Feng-Bo Xu

The first synthesis of a calix[4](diseleno)crown ether as a sensor for ion-selective electrodes

Two calix[4](diseleno)crown ethers 3 and 4 were synthesized by reaction of the disodium salt of 1,3-propanediselanol with the preorganized 1,3-dibromoethoxylcalix[4]arenes 1 and 2 . Compound 3 forms an interesting infinite sheet aggregate via self-inclusion and intermolecular Se⋯Se interactions in the solid state. Preliminary evaluation of 3 and 4 as ionophores for ion-selective electrodes (ISEs) is reported.

Silver(I) N-heterocyclic carbene-bridged calix(4)arene analogues as efficient (60)fullerene receptors{

Two silver(I) N-heterocyclic carbene-bridged calix[4]arene analogues 4 and 5 were synthesized by a fragment-coupling approach; the preliminary inclusion properties of 5 with [60]fullerene shows that it is a novel efficient [60]fullerene fluorescent sensor.

Dinuclear Ag(I) metallamacrocycles of bis-N-heterocyclic carbenes bridged by calixarene fragments: synthesis, structure and chemosensing behavior

Dinuclear Ag(I) metallamacrocycles containing bis-N-heterocyclic carbene units and calixarene fragments [{1,1′-R2-3,3′-CH2{(p-R1-C6H2OMe)CH2}m-bisimidazol-2-ylidene}2-Ag2](PF6)2 (6a–f), (6a: m = 1, R1 = Me, R2 = Me; 6b: m = 1, R1 = t-Bu, R2 = Me; 6c: m = 1, R1 = Me, R2 = naphthylmethyl; 6d: m = 1, R1 = Me, R2 = anthrylmethyl; 6e: m = 2, R1 = Me, R2 = anthrylmethyl; 6f: m = 3, R1 = t-Bu, R2 = anthrylmethyl) were synthesized by reacting silver oxide with the corresponding bis-imidazolium salts (5a–f). Single crystal structural analyses reveal that metallamacrocycles of diverse sizes consisting of two NHC–Ag(I)–NHC units and two calixarene fragments are found in the structures of these dinuclear complexes. These complexes show different configurations with the change of the upper-rims (R1) of the calixarene fragments or N-substituents (R2) of the NHC rings. The two bis-NHC ligands in the complexes generally adopt trans-conformations except for the pair in 6b. Complexes 6a and 6c–d, in which R1 are methyl groups, show rectangular cavities in their structures. Complex 6b, in which R1 are tert-butyl groups of great steric hindrance, adopts cone conformation analogous to that of the calixarene. Interestingly, cation–π interactions are present between Ag(I) and the π–electron rich arene ring of R2 in the structures of complexes 6c–f. Intermolecular C–H⋯F hydrogen bonds exist in the crystal packing of all these complexes. Moreover, intermolecular Ag⋯Ag interactions are found in complex 6a and intermolecular π–π interactions are observed in complexes 6c–f. These intermolecular interactions lead to the formation of 2D supramolecular layers in complex 6c and 3D supramolecular networks in complexes 6a–b and 6d–f, respectively. The fluorescent chemosensing behaviors of these metallamacrocycles were explored for some neutral molecules. The results showed that 6d can behave as an efficient fluorescent chemosensor for p-benzoquinone and 6e–f exhibit fluorescent quenching behaviors for C60 or C70 fullerenes.

Synthesis of a tweezer-like bis(arylthiaalkoxy)calix[4]arene as a cation sensor for ion-selective electrodes: an investigation of the influence of neighboring halogen atoms on cation selectivity

Two novel tweezer-like 25,27-dihydroxy-26,28-bis(phenylthiaethoxy)calix[4]arenes 6 and 7 were synthesized by the reaction of 25,27-dihydroxy-26,28-bis(bromoethoxy)calix[4]arenes 3 and 4 for the evaluation of their ion-selectivity in ion-selective electrodes (ISEs). X-ray structural analysis indicated that calix[4]arene 7 is in an interesting infinite linear aggregate via self-inclusion. For investigation of the influences of substitutes on the behavior of the ISEs, the halogen substituted aryl analogues of 25,27-dihydroxy-26,28-bis(arylthiaethoxy)calix[4]arenes 8-12 were also synthesized and their ISE performances were evaluated under the same conditions. ISEs based on 6-12 as neutral ionophores were prepared, and their selectivity coefficients for Ag+ (log KAg,M(pot)) were investigated against other alkali metal, alkaline-earth metal, lead, ammonium ions and some transition metal ions using the fixed interference method (FIM). These ISEs showed excellent Ag+ selectivity over most of the interfering cations examined, except for Hg2+ having relative smaller interference (log KAg,Hg(pot) < or = 2.1). The 19F NMR spectra of 9 and 9.AgClO4 were recorded for investigation the fluorine environments in the complex. The 19F NMR spectra strongly suggested that the fluorine atoms on ionophore 9 participated in ligation with silver cation.

