(2)-Cl(2b)
Cl(3)-Cu(2)-Cl(2b)
Cl(6)-Cu(2)-Cl(2b)
Cl(5)-Cu(2)-Cl(2b)
Cu(3)-Cl(6)-Cu(2)
Cu(3)-Cl(5)-Cu(2)
Cu(2)-Cl(4)-Cu(1)
Cu(2)-Cl(3)-Cu(1)
Cu(1)-Cl(2)-Cu(2c)
Cu(3)-Cl(7)-Cu(3a)
170.30(4)
167.35(4)
93.16(4)
85.58(4)
95.25(4)
97.72(4)
91.98(4)
97.30(4)
94.07(5)
93.04(4)
94.51(5)
93.45(4)
97.54(4)
92.72(4)
Note: Symmetry transformations used to generate equivalent atoms: a = –x – 1, –y + 1, –z; b = x, y – 1, z;
c = x, y + 1, z; d = –1 – x, 1/2 + y, 1/2 – z.
Table 3. Selected bond lengths (Å) and bond angles (°) for 2.
Bond lengths (Å)
Cu(2)—Cl(3)
Cu(2)—Cl(5)
Cu(2)—Cl(4)
Cu(2)—Cl(5a)
Cu(2)—Cl(2b)
Cu(1)—Cl(1)
2.2743(18)
2.2846(18)
2.2897(16)
2.2975(16)
2.6764(17)
2.237(2)
Cu(1)—Cl(2)
Cu(1)—Cl(4)
Cu(1)—Cl(3)
Cl(5)—Cu(2a)
Cl(2)—Cu(2c)
Cl(2)—Cu(1d)
2.2589(17)
2.3143(18)
2.3187(17)
2.2975(16)
2.6764(17)
3.0724(18)
Bond angles (°)
Cl(3)-Cu(2)-Cl(5)
Cl(3)-Cu(2)-Cl(4)
Cl(5)-Cu(2)-Cl(4)
Cl(3)-Cu(2)-Cl(5a)
Cl(5)-Cu(2)-Cl(5a)
Cl(4)-Cu(2)-Cl(5a)
Cl(3)-Cu(2)-Cl(2b)
Cl(5)-Cu(2)-Cl(2b)
Cl(4)-Cu(2)-Cl(2b)
Cl(5a)-Cu(2)-Cl(2b)
170.35(7)
85.68(6)
93.02(6)
92.79(6)
86.87(6)
170.29(6)
94.48(7)
95.18(6)
97.97(6)
91.71(6)
Cl(1)-Cu(1)-Cl(2)
Cl(2)-Cu(1)-Cl(4)
Cl(1)-Cu(1)-Cl(3)
Cl(2)-Cu(1)-Cl(3)
Cl(4)-Cu(1)-Cl(3)
Cu(2)-Cl(5)-Cu(2a)
Cu(2)-Cl(4)-Cu(1)
Cu(2)-Cl(3)-Cu(1)
Cu(1)-Cl(2)-Cu(2c)
95.53(8)
92.10(7)
89.37(7)
169.85(7)
84.11(6)
93.13(6)
94.41(6)
94.70(6)
99.70(6)
Note: Symmetry transformations used to generate equivalent atoms: a = –x – 4, –y – 3, –z – 2; b = x, y +
1, z; c = x, y – 1, z; d = –4 – x, –1/2 + y, –3/2 – z.
[C7H10N]2[Cu6Cl14] are interlocked to give a layer pattern
parallel to the ab plane. Each copper centre in 1 is coordi-
nated to four chloride ligands. All the copper ions protrude
from the ligand plane, displaying a square pyramidal distor-
tion. The central Cu3 atom shows the smallest distortion
with a dihedral angle of 2.0° between the Cl7-Cu3-Cl5 and
Cl7a-Cu3-Cl6 planes. The most significant deviation from
the square plane is observed at the Cu2 center with a dihedral
angle of 16.3° between the Cl5-Cu2-Cl3 and Cl6-Cu2-Cl4
planes. The terminal Cu1 atom has a dihedral angle of 8.0°
between the Cl4-Cu1-Cl1 and Cl3-Cu1-Cl2 planes. The ter-
minal copper(II)—chloride bond lengths are 2.2581(14)
(Cu1—Cl1) and 2.2723(12) Å (Cu1—Cl2), whereas the
bridging copper(II)—chloride bond lengths are 2.3381(13) Å
© 2006 NRC Canada

144
Can. J. Chem. Vol. 84, 2006
Table 4. Bond lengths (Å) and bond angles (°) for 3.
