Doubly-linked 1D coordination polymers derived from 2 : 2 metallamacrocyclic Ni(II) complexes with bipodal acylthiourea and exo-biaentate 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 ID 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. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2005.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 ID 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. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2005.ArticleArticl

Self-assembly of 2:2 metallamacrocyclic complexes of Nill and Pdll 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 Nill complex: [Ni(L1-S,O)(pyridine)2]2 and [Ni(L1-S,O)(4- dimethylaminopyridine)2]2.

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Targeting water utilities for the threshold problem without waste discharge

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