Susan A. Bourne

Self‐Assembly of Nanometer‐Scale Secondary Building Units into an Undulating Two‐Dimensional Network with Two Types of Hydrophobic Cavity

A series of bowls separated by hour-glass-shaped channels characterizes the structure of the undulating two-dimensional coordination polymer that is prepared from a nanoscale secondary building unit (nSBU), which is formed by four square metal(II)carboxylate SBUs that have 1,3-benzenedicarboxylate units as 120° spacers.

Hydrophilic platinum complexes of N-2-hydroxyethyl- and N,N-di(2-hydroxyethyl)-N′-benzoylthiourea ligands. Crystal and molecular structure of N,N-di(2-hydroxyethyl)-N′-benzoythiourea

Abstract The crystal and molecular structure of hydrophilic N,N-di(2-hydroxyethyl)-N′-benzoylthiourea (H3L4) has been determined. This ligand coordinates to Pt(II), Pd(II) and Ni(II) in a bidentate manner yielding essentially neutral complexes of the type cis-[Pt(H2L4)2]. By contrast, N-(2-hydroexyethyl)-N′-benzoylthiourea (H3L5) behaves like a monodentate thiourea ligand and reacts with Pt(II) to yield a mixture of cis and trans complexes of [Pt(H3L5)2Cl2]. The ( + )FAB mass spectrum of the latter complexes is also discussed.

Self-assembly of 2:2 metallomacrocyclic complexes of NiII and PdII with 3,3,3′,3′-tetraalkyl-1,1′-isophthaloylbis(thioureas). Crystal and molecular structures of cis-[Pd(L2-S,O)]2 and the adducts of the corresponding NiII complexes: [Ni(L1-S,O)(pyridine)2]2 and [Ni(L1-S,O)(4-dimethylaminopyridine)2]2

Abstract The bipodal ligands 3,3,3′,3′-tetraethyl-1,1′-isophthaloylbis(thiourea), H 2 L 1 , and 3,3,3′,3′-tetra( n -butyl)-1,1′-isophthaloylbis(thiourea), H 2 L 2 , react with Ni(II) and Pd(II) to form exclusively 2:2 metallomacrocyclic cis -[Pd(L 2 - S , O )] 2 and cis -[Ni(L 1 - S , O )] 2 complexes in high yields. Purple-brown cis -[Ni(L 1 - S , O )] 2 readily form green adducts cis- [Ni(L 1 - S , O )(X) 2 ] 2 (X is pyridine or 4-dimethylaminopyridine), in which two X molecules are axially bound to each Ni(II) atom. Thermogravimetric analysis of these adducts shows that cis- [Ni(L 1 - S , O )(X) 2 ] 2 revert back to the planar cis -[Ni(L 1 - S , O )] 2 complexes on heating. The crystal structures of 3,3,3′,3′-tetraethyl-1,1′-isophthaloylbis(thiourea), cis -[Pd(L 2 - S , O )] 2 , cis- [Ni(L 1 - S , O )(pyridine) 2 ] 2 and cis- [Ni(L 1 - S , O )(4-dimethylamino-pyridine) 2 ] 2 are reported.

1-D coordination polymers containing benzenedicarboxylate

Abstract The preparation and crystal structures of [Cu(1,3-bdc)(py)3].1 1 2 H2O (1), [Cu(1,3-bdc)(py)3].H2O.CH3OH (2), [Co(1,3-bdc)(py)3(H2O)] (3), [Co(1,3-bdc)(py)3(CH3OH)].H2O (4), [Cu(1,3-bdc)(py)2] (5), [Co(1,3-bdc)(CH3OH)4] (6) and [Ni(1,3-bdc)(CH3OH)4] (7) are described (1,3-bdc=1,3-benzenedicarboxylic acid; py=pyridine). 1–4 form straight-chain 1-D coordination polymers with interdigitated pyridyl ligands that are engaged in C-H···π hydrogen bonds. 6 and 7 form similar 1-D polymeric chains, but the smaller methanol ligands allow the bdc groups to stack to form π···π interactions. 5 forms a rectangular 2-D grid structure with insufficient space for guest inclusion.

