Polytorsional-amide/carboxylates-directed Cd(ii) coordination polymers exhibiting multi-functional sensing behaviors.

By rational assembly of polytorsional-amide [ N , N '-bis(4-methylenepyridin-4-yl)-1,4-naphthalene dicarboxamide (L)] and polytorsional-carboxylates [H 2 ADI = adipic acid, H 2 PIM = pimelic acid, H 2 SUB = suberic acid], three new Cd-based coordination polymers (CPs) C 30 H 30 CdN 4 O 7 (1), C 31 H 32 CdN 4 O 7 (2) and C 31.03 H 30.55 CdCl 0.24 N 4 O 5.52 (3) were successfully synthesized. CPs 1-2 and 3 are 2D networks and a 3D framework, which all display 3,5-connected topologies with different structural details. The effects of carboxylates with different carbon chains on the structure of the complexes were studied. Fluorescence experiments show that CPs 1-3 have good multi-functional sensing ability for metal cations (Fe 3+ ), anions (MnO 4 - , CrO 4 2- , Cr 2 O 7 2- ) and organochlorine pesticides (2,6-dichloro-4-nitroamine) with good anti-interference and recyclable characteristics. The possible sensing mechanism is also investigated in detail.