Metal‐ligand lability and ligand mobility enables framework transformation via ligand release in a family of crystalline 2D coordination polymers

A family of seven silver(I)-perfluorocarboxylate-quinoxaline coordination polymers, [Ag 4 (O 2 CR F ) 4 (quin) 4 ] 1 - 5 (R F = (CF 2 ) n-1 CF 3 ) 4 , n = 1 to 5); [Ag 4 (O 2 C(CF 2 ) 2 CO 2 ) 2 (quin) 4 ] 6 ; [Ag 4 (O 2 CC 6 F 5 ) 4 (quin) 4 ] 7 (quin = quinoxaline), denoted by composition as 4:4:4 phases , was synthesised from reaction of the corresponding silver(I) perfluorocarboxylate with excess quinoxaline. Compounds 1 - 7 adopt a common 2D layered structure in which 1D silver-perfluorcarboxylate chains are crosslinked by ditopic quinoxaline ligands. Solid-state reaction upon heating, involving loss of one equivalent of quinoxaline, yielding new crystalline 4:4:3 phases [Ag 4 (O 2 C(CF 2 ) n-1 CF 3 ) 4 (quin) 3 ] n ( 8 - 10 , n = 1 to 3), was followed in situ by PXRD and TGA studies. Crystal structures were confirmed by direct syntheses and structure determination. The solid-state reaction converting 4:4:4 to 4:4:3 phase materials involves cleavage and formation of Ag–N and Ag–O bonds to enable the structural rearrangement. One of the 4:4:3 phase coordination polymers ( 10 ) shows the remarkably high dielectric constant in the low electric field frequency range.