One-Pot versus Sequential Reactions in the Self-Assembly of Gigantic Nanoscale Polyoxotungstates

Abstract

By using a new type of lacunary tungstoselenite {Se(2)W(29)O(103)} (1), which contains a "defect" pentagonal {W(W)(4)} unit, we explored the assembly of clusters using this building block and demonstrate how this unit can give rise to gigantic nanomolecular species, using both a "one-pot" and "stepwise" synthetic assembly approach. Specifically, exploration of the one-pot synthetic parameter space lead to the discovery of {Co(2.5)(W(3.5)O(14))(SeW(9)O(33))(Se(2)W(30)O(107))} (2), {CoWO(H(2)O)(3)(Se(2)W(26)O(85))(Se(3)W(30)O(107))(2)} (3), and {Ni(2)W(2)O(2)Cl(H(2)O)(3)(Se(2)W(29)O(103)) (Se(3)W(30)O(107))(2)} (4), effectively demonstrating the potential of the {Se(2)W(29)} based building blocks, which was further extended by the isolation of a range of 3d transition metal doped tetramer family derivatives: {M(2)W(n)O(m)(H(2)O)(m)(Se(2)W(29)O(102))(4)} (M = Mn, Co, Ni or Zn, n = 2, m = 4; M = Cu, n = 3, m = 5) (5-9). To contrast the 'one-pot' approach, an optimized stepwise self-assembly investigation utilizing 1 as a precursor was performed showing that the high nuclearity clusters can condense in a more controllable way allowing the tetrameric clusters (5-8) to be synthesized with higher yield, but it was also shown that 1 can be used to construct a gigantic {W(174)} hexameric-cluster {Cu(9)Cl(3)(H(2)O)(18)(Se(2)W(29)O(102))(6)} (10). Further, 1 can also dimerize to {(Se(2)W(30)O(105))(2)} (11) by addition of extra tungstate under similar conditions. All the clusters were characterized by single-crystal X-ray crystallography, chemical analysis, infrared spectroscopy, thermogravimetric analysis, and electrospray ionization mass spectrometry, which remarkably showed that all the clusters, even the largest cluster, 10 (∼50 kD), could be observed as the intact cluster demonstrating the extraordinary potential of this approach to construct robust gigantic nanoscale polyoxotungstates.

Antibacterial Activity of Polyoxometalates Against Moraxella catarrhalis

“…The Preyssler POT (Figure 1A) (NH 4 ) 14 [NaP 5 W 30 O 110 ]·30H 2 O (Jeannin et al, 2007); heteropolymetalates with Dawson structure (Figure 1B): K 6 [P 2 W 18 O 62 ]·14H 2 O (Contant et al, 2007), (NH 4 ) 6 [P 2 Mo 18 O 62 ]·12H 2 O (Briand et al, 2002), [(C 16 H 36 ) 4 N] 4 [P 4 Mo 18 O 61 ] (Kortz and Pope, 1994), (CH 6 N 3 ) 6 [As 2 Mo 18 O 62 ]·9H 2 O (Ichida and Sasaki, 1983), [(CH 3 ) 4 N] 4 [S 2 Mo 18 O 62 ] (Hori and Himeno, 1987), Na 12 [P 2 W 15 O 56 ]·25H 2 O (Contant et al, 2007), [N(CH 3 ) 4 ] 6 [H 3 P 2 W 15 V 3 O 62 ]·6H 2 O (Finke et al, 1986), K 6 [As 2 W 18 O 62 ]·14H 2 O (Bi et al, 2000), Na 7 [AsW 18 O 60 ]·16H 2 O (Jeannin and Martin-Frere, 1979); heteropolymetalates with Keggin-based structures (Figures 1C-E): Na 3 [PW 12 O 40 ]·12H 2 O (Phillips, 1950), (NH 4 ) 5 [H 2 PCoW 11 O 40 ] (Komura et al, 1976), K 6 H 2 [CoTiW 11 O 40 ]·13H 2 O (Kraus et al, 2005), K 8 [SiW 10 O 36 ]·10H 2 O (Téazéa et al, 2007), Na 9 [SbW 9 O 33 ]·19.5H 2 O (Tourné et al, 1973); Na 9 [AsW 9 O 33 ]·19.5H 2 O (Tourné et al, 1973), K 14 [As 2 W 19 O 67 (H 2 O)] (Kortz et al, 2001); K 9 (C 2 H 8 N) 5 [H 10 Se 2 W 29 O 103 ]·30H 2 O (Gao et al, 2013); isopolymetalates (Figures 1F,G): Na 10 [W 12 O 40 (OH) 2 ]·20H 2 O (Evans and Rollins, 1976), Na 12 [H 4 W 22 O 74 ]·31H 2 O (Miras et al, 2008), [(C 4 H 9 ) 4 N] 2 [Mo 6 O 19 ] (Klemperer, 2007), [(C 4 H 9 ) 4 N] 4 [α-Mo 8 O 26 ] (Klemperer, 2007), K 4 Na 2 [V 10 O 28 ]·10H 2 O (Lee and Joo, 2003), K 4 [V 4 O 8 (L-tart) 2 ]·8H 2 O, tart = C 4 H 2 ${\text{O}}_6^{4-}$ (Schwendt et al, 2007), K 4 [V 4 O 8 (D-tart) 2 ]·8H 2 O, tart = C 4 H 2 ${\text{O}}_6^{4-}$ (Schwendt et al, 2007); heteropolymetalates with Anderson structure (Figure 1I) : Na 6 [TeW 6 O 24 ]·22H 2 O (Schmidt et al, 1986), Na 4 [Ni(OH) 6 W 6 O 18 ]·16H 2 O (Rozantsev et al, 2009), Na 4 [Ni(OH) 6 Mo 6 O 18 ]·16H 2 O (Gumerova et al, 2015), Na 2 [N(CH 3 ) 4 ] 2 [Ni(OH) 3 W 6 O 18 (OCH 2 ) 3 CCH 2 OH]·9H 2 O (Gumerova et al, 2016) were synthesized according to procedures published elsewhere. Table 1 lists the POMs tested in this study together with notation of their abbreviation.…”

Polyoxoanions assembled by the condensation of vanadate, tungstate and selenite: solution studies and crystal structures of the mixed metal derivatives (NMe4)2Na2[WVI4VV2O19]·8H2O and (NMe4)4.83[(SeIV WVI4.57VV4.43O33)2(WVI(O)(H2O))(VVO)2.6]·10.57H2O

“…28 Recently the Cronin group reported characterization of a large selenite polytungstate family, of which the individual members are highly labile and coexist at very close pH values. 29 Addition of the vanadates to the WO 4 2-/ SeO 3 system could be expected to introduce more complexity. Partial substitution of vanadium for tungsten may affect the relative stability of various building blocks present in the virtual library of the selenopolymetalates.…”

Time‐Resolved Assembly of Cluster‐in‐Cluster {Ag12}‐in‐{W76} Polyoxometalates under Supramolecular Control

“…[15] Indeed, an alternative interpretation of the structure of 4 is that it is simply an extended analogue of the previously reported {Se 2 W 29 } cluster (Figure 3 b), in which the "base" of 4 is an analogous {Te 2 W 29 } unit that has further condensed with an additional {W 3 } unit, itself linked in turn by two {W 1 } linkers to a third {TeW 9 } cluster. It also contains three {TeW 9 } units arranged around a central {W 16 } tungstate core, which contains an interesting monolacunary {W(W 4 )} pentagonal unit that has recently been reported by our group.…”