B. Li et al. / Journal of Organometallic Chemistry 745-746 (2013) 173e176
175
crystals of 2 were deposited in about 45% yield. Anal. Calcd for
14H7Ag4F9N2O6 (901.70): C 18.65, H 0.78, N 3.11%. Found: C 18.73,
C
H 0.69, N 3.21%.
2.2. X-ray crystallographic analysis
Selected crystals were used for data collection on OXFORD
Diffraction Gemini Single Crystal diffractometer equipped with
ꢁ
graphite monochromatized Mo-K
a
radiation (
l
¼ 0.71073 A) at
room temperature using the
u
-scan technique. An empirical ab-
sorption correction was applied using the SADABS program [18].
The structures were solved by the direct method and refined by full
matrix least squares on F2 usiꢂng the SHELXTL program package [19].
The CF3 moieties of CF3CO2 groups in compound 1 were disor-
dered, and the SADI command was used to fix them in the re-
finements. The crystal data and details of refinement are
summarized in Table 1.
3. Results and discussion
3.1. [(AgL)(AgCF3CO2)4(H2O)2] (1)
The asymmetric unit of 1 contains five crystallographically
independent Ag(I) ions, four trifluoroacetate ions, and two co-
ordinated water molecules. As shown in Fig. 1a, the ethynide
group (C1^C2) is enveloped by an unprecedented m6
-
-
h1 h1 h1 h1 h2 h2 coordination mode. Utilizing three m2-O,O0, m3
, , , , ,
O,O0,O0 and m4-O,O,O0,O0 (O5, O6, O3, O3, O4 and O1, O1, O2, O2)
trifluoroacetate groups as linkage components, together with the
ꢁ
argentophilic interactions (Ag1eAg2 3.048(14)A), the external
silver atom Ag1 is hitched to the Ag6 basket, within which the
argentophilic AgeAg distances vary from 2.822(13) to 3.269(15)
ꢁ
A, being shorter than twice the van der Waals radius of silver
ꢁ
ions (3.44 A) [20] and suggesting the presence of significant
argentophilic interactions. Adjacent Ag6 baskets are coalesced by
sharing Ag3 and Ag3#2 to yield an Ag10 aggregate (Fig. 1b). Such
Ag10 aggregates are linked by three pairs of trifluoroacetate
groups (O5eO6, O3eO4 and O1eO2) via m2-O,O0, m3-O,O0,O0 and
m4-O,O,O0,O0 coordination modes, respectively, with the assis-
tance of the argentophilic interactions (Ag1eAg2, Ag1#3ꢂAg2#3
ꢁ
3.048(14)A), to generate an infinite column along the a axis. The
infinite columns are interconnected by the remaining tri-
fluoroacetate group (O7eO8) via m2-O,O0 coordination mode to
form a two-dimensional coordination polymer parallel to the ac
plane. There are also relatively weak hydrogen bonds O1WeHꢀO4
Fig. 2. (a) Atom labeling and coordination mode of L in 2 (50% thermal ellipsoids are
drawn for silver atoms). (b) View of Ag8 aggregate. (c) Ag8 aggregates are fused
together through trifluoroacetate groups to give rise to a silver column in 2 along the
b axis. (d) (left) View of metal-organic layer of 2. All hydrogen atoms and CF3 moi-
ꢁ
ꢁ
(HeO4 2.813(16)A), O1WeHꢀO2W#4 (HeO2W#4 2.809(13) A),
ꢁ
O2WeHꢀO5#1 (HeO5#1 3.040(3) A), and O1WeHꢀO8#4 (He
ꢁ
O8#4 2.823(13) A), which are further consolidated the layer.
eties of CF3COe2 are omitted for clarity. Selected bond lengths [A]: C1hC2 1.198(9),
ꢁ
Neighboring layers are linked by weak C8eHꢀF9#5 (HeF9#5
Ag1eC1 2.116(11), Ag2eC1 2.142(10), Ag2eC2 3.094(10), Ag3eC1 2.353(11), Ag3eC2
2.948(11), Ag1#1ꢂC2 3.082(9), Ag4#2ꢂC2 2.993(11), Ag1ꢀAg2 2.9047(12), Ag1ꢀAg3
2.8911(12), Ag2ꢀAg3 2.8698(11). Symmetry codes: #1 ꢂx þ 2, ꢂy þ 1, ꢂz þ 1;
#2 ꢂx þ 1, ꢂy þ 2, ꢂz þ 1; #3 x þ 1, y, z; #4 ꢂx þ 2, ꢂy þ 2, ꢂz þ 1. Atom color codes:
Ag purple, C gray, O orange, N blue. (For interpretation of the references to colour in
this figure legend, the reader is referred to the web version of this article.)
ꢁ
2.588(12) A) hydrogen bond to form a three-dimensional su-
pramolecular framework, as illustrated in Fig. 1c.
3.2. [(AgL)(AgCF3CO2)3] (2)
As shown in Fig. 2a, the asymmetric unit of 2 contains four
crystallographically independent Ag(I) ions and three tri-
fluoroacetate ions. Different from 1, the ethynide group (C1hC2) is
Ag8 aggregates are linked by two pairs of trifluoroacetate groups
(O1eO2, O1#4ꢂO2#4, and O5eO6, O5#3ꢂO6#3) via m3-O,O0,O0
coordination modes, to yield an infinite column along the b axis.
Linkage of adjacent columns by two pair of inversion-related tri-
fluoroacetate groups (O3eO4, O3#2ꢂO4#2, O5eO6, and
O5#2ꢂO6#2) produces a two-dimensional layer parallel to the ab
plane (Fig. 2c). Owing to the pyrimidinyl ring appended on both
sides of this silver(I) layer, there is no obvious intermolecular
interaction between layers.
enveloped by a square-pyramidal Ag5 basket m5- , , , ,
h1 h1 h1 h2 h2 co-
ordination mode. The peripheral Ag4 atom is hitched to the Ag5
basket by trifluoroacetate groups in m3-O,O0,O0 and m4-O,O,O0,O0
(O3eO4 and O5eO6) modes, respectively. The argentophilic Age
ꢁ
Ag distances vary from 2.870(11) to 2.905(12) A. Such distances
are clearly indicative of the presence of d10ꢂd10 interactions.
Similar to complex 1, adjacent Ag5 baskets are coalesced by
sharing Ag1 and Ag1#1 to yield an Ag8 aggregate (Fig. 2b). Such