Improving the Robustness of Organic Semiconductors through Hydrogen Bonding

Molecular organization plays an essential role in organic semiconductors since it determines the extent of intermolecular interactions that govern the charge transport present in all electronic applications. The benefits of hydrogen bond-directed self-assembly on charge transport properties are demonstrated by comparing two analogous pyrrole-based, fused heptacyclic molecules. The rationally designed synthesis of these materials allows for inducing or preventing hydrogen bonding. Strategically located hydrogen bond donor and acceptor sites control the solid-state arrangement, favoring the supramolecular expansion of the π-conjugated surface and the subsequent π-stacking as proved by X-ray d…

Solid state conformational and theoretical study of complexes containing the (CxN)Pd moiety (CxN = 2-(phenylazo)phenyl-C,N and its derivatives)

Palladium complexes having the 2-(phenylazo)phenyl-C,N ligand exhibit a planar chelating ring with NN and N–C distances longer and shorter respectively than those found in trans-azobenzene. The ligand is not planar upon complexation, the mean angle between the phenyl ring and the chelating one found in the Cambridge Structural Database being of 45.6°. We have quantified and characterised the kind of distortion from planar coordination around metallic centers. The method employed makes use of two improper torsion angles, tetrahedral distortion being most frequently found in phenylazophenyl palladium complexes. Crystal structures of three succinimidate complexes having the title moiety are re…

Reactivity of the di-μ-hydroxo-complexes [{Pd(NN)}2(μ-OH)2][ClO4]2 (NN=bis(pyrazol-1-yl)alkanes) towards protic electrophiles. Hydration of coordinated nitriles at a palladium(II) site

Abstract The hydroxo-complexes [{Pd(μ-OH)(NN)}2][ClO4]2 (NN=bpzm:bis(pyrazol-1-yl) methane: a-compounds, bpzm*:bis(3,5-dimethylpyrazol-1-yl)methane; b-compounds) react with a wide variety of weak protic electrophiles H(LL) in a 1:2 molar ratio to give the mononuclear cationic palladium(II) derivatives of general formula [Pd(LL)(NN)][ClO4] [LL=2-pyridine-methoxo (OCH2-py) (1a,b); picolinate (pic) (2a,b); 8-hydroxiquinolinate (oxin) (3a,b)] or the dinuclear complexes [{Pd(NN)}2(μ-ox)][ClO4]2 [ox=oxalate: (4a,b)] and [{Pd(μ-LL)(NN)}2][ClO4]2 [LL=pyrazolate (pz) (5a,b); p-thiocresolate (SC6H4Me-p) (6a,b); triazolate (tz) (7b); thiophenolate (SPh) (8b)] when reacting with oxalic acid, azole…

Networks based on hydrogen-bonds containing phosphorus anions and tris(3,5-dimethylpyrazolyl)borate nickel(II) moieties

Abstract Five structural kinds of nickel hydrogen-bonded networks containing hydrotris(3,5-dimethylpyrazolyl)borate ligands (Tp∗) have been elucidated by X-ray diffraction, [Tp∗Ni(OH2)3][(p-NO2C6H4O)2PO2] (4), [Tp∗Ni(OH2)3][Me2PO2]·Me2P(O)OH (5), [Tp∗Ni(OH2)3][(nBuO)2PO2]·0.5H2O (6), [(Hpz)Tp∗Ni(OH2)2][(Ph)PO2OH] (7) and [Tp∗Ni(OH2)2(Me2PO2)] (8). The most relevant supramolecular feature of complexes 4–8 is all of them form coordination networks based on hydrogen bonds between water molecules and phosphate, phosphonate or phosphinate anions. These hydrogen bonds are formed within the monomer units in addition to connect monomers along the chains. Their behaviors in solution were investigate…

New Di- and Trinuclear Complexes with Pyrazolato Bridges. Crystal Structures of [{(C6F5)2Pd(μ-pz)(μ-Cl)}2Pd]2– and [(C6F5)2Pd(μ-pz)2Pd(η3-C4H7)] (pz = pyrazolate)

Reactivity Towards Acidic Protic Ligands of Cyclopalladated Di‐μ‐hydroxo Complexes

The dinuclear hydroxo complexes [{Pd(μ-OH)(C∧N)}2] [C∧N = 2-(2-pyridyl)phenyl (Phpy) (I), 7,8-benzoquinolyl (Bzq) (II) and 2-(2-oxazolinyl)phenyl (Phox) (III)] react in a 1:2 molar ratio with a wide variety of protic electrophiles H(L∧L) bearing different sets of donor atoms (L∧L = O∧O or O∧N) to give the mononuclear neutral palladium(II) derivatives with the general formula [Pd(L∧L)(C∧N)] [O∧O = salicylaldehydate (sal) (1), acetylacetonate (acac) (2) and benzoylacetonate (bzac) (3); O∧N = N-phenylsalicylaldiminate (N-Phsal) (4), N-p-chlorophenylsalicylaldiminate (N-pClPhsal) (5), 2-pyrrolecarbaldeydate (2-pcal) (6), 8-hydroxyquinolinate (oxin) (7)]. Structural characterisation of complexes…

Hydrogen Bonding and Anion Binding in Structures of Tris(pyrazolyl)boratenickel(II) and Phosphate Esters

This paper presents the syntheses, crystal structures and spectroscopic properties of a series of nickel(II) complexes containing hydrotris(3,5-dimethylpyrazolyl)borate and phosphate esters: [Tp*Ni(Hpz*)2(L)][(RO)2PO2] [R = Et, Bu; L = H2O (1), (BuO)2P(O)OH (2)] and [Tp*Ni(Hpz*)(H2O)2][(EtO)2PO2] (5) {Tp* = hydrotris(3,5-dimethylpyrazolyl)borate, Hpz* = 3,5-dimethylpyrazole}. The complexes [Ni(Tp*)2] (3) and [(Tp*Ni)2(μ-pz*)(μ-OH)](4) were also prepared and fully characterized. X-ray crystallographic studies of 1 and 2 reveal that the pyrazole moieties are hydrogen bonded to the guest phosphate ester anion. In complex 5, the phosphate anion is hydrogen-bonded by two O–H groups of the water …

Synthesis and characterization of cyclometallated palladium(II) complexes with 2-(diphenylphosphino)benzaldehyde

New palladium(II) complexes containing 2-(diphenylphosphino)benzaldehyde a (Ph2P(o-C6H4CHO), displaying different coordination modes, have been synthesized in moderate to good yields (62–91%). The cyclometallated palladium(II) complexes [Pd(C^N)(Ph2 P(o-C6H4CHO)(Cl)] (1–4) in which a is P-monodentate have been prepared by reacting it with selected cyclometallated precursors containing bridging chlorides [Pd(C^N)(μ-Cl)]2 [C^N=2-phenylpyridine (Phpy), 7,8-benzoquinoline (Bzq), azobenzene (Phazo), and 2-phenyloxazoline (Phox), respectively]. A rigid P,O-chelating behavior of a, confirmed by the crystal structure determination of [Pd(Phox)(Ph2 P (o-C6H4CHO)][CF3SO3] (8), is observed in complexe…

CCDC 2036011: Experimental Crystal Structure Determination

Related Article: Paula Gómez, Stamatis Georgakopoulos, Miriam Más-Montoya, Jesús Cerdá, José Pérez, Enrique Ortí, Juan Aragó, David Curiel|2021|ACS Applied Materials and Interfaces|13|8620|doi:10.1021/acsami.0c18928