Sunlight assisted SCSC dimerization of a 1D coordination polymer impacts the selectivity of Pd(ii) sensing in water

Abstract

A one-dimensional coordination polymer (1D CP) [Cd(4-nvp)₂(5-ssa)]·(4-nvp) (1) [4-nvp = 4-(1-naphthylvinyl)pyridine and 5-ssa = 5-sulfosalicylic acid] undergoes topochemical [2+2] cycloaddition by sunlight irradiation to generate a two-dimensional (2D) CP [Cd(rctt-4-pncb)_0.5(4-nvp)(5-ssa)]·(4-nvp) (1′) [rctt-4-pncb = 1,3-bis(4′-pyridyl)-2,4-bis(naphthyl)cyclobutane] in a single-crystal to single-crystal manner. Interestingly, 1′ can be reverted back to 1 by heating and both the CPs selectively recognize Pd²⁺ in aqueous medium; however, the limit of detection is improved after photodimerization.