Mo(W)/Cu/S Cluster-Based Supramolecular Arrays Assembled from
Preformed Clusters [Et<sub>4</sub>N]<sub>4</sub>[WS<sub>4</sub>Cu<sub>4</sub>I<sub>6</sub>] and [(<i>n</i>-Bu)<sub>4</sub>N]<sub>2</sub>[MoOS<sub>3</sub>Cu<sub>3</sub>X<sub>3</sub>] (X =
I, SCN) with Flexible Ditopic Ligands
In our working toward the rational design and synthesis of cluster-based suppramolecular architectures, a set of
new [WS<sub>4</sub>Cu<sub>4</sub>]- or [MoOS<sub>3</sub>Cu<sub>3</sub>]-based supramolecular assemblies have been prepared from reactions of preformed
cluster compounds [Et<sub>4</sub>N]<sub>4</sub>[WS<sub>4</sub>Cu<sub>4</sub>I<sub>6</sub>] (<b>1</b>) and [(<i>n</i>-Bu)<sub>4</sub>N]<sub>2</sub>[MoOS<sub>3</sub>Cu<sub>3</sub>X<sub>3</sub>] (<b>2</b>, X = I; <b>3</b>, X = SCN) with flexible ditopic
ligands such as dipyridylsulfide (dps), dipyridyl disulfide (dpds), and their combinations with dicyanamide (dca)
anion and 4,4‘-bipy. The cluster precursor <b>1</b> reacted with dps or dpds and sodium dicyanamide (dca) in MeCN to
produce [WS<sub>4</sub>Cu<sub>4</sub>I<sub>2</sub>(dps)<sub>3</sub>]·2MeCN (<b>4</b>·2MeCN) and [WS<sub>4</sub>Cu<sub>4</sub>(dca)<sub>2</sub>(dpds)<sub>2</sub>]·Et<sub>2</sub>O·2MeCN (<b>5</b>·Et<sub>2</sub>O·2MeCN), respectively.
On the other hand, treatment of <b>2</b> with dpds in DMF/MeCN afforded [MoOS<sub>3</sub>Cu<sub>3</sub>I(dpds)<sub>2</sub>]·0.5DMF·2(MeCN)<sub>0.5</sub>
(<b>6</b>·0.5DMF·2(MeCN)<sub>0.5</sub>) while reaction of <b>3</b> with sodium dicyanamide (dca) and 4,4‘-bipy in DMF/MeCN gave rise
to [MoOS<sub>3</sub>Cu<sub>3</sub>(dca)(4,4‘-bipy)<sub>1.5</sub>]·DMF·MeCN (<b>7</b>·DMF·MeCN). Compounds <b>4</b>·2MeCN, <b>5</b>·Et<sub>2</sub>O·2MeCN, <b>6</b>·0.5DMF·2(MeCN)<sub>0.5</sub>, and<b> 7</b>·DMF·MeCN have been characterized by elemental analysis, IR spectroscopy, and single-crystal
X-ray crystallography. Compound <b>4</b> contains a 2D layer array made of the saddle-shaped [WS<sub>4</sub>Cu<sub>4</sub>] cores interlinked
by three pairs of Cu−dps−Cu bridges. Compound <b>5</b> has another 2D layer structure in which the [WS<sub>4</sub>Cu<sub>4</sub>] cores
are held together by four pairs of Cu−dca−Cu and Cu−dpds−Cu bridges. Compound <b>6</b> displays a 1D spiral chain
structure built of the nido-like [MoOS<sub>3</sub>Cu<sub>3</sub>] cores via two pairs of Cu−dpds−Cu bridges. Compound <b>7</b> consists of
a 2D staircase network in which each [MoOS<sub>3</sub>Cu<sub>3</sub>(4,4‘-bipy)]<sub>2</sub> dimeric unit interconnects with four other equivalent
units by a pair of 4,4‘-bipy ligands and two pairs of dca anions. The [WS<sub>4</sub>Cu<sub>4</sub>] core in <b>4</b> or <b>5</b> and the [MoS<sub>3</sub>Cu<sub>3</sub>]
core in <b>7</b> show a planar 4-connecting node and a seesaw-shaped 4-connecting node, respectively, which are
unprecedented in cluster-based supramolecular compounds. The successful assembly of <b>4</b>−<b>7</b> from the three cluster
precursors <b>1</b><b>−</b><b>3</b> through flexible ditopic ligands provides new routes to the rational design and construction of
complicated cluster-based supramolecular arrays.