A new small molecule gelator and 3D framework ligator of lead(ii). Issue 42 (3rd September 2015)

• Record Type: Journal Article
• Authors: Knichal, Jane V.; Gee, William J.; Burrows, Andrew D.; Raithby, Paul R.; Wilson, Chick C.
• Is Part Of: CrystEngComm. Volume 17:Issue 42(2015)
• Page Start: 8139
• Page End: 8145
• Publication Date: 2015-09-03
• Subjects: Crystals -- Periodicals; Crystal growth -- Periodicals; Crystallography -- Periodicals; Cristaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Cristallographie -- Périodiques; 548
• DOI: 10.1039/c5ce01689d
• Languages: English
• ISSNs: 1466-8033

Abstract

Abstract : A new allene dicarboxylate ligand reacts with hydrated lead(ii ) acetate in DMF to yield either a crystalline 3D framework or a metallogel dependent on the reaction temperature. Abstract : Reacting equimolar quantities of 5-allenyl-1, 3-benzenedicarboxylic acid (H2 abd ) with lead(ii ) acetate trihydrate in N, N -dimethylformamide (DMF) under solvothermal conditions results in formation of a metallogel with a critical gelation percentage of 1% w/v. Elemental analysis performed on the gel provided a molecular composition ratio of [Pb(abd )(H2 O)] n (1 ). Viewing the gel by scanning electron microscopy (SEM) identified an entangled network of cross-linked nano-fibres. 1 H-NMR aliquots of hydrated lead(ii ) acetate added to a solution of H2 abd in deuterated DMF allows inferences to be made about solution-state behaviour that occurs during the initial gel aggregation stage. Under non-solvothermal conditions, combining H2 abd and hydrated lead(ii ) acetate resulted in formation of single crystals suitable for X-ray diffraction, which were identified as a 3D coordination polymer with composition [Pb(abd )(DMF)] (2 ). Structural features observed within this 3D coordination polymer provide the basis for assigning the molecular structure to the fibrils present within gel1 . This assertion is supported by comparable vibrational profiles taken from a sample of dried gel1 to that of crystalline2, and the matching of early solution-state 1 H-NMR spectroscopic trends to later solid-state observations.