Fig. 1. Molecular structure and atomic numbering scheme for 1.
Thermal ellipsoids are shown at the 70% level.
Bond lengths (Å)
Cl(1)—C(4)
C(7)—C(6)
1.719(5)
1.379(7)
1.396(8)
1.387(7)
1.454(7)
C(5)—C(3)
C(4)—C(2)
C(3)—C(2)
C(3)—C(1)
1.397(8)
1.394(8)
1.399(8)
1.497(8)
Cl2
Cl3
Cl5
Cl7
Cl6a
Cl1a
Cl4a
C(7)—C(5)
C(6)—C(4)
C(6)—N(1)
Cu1 N1
Cl1
Cu2
Cu3
Cu3a
Cu2a
Cu1a
N1a
Cl4
Cl6
Cl7a
Cl5a
Cl3a
Cl2a
Bond angles (°)
C(6)-C(7)-C(5)
C(7)-C(6)-C(4)
C(7)-C(6)-N(1)
C(4)-C(6)-N(1)
C(3)-C(5)-C(7)
C(2)-C(4)-C(6)
120.5(5)
119.3(5)
120.6(4)
120.2(4)
121.1(5)
120.4(5)
C(2)-C(4)-Cl(1)
C(6)-C(4)-Cl(1)
C(5)-C(3)-C(2)
C(5)-C(3)-C(1)
C(2)-C(3)-C(1)
C(4)-C(2)-C(3)
118.0(4)
121.6(4)
117.6(5)
121.8(5)
120.6(5)
121.1(5)
Fig. 2. Molecular structure and atomic numbering scheme for 2.
Thermal ellipsoids are shown at the 50% level.
Cl6a
Cl2
Cu1
N3a
Cl4
Fig. 3. Molecular structure and atomic numbering scheme for the
cation in 3. Thermal ellipsoids are shown at the 50% level.
Cl5
Cl3a
Cu1a
Cl4a
Cl1a
Cu2
N3
Cl1
Cu2a
Cl1
Cl6
Cl3
Cl5a
Cl2a
C4
C3
C2
C1
N1
C5
C6
(Cu1—Cl3), 2.3116 Å (Cu1—Cl4), 2.2674(13) Å (Cu2—
Cl4), 2.2807(12) Å (Cu2—Cl3), 2.3070(13) Å (Cu2—Cl5),
2.2933(12) Å (Cu2—Cl6), 2.2880(12) Å (Cu3—Cl5),
2.2631(13) Å (Cu3—Cl6), 2.2809 (12) Å (Cu3—Cl7a), and
2.2674(13) Å (Cu3—Cl7), respectively. These values are in
agreement with the rule of variations in in-plane bond
lengths of bibridged CunX2n+2 oligomers, demonstrating a
short-long-short··· alternation for the t-b1-b2··· sequence.4
The bridging Cu-Cl-Cu bond angles range from 94.51° for
the terminal fragment to 92.72° for the central units.
