Chemistry Reference
In-Depth Information
N
N
N
N
N
N
Pd
NH
2
N
Pd
N
N
Pd
=
N
H
2
N
Pd
N
Pd
N
N
N
Pd
N
= Cu
N
N
N
N
66
N
65
Scheme 24 Metal-template and self-assembly synthesis of Solomon link
O
Zn
2+
+ Cu
2+
1:1
N
NH
2
4
+
4
H
H
N
N
NH
2
O
O
O
67
68
69
N
N
O
O
N
N
N
N
=
N
N
O
O
70
N
N
Scheme 25 One-pot synthesis of Solomon link network
Triply interlocked catenanes provide another interesting topological motif,
where two 3D cage frameworks are threaded firmly. Catenane 71 was spontane-
ously formed by the treatment of two kinds of pyridine components 47 and 72 with
metal ions (Scheme
26
)[
132
]. A similar interlocked network was constructed from
47, long pillars, and Pd(II) metals [
133
]. The interlocked cages establish three
compartments, and a triphenylene guest is accommodated in each compartment to
form seven-layered aromatic stacks. Triply interlocked catenane 73 was also
formed by self-assembly of four tripod-shaped bipyridine ligand 74 and four
metal ions (Scheme
27
)[
134
]. Within each catenane cage, all six-chelated Zn(II)
centers have the same configuration to have a chiral cage network.
Recently, dimeric interpenetrated cage 75 was obtained by reaction of pyridine
ligand 77 with [Pd(CH
3
CN)
4
](BF
4
)
2
(Scheme
28
)[
135
]. This system consists of
eight ligands and four metal ions and encapsulates one BF
4
-
ion between the two
inner Pd metals. Upon addition of a halide ion, this cage includes two ions to form a