Metallamacrocyclic complexes of Ni(II) with 3,3,3′,3′-tetraalkyl-1,1′-aroylbis(thioureas): crystal and molecular structures of a 2 : 2 metallamacrocycle and a pyridine adduct of the analogous 3 : 3 complex

The crystal and molecular structure of a square planar 2 : 2 metallamacrocyclic Ni(II) complex of 3,3,3′,3′-tetraethyl-1,1′-isophthaloylbis(thiourea) is reported together with that of the octahedral Ni(II) pyridine adduct of the corresponding 3 : 3 metallamacrocycle synthesised from 3,3,3′,3′-tetraethyl-1,1′-terephthaloylbis(thiourea). The former complex is a nearly planar molecule which packs in a manner dictated by strong π–π interactions. The latter is found to possess an unusually large unit cell containing two adduct molecules, with significantly dissimilar conformations, and five pyridine guests. Most of the guest molecules are located in close proximity to the adduct molecules, in contrast with the mode of host–guest interactions observed for pyridine adducts of analogous 2 : 2 metallamacrocycles.

Dalton communications. Intramolecular hydrogen-bond controlled unidentate co-ordination of potentially chelating N-acyl-N′-alkylthioureas: crystal structure of cis-bis(N-benzoyl-N′-propylthiourea) dichloroplatinum(II)

The crystal and molecular structure of cis-bis(N-benzoyl-N′-propylthiourea) dichloroplatinum(II) shows that two N-benzoyl-N′-propylthiourea molecules co-ordinate to PtII through the sulfur atom only, the acyl oxygen atom being effectively blocked from co-ordination by an intramolecular hydrogen bond, in contrast to the chelating N-benzoyl-N′,N′-dialkylthiourea analogues.

Phenylamines as building blocks to layered inorganic–organic structures

Five inorganic–organic layered composites have been prepared and characterised. Copper(II) chloride and lead(II) chloride compounds with 1,4-phenylenediamine and benzidine have a 1∶1 inorganic∶organic layer structure. The copper(II) chloride structure with p-biphenylamine is a 1∶2 inorganic∶organic layer structure; this compound undergoes an order–disorder transition at ca. 200 K. Crystallisation of benzidine in the presence of lead (II) chloride or cobalt(II) chloride at elevated temperature produced the chloride salt of benzidine.

Chiral carboxylic acids and their effects on melting-point behaviour in co-crystals with isonicotinamide

The crystal structures of co-crystals of two systems of chiral carboxylic acids, optically active and racemic 2-phenylpropionic acid and 2-phenylbutyric acid, with isonicotinamide are reported to investigate the effects of the chirality of the chiral carboxylic acids on the melting point of the co-crystal complexes. It was found that the racemic co-crystal has a higher melting point than the optically active co-crystal, which correlates with the denser packing arrangement inherent in centrosymmetric space groups.

Doubly-linked 1D coordination polymers derived from 2 ∶ 2 metallamacrocyclic Ni(II) complexes with bipodal acylthiourea and exo-bidentate N-donor bridging ligands: toward potentially selective chemical sensors?

The square planar 2 ∶ 2 metallamacrocyclic Ni(II) complex of 3,3,3′,3′-tetraethyl-1,1′-isophthaloylbis(thiourea) readily forms coordination polymers by axial coordination of various exo-bidentate N-donor linkers: pyrazine, 4,4′-bipyridine, 1,2-bis(4-pyridyl)ethane and 1,2-di(4-pyridyl)ethylene. Steric constraints, together with coordination limited to the axial directions, result in the self-assembly of double-linked 1D ladder structures. One compound in particular, with the bridging ligand 1,2-di(4-pyridyl)ethylene, is found to exist as a quasi-polymer, realising only one-third of its potential linkages. On exposure to various solvents, this compound appears to undergo complete polymerisation, both rapidly and fully reversibly with an associated colour change, making it a potential chemical sensor.

Protonation mediated interchange between mono- and bidentate coordination of N-benzoyl-N′,N′-dialkylthioureas: crystal structure of trans-bis(N-benzoyl-N′,N′-di(n-butyl)thiourea-S)-diiodoplatinum(II)

Abstract Treatment of a chloroform/ethanol solution of cis -bis( N -benzoyl- N ′, N ′-di( n -butyl)thioureato- S , O )platinum(II) with an excess HI quantitatively converts the former cis complex into trans -bis( N -benzoyl- N ′, N ′-di(n-butyl)thioureau- S )diiodoplatinum(II). The crystal structure of the latter complex is reported and represents the first example of a Pt(II) complex in which the amidic O -donor atom of the usually bidentate N -benzoyl- N ′, N ′-di(butyl)thiourea ligand (HL) is pendant. In chloroform- d 3 solution, the trans -Pt(HL- S ) 2 I 2 ] complex rapidly isomerizes to give a 1:4 mixture of the cis and trans isomers, as can be seen in the 1 H and 195 Pt NMR spectra.