The structural characteristics of compound 2 are similar to
those of 1 except that the anion is tetranuclear (Fig. 2). The
[Cu4Cl10]2– fragment in [Me4N]2[Cu4Cl10] has the same
stacking pattern as that in 2, but with a different mode of an-
ion–cation interactions. In 2, the oligomer is linked to four
neighbours of adjacent stacks (Cl2—Cu2c = 2.6764(17) Å,
Cl2—Cu1d = 3.0724(18) Å), whereas in [Me4N]2[Cu4Cl10]
the influence of the cations restricts these interactions to two
neighbours (12). The Cu1 atom in 2 displays a small tetrahe-
dral distortion, while the Cu2 atom exhibits a square pyrami-
dal distortion with a dihedral angle of 14.0° between the
Cl4-Cu2-Cl5 and Cl3-Cu2-Cl5a planes. The terminal Cl1
and Cl2 ligands coordinate with the Cu1 atom (Cu1—Cl1 =
2.237(2) Å, Cu1—Cl2 = 2.2589(17) Å), whereas the bridg-
ing ligands Cl3, Cl4, and Cl5 connect the adjacent copper at-
oms with a mode (Cu1—Cl3 = 2.3187(17) Å, Cu1—Cl4 =
2.3143(18) Å, Cu2—Cl3 = 2.2743(18) Å, Cu2—Cl4 =
2.2897(16) Å, and Cu2—Cl5 = 2.2846(18) Å). These values
are typical and show the short-long-short alternation ob-
served for 1. The bridging Cu-Cl-Cu bond angles vary from
94.70° to 93.13°.
C7
+
chlorination occurred in the position ortho to the NH3
group to give the [2-Cl-4-CH3C6H3NH3]+ cation (Fig. 3).
The bond lengths and bond angles in this cation (C—Cl =
1.719(5) Å, C6—N1 = 1.454(7) Å; C2-C4-Cl1 = 118.0(4)°,
C6-C4-Cl1 = 121.6(4)°) are similar to those reported for the
related anilinium cation, [3-Cl-6-BrC6H3NH3]+ (26).
As illustrated in Fig. 4, the structures of 1 and 2 are both
extended into two-dimensional networks by SBIs that give
rise to a herringbone motif. The terminal chloride ligand Cl2
in 1 acts as a µ2 bridge connecting to the copper centres lo-
cated in the adjacent fragments. The Cu1 and Cu2 atoms
adopt a 4+1+1 coordination mode, while the Cu3 atom has a
4+2 coordination geometry, in which the secondary bonding
interactions for Cu1, Cu2, and Cu3 are 2.808 and 3.008 Å,
2.627 and 3.213 Å, and 2.981 and 2.960 Å, respectively. In
compound 2, the Cu1 atom adopts a 4+2 coordination mode
with SBIs of 3.072 and 3.127 Å. The Cu2 atom has a 4+1+1
coordination mode with SBIs of 2.676 and 3.194 Å. The
stacking patterns of 1 and 2 are denoted as 6(3/2, 1/2) and
4(3/2, 1/2), respectively, according to the notation of Willett
and co-workers (17). Like most bibridged CunX2n+2 oligo-
mers, the charge-compensating cations [n-PrNH3]+ in 1 and
[2-Cl-4-CH3C6H3NH3]+ and [4-CH3C6H4NH3]+ in 2 form
hydrogen bonds with a pair of trans terminal chloride lig-
ands (N—Cl = 3.245 Å for 1 and 3.253 Å for 2).
In summary, a new synthetic approach involving the si-
The X-ray analysis of compound 3 (Table 4) revealed that
multaneous in situ generation of Cl– and [RNH3]+ ions for
4 The Ith Cu—Cl bond length is denoted by bI, starting from the terminal atom; b = bridging, t = terminal (27).
© 2006 NRC Canada

Fu and Chivers
145
Fig. 4. Packing diagrams of compounds 1 and 2. The Cu—Cl
secondary bonding interactions are represented by broken lines.
References
1. A.K. Cheetham, G. Férey, and T. Loiseau. Angew. Chem. Int.
Ed. 38, 3268 (1999).
2. J.D. Martin, A.M. Dattelbaum, T.A. Thornton, R.M. Sullivan,
J. Yang, and M.T. Peachey. Chem. Mater. 10, 2699 (1998).
3. C.N.R. Rao, S. Natarajan, and S. Neeraj. J. Am. Chem. Soc.
122, 2810 (2000).
1
4. M. Wei, R.D. Willett, D. Teske, K. Subbaraman, and J.E.
Drumheller. Inorg. Chem. 35, 5781 (1996).