Novel bis(phenylselenoalkoxy)calix[4]arene molecular tweezer receptors as sensors for ion-selective electrodes

Four tweezer-like 25,27-dihydroxy-26,28-bis(phenylselenoalkoxy)-5,11,17,23-tetra-tert-butylcalix[4]arenes 5–8 were synthesized for the evaluation of their ion-selectivity in ion-selective electrodes (ISEs). For investigation of the influences of the coordinate atoms on the ion-selectivity, 25,27-dihydroxy-26,28-bis(alkylthiaalkoxy)-5,11,17,23-tetra-tert-butylcalix[4]arenes 9–11 were also prepared and characterized. On the other hand, 1,3-bis(phenylseleno)propane 12 was synthesized for comparison of the influences of coordinate patterns of different ionophores on the ion-selectivity of ISEs. ISEs based on 5–12 as neutral ionophores were prepared, and their selectivity coefficients for Ag+ (log KpotAg,M) were investigated against alkali metal, alkaline-earth metal, lead, and ammonium ions and some transition metal ions using the fixed interference method (FIM). These ISEs showed excellent Ag+ selectivity over most of the interfering cations examined, except for Hg2+, which had relatively smaller interference (log KpotAg,Hg ≤ −1.6).

Coordination chemistry of organometallic polydentate ligand Reactive chemistry of the tridentate ligand trans‐Fe(Ph2PQu‐P)2‐(CO)3 [PhzPQu=2‐diphenyl‐phosphino‐4‐methylquinoline] and molecular structure of [Fe(CO)3(μ‐Ph2PQu)2HgI]+ [HgI3]

Reaction of a new type of bidentate ligand PhPQu [ PhPQu = 2-diphenylphosphino-4-methylquinoline] with Fe(CO)5 in bu-tanol gave trans-Fe(PhPQu-P)(CO)3 (1).Compound 1,which can act as a neutral tridentate organometallic ligand,was reacted with I B,II B metal compounds and a rhodium complex to give six binuclear complexes with Fe-M bonds,Fe(CO)3(u-Ph2PQu)MXn(2-7) [M=Zn(Ⅰ),Cd(Ⅱ),Hg(Ⅱ),Cu(Ⅰ),Ag(Ⅰ),Rh(Ⅰ)],and an ion-pair complex [Fe(CO)3(n-Ph2PQu)2HgI][HgI3]- (8).The structure of 8 was determined by X-ray crystallography.Complex 8 crystallizes in the space group P-1 with a=1.0758(3),b= 1.6210(4),c = 1.7155(4) nm; a = 75.60(2)β=71.81(2),Y = 81.78(2) and Z = 2 and its structure was refined to give agreement factors of R =0.050 and Rw = 0.057.The Fe-Hg bond distance is 0.2536 nm.

CCDC 857745: Experimental Crystal Structure Determination

Related Article: Cai-Xia Lin, Xiao-Fei Kong, Feng-Bo Xu, Zheng-Zhi Zhang and Yao-Feng Yuan|2013|Z.Anorg.Allg.Chem.|639|881|doi:10.1002/zaac.201300067

Tetra­aqua­bis[1,1′-(4-methoxy­naph­thalene-1,3-diyldimethyl­ene)pyridinium-3-carboxyl­ate-κO]cobalt(II) bis­(perchlorate) hexa­hydrate

In the molecule of the centrosymmetric title compound, [Co(C25H20N2O5)2(H2O)4](ClO4)2·6H2O, the Co atom is octahedrally coordinated by four water molecules lying in the equatorial plane and two monodentate carboxylate groups from two dicarboxylate ligands. The crystal structure involves O—H⋯O and O—H⋯Cl hydrogen bonds..

Dichloro­{N-(diphenyl­phosphino)-N-[(diphenyl­phosphor­yl)meth­yl]pyridin-2-amine-κ2N,N′}platinum(II)

The title compound, [PtCl2(C30H26N2OP2)], is a mononuclear PtII complex. The Pt atom is coordinated by one pyridine N atom, one P atom and two Cl atoms, which form a distorted square plane around the PtII atom.

{2-[N-Benzyl-N-(diphenyl­phosphinometh­yl)amino]pyridine}tricarbonyl­chloro­rhenium(I)

Over the past few decades, tertiary phosphines have attracted considerable interest, especially as important ligands in coordination chemistry (Zhang & Cheng, 1996). To obtain cluster compounds, rhenium carbonyl complexes are used as starting materials along with hydrogen and hydrides (Saillant et al., 1970; Bau et al., 1967). Previously, we have reported the crystal structures of some heterobimetallic Pt–M (M = Cu, Ag) macrocyclic complexes with a large-bite P,N-bidentate ligand, including 2-[N-benzyl-N-(diphenylphosphinomethyl)amino]pyridine (Li et al., 2003). Now we report here the structure of the title compound, (I), a new Re complex with the abovecited ligand.