Self-assembly of Cu(I) metallomacrocycle and coordination polymers with 2,2′:5′,4″-terpyridine directed by anions and solvents

Abstract

The reaction of [Cu(MeCN)4]X (X = BF4, PF6) with 2,2′:5′,4″-terpyridine (2,2′:5′,4″-terpy) in MeOH/MeCN under Ar/C2H4 afforded 1-D Cu(I) coordination polymers {[Cu(2,2′:5′,4″-terpy)(MeCN)]BF4}n (1) and {{[Cu(2,2′:5′,4″-terpy)(MeCN)]PF6}2·H2O}n (2). In complex 1, the tetrahedral Cu(I) atoms are bridged by 2,2′:5′,4″-terpy in the head-to-tail fashion to form an infinite 1-D zigzag chain structure. In complex 2, there are two independent infinite 1-D zigzag chain structures along the b- and c-axises in the unit cell. The weak intermolecular π⋯π stacking interactions exist between opposite 2,2′:5′,4″-terpy ligands. The PF6– anions are surrounded by four opposite MeCN molecules in two crossed zigzag chains. In contrast, the reaction of [Cu(MeCN)4]PF6 with 2,2′:5′,4″-terpy in Me2CO/MeCN under Ar/C2H4 afforded Cu(I) metallomacrocycle [Cu4(2,2′:5′,4″-terpy)4](PF6)4·5Me2CO (3). Four Cu(I) atoms are bridged by the four 2,2′:5′,4″-terpy in a head-to-tail fashion to afford a rhombic Cu(I) metallomacrocycle. One distorted Me2CO molecule is encapsulated in the central vacant space of [Cu4(2,2′:5′,4″-terpy)4]4+ core and two PF6– anions are sandwiched between the rhombic Cu(I) metallomacrocyclic layers. The reactions of Cu(NO3)2·3H2O and Cu turnings with 2,2′:5′,4″-terpy in MeOH/MeCN under Ar afforded 1-D Cu(I) coordination polymer {[Cu(2,2′:5′,4″-terpy)(MeCN)]NO3}n (4). It has been proved that complex 4 could be induced by the autoreduction of Cu(II) species to Cu(I) species.