5. S. Haddad and R.D. Willett. Inorg. Chem. 40, 809 (2001).
6. C. Horn, I. Dance, D. Craig, M. Scudder, and G. Bowmaker. J.
Am. Chem. Soc. 120, 10549 (1998).
7. M. Wei, R.D. Willett, and C.J. Gómez-García. Inorg. Chem.
43, 4534 (2004).
8. M. Wei and R.D. Willett. Inorg. Chem. 35, 6381 (1996).
9. M. Wei, R.D. Willett, and K.W. Hipps. Inorg. Chem. 35, 5300
(1996).
10. S. Haddad, F. Awwadi, and R.D. Willett. Cryst. Growth Des.
3, 501 (2003).
11. M.R. Bond, H. Place, Z. Wang, R.D. Willett, Y. Liu, T.E.
Grigereit, J.E. Drumheller, and G.F. Tuthill. Inorg. Chem. 34,
3134 (1995).
12. K.E. Halvorson, T. Grigereit, and R.D. Willett. Inorg. Chem.
26, 1716 (1987).
2
13. T.E. Grigereit, B.L. Ramakrishna, H. Place, R.D. Willett, G.C.
Pellacani, T. Manfredini, L. Menabue, A. Bonomartini-
Corradi, and L.P. Battaglia. Inorg. Chem. 26, 2235 (1987).
14. A. Colombo, L. Menabue, A. Motori, G.C. Pellacani, W. Porzio,
F. Sandrolini, and R.D. Willett. Inorg. Chem. 24, 2900 (1985).
15. R. Fletcher, J.J. Hansen, J. Livermore, and R.D. Willett. Inorg.
Chem. 22, 330 (1983).
16. M.R. Bond, R.D. Willett, R.S. Rubins, P. Zhou, C.E. Zaspel,
S.L. Hutton, and J.E. Drumheller. Phys. Rev. B, 42, 10280
(1990).
17. U. Geiser, R.D. Willett, M. Lindbeck, and K. Emerson. J. Am.
Chem. Soc. 108, 1173 (1986).
18. S. Neeraj and A.K.Cheetham. Chem. Commun. (Cambridge),
1738 (2002).
19. T. Chivers, Z. Fu, and L.K. Thompson. Chem. Commun.
(Cambridge, U.K.), 2339 (2005).
20. R.D. Willett and R.E. Rundle. J. Chem. Phys. 40, 838 (1964).
21. (a) B. Doudin and G. Chapuis. Acta Crystallogr. Sect. B, 46,
175 (1990); (b) B. Doudin and G. Chapuis. Acta Crystallogr.
Sect. B, 46, 180 (1990).
22. S.A. Bell, T.Y. Meyer, and S.J. Geib. J. Am. Chem. Soc. 124,
10698 (2002).
23. Z. Otwinowski and W. Minor. Methods Enzymol. 276, 307
(1997).
24. G.M. Sheldrick. SHELXS-97 [computer program]. University
of Göttingen, Göttingen, Germany. 1997.
25. M. Kakiuchi, T. Abe, and H. Nakayama, Geochem. J. 35, 285
(2001).
26. R.D. Willett. Inorg. Chem. 40, 966 (2001).
27. R.D. Willett. Acta Crystallogr. Sect. B, 44, 503 (1988).
the production of anionic copper chloride oligomers is intro-
duced in this study. Variation of the R group in the precur-
sors Cl3P=NR creates different lengths of the anionic chains.
The structures of both oligomers exhibit a herringbone
stacking pattern. These findings provide another example of
the generation of new inorganic structural frameworks via
indirect templation using P-N reagents (18, 19). There is
considerable scope for the construction of novel inorganic
architectures via variation in reaction conditions in these
solvothermal processes, as indicated by the influence of sol-
vent polarity in the current work.
Acknowledgements
We thank the Alberta Ingenuity Fund and the Natural Sci-
ences and Engineering Research Council of Canada
(NSERC) for financial support.
© 2006 NRC Canada