Lindqvist‐Type (Aryldiazenido)polyoxomolybdates − Synthesis, and Structural and Spectroscopic Characterization of Compounds of the Type (nBu₄N)₃[Mo₆O₁₈(N₂Ar)]

Abstract

A series of aryldiazenido compounds of the type (nBu 4 N) 3 -[Mo 6 O 18 (N 2 Ar)] have been prepared by treatment of (nBu 4 N) 4 - [Mo 8 O 26 ] with the appropriate arylhydrazines in acetonitrile or in methanol. All these compounds are isostructural. Two members of the series, the o-nitro and the p-carboxy derivatives, have been characterized by single-crystal X-ray diffraction. The aryl ring in the first anion lies in a mirror plane of the polyoxometalate, while in the second one it is tilted, allowing hydrogen bonding between the carboxylic acid function and a neighbouring anion. The aryldiazenido ligands exhibit the characteristic features of the singly bent

Synthesis and Spectroscopic Characterization of Organophosphono Derivatives of Lindqvist Niobotungstates – X‐ray Crystal Structures of (nBu4N)3[NbW10O38(RP)2] (R = nBu, Hep and Ph)

“…The lacunary {W 5 O 18 } moieties present trans bondlength alternation for the WO b bonds ( Figure 6a, Table 3), a feature which was already reported in various derivatized Lindqvist anions; [15,19] the difference, ∆, between average long and short bonds within the Nb1-W4-W1-W2-P1 oxo ring is 0.17 Å. No such trans bond-length alternation is observed in the equatorial ring, W2-W3-W4-W5 ( Figure 6b); on the contrary, the W-O bond lengths along this ring are quite similar with a difference between minimum and maximum values of 0.05 Å.…”

Electroactive Benzothiazole Hydrazones and Their [Mo6O19]2− Derivatives: Promising Building Blocks for Conducting Molecular Materials

“…(O t and O b mark out terminal and bridging oxo ligands, respectively). Such splittings are commonly observed in monofunctionalised hexamolybdates, for example, diazenido [52] and imido [54] derivatives.…”

“…L] nÀ in which L is a nitrogenous ligand. Following the pioneering investigations by Zubieta and co-workers, [46] this family of polyanions has been extended by Errington, Maatta, Proust, Peng and Wei groups [32] and now includes nitrosyl, [47][48][49] hydrazido, [50] diazenido [46,[51][52] nitrido [50] and imido [53][54][55][56][57][58] derivatives. One diazoalkane derivative has been also reported by Maatta and coworkers.…”

A Quantum Mechanical Study of the Second‐Order Nonlinear Optical Properties of Aryldiazenido‐Substituted Hexamolybdates: A Surprising Charge Transfer

“…[39] Their structures are sketched in Figure 1 and the optimized bond lengths are given in Table 1. The agreement between experimental and calculated metrical parameters of system 1 gives us confidence that the present study is consequential for this research work.…”

“…[33,34] With regard to the functionalization of POMs, interest in the replacement of terminal oxido ligands by other multiply bonded ligands such as nitrosyl, [35] imido, [36,37] and nitride [38] ligands may provide better understanding about aryldiazenido hexamolybdates. However, Lindqvist-type aryldiazenido hexamolybdates have been synthesized by Bustos et al [39] In the present theoretical research work, for the first time we performed DFT calculations on aryldiazenido hexamolybdates to predict their first hyperpolarizabilities (secondorder polarizabilities). The effect of an electron donor (-NH 2 ) in the ortho, meta, para, and ortho/para positions on the aromatic ring of the aryldiazenido ligand with respect to the first hyperpolarizability was investigated.…”