title: Self-assembly of dinuclear Pd(ii)/Pt(ii) metallacyclic receptors incorporating N-heterocyclic carbene complexes as corners.
abstract: We report herein the self-assembly of a series of new square and rectangular-shaped dinuclear M2L2metallacycles (M = Pd(ii)/Pt(ii)), receptors self-assembled in water from four different N-monoalkyl-4,4'-bipyridinium derivatives as ligands and square-planar Pd(ii) and Pt(ii) metal centers having the chelating N-heterocyclic carbene 1,1'-di(methyl)-3,3'-methylene-4-diimidazolin-2,2'-diylidene. The concentration-dependent Pd2L2metallacycles were successfully obtained and characterized by means of NMR experiments in aqueous media. Due to the strong trans effect exerted by the carbene ligands, the synthesis of the Pt2L2receptors was achieved as well by self-assembly of the components at room temperature in a few hours, in clear contraposition to the harsh reaction conditions usually required for the labilization of other kinetically inert Pt(ii)-N(pyridine) bonds. X-ray diffraction studies of suitable single crystals of two of the obtained receptors offered additional information on the structure of the obtained supramolecules, whose ability as receptors has been explored by the preparation and study of the corresponding inclusion complexes in water with 1,5-dihydroxynaphthalene as the model substrate.
authors.affiliation: Departamento de Química Fundamental and Centro de Investigacións Científicas Avanzadas (CICA), Facultade de Ciencias, Universidade da Coruña, E-15071 A Coruña, Spain. dvazquezg@udc.es marcos.garcia1@udc.es.
authors.forename: Ismael
authors.initials: I
authors.lastname: Marcos
authors.affiliation: Departamento de Química Fundamental and Centro de Investigacións Científicas Avanzadas (CICA), Facultade de Ciencias, Universidade da Coruña, E-15071 A Coruña, Spain. dvazquezg@udc.es marcos.garcia1@udc.es.
authors.forename: Olaya
authors.initials: O
authors.lastname: Domarco
authors.affiliation: Departamento de Química Fundamental and Centro de Investigacións Científicas Avanzadas (CICA), Facultade de Ciencias, Universidade da Coruña, E-15071 A Coruña, Spain. dvazquezg@udc.es marcos.garcia1@udc.es.
authors.forename: Carlos
authors.initials: C
authors.lastname: Peinador
authors.affiliation: Departamento de Química Fundamental and Centro de Investigacións Científicas Avanzadas (CICA), Facultade de Ciencias, Universidade da Coruña, E-15071 A Coruña, Spain. dvazquezg@udc.es marcos.garcia1@udc.es.
authors.forename: Alberto
authors.initials: A
authors.lastname: Fenández
authors.affiliation: Departamento de Química Fundamental and Centro de Investigacións Científicas Avanzadas (CICA), Facultade de Ciencias, Universidade da Coruña, E-15071 A Coruña, Spain. dvazquezg@udc.es marcos.garcia1@udc.es.
authors.forename: Jesús J
authors.identifier: http://orcid.org/0000-0003-4938-0342
authors.initials: JJ
authors.lastname: Fernández
authors.affiliation: Departamento de Química Fundamental and Centro de Investigacións Científicas Avanzadas (CICA), Facultade de Ciencias, Universidade da Coruña, E-15071 A Coruña, Spain. dvazquezg@udc.es marcos.garcia1@udc.es.
authors.forename: Digna
authors.initials: D
authors.lastname: Vázquez-García
authors.affiliation: Departamento de Química Fundamental and Centro de Investigacións Científicas Avanzadas (CICA), Facultade de Ciencias, Universidade da Coruña, E-15071 A Coruña, Spain. dvazquezg@udc.es marcos.garcia1@udc.es.
authors.forename: Marcos D
authors.identifier: http://orcid.org/0000-0002-3189-740X
authors.initials: MD
authors.lastname: García