Layered dipyridylamide coordination polymers from in situ lactonization of 2-carboxycinnamic acid

Functionalized Aromatic Dicarboxylate Ligands in Uranyl–Organic Assemblies: The Cases of Carboxycinnamate and 1,2-/1,3-Phenylenedioxydiacetate

“…The difference in synthetic procedures leading to 5 and 6 was simply the substitution of acetonitrile for DMF as cosolvent, and hydrolysis of acetonitrile produces a weak acid/weak base mixture (CH 3 CO 2 H/NH 3 ) with presumably a rather similar influence on pH to that produced from DMF (HCO 2 H/HN­(CH 3 ) 2 ); however, the rates would presumably be different and it appears that in the case of complex 6 a different reaction, an oxidation leading to oxalate, was more important. Complex 2 contains both the original ligand ccn 2– and the lactone 1,3-dihydro-3-oxo-1-isobenzofuranacetate (dibf – ) formed in situ from cyclization of ccn 2– , as previously reported, and found in several complexes. , In all cases, the uranyl/dicarboxylate ligand ratio was 7:10 so as to favor the formation of an anionic species and the incorporation of structure-directing counterions, but this ratio is found in none of the complexes formed, with the 1:1 ratio being observed instead in all cases but that of complex 7 for which it is 1:2. This however does not necessarily prevent the incorporation of counterions or additional metal ions due to the presence in several cases of anionic coligands, nitrato in 1 , dibf – in 2 , formato in 4 , hydroxo in 5 , and oxalato in 6 .…”

“…The emission spectrum of complex 4 is even more anomalous, since these uranium emission peaks are completely absent and only a broad emission band is seen. The ligand present in complex 2 resulting from cyclization of 2-carboxycinnamate is in fact an example of an organic luminophore known to form broad-band emissive complexes with Zn II and Cd II but with emission wavelengths much shorter than those of the broad bands in 2 , 4 , and 8 . Excitation spectra were recorded for complexes 2 , 4 , and 8 and are shown in Figure , where it is apparent that a broad band lies at lower energy than the uranyl excited-state manifold.…”

Metal‐Dependent Topologies and Water Aggregations in Copper and Nickel Carboxycinnamate Coordination Polymers with a Long‐Spanning Dipyridylamide Ligand

“…Compound 2 crystallizes in the acentric orthorhombic space group P2 1 2 1 2 with the Flack parameter [25] of -0.013 (14) indicating enantiomeric purity within the crystal, within experimental error. The asymmetric unit of compound 2 contains a divalent nickel atom, a cca ligand, a full 4-bpfp ligand, two bound water molecules, and net three water molecules of crystallization.…”

“…Reaction of divalent metal nitrates with H 2 cca and 3-pyridylisonicotinamide (3-pina) caused in situ rearrangement of the acid precursor to the anionic lactone 1,3-dihydro-3-oxo-1-isobenzofuranacetate (dibf), with formation of an isostructural series of (4,4) grid coordination polymers [M(3-pina) 2 (dibf) 2 ] n (M = Zn, Cd, Co, Mn, Ni). [14] Scheme 2. Binding modes of the cca ligands in 1 and 2.…”

“…The π bond within the long carboxylate arm of cca also proved susceptible to in situ reaction chemistry under hydrothermal conditions, likely via nucleophilic attack at antibonding π* orbitals. Reaction of divalent metal nitrates with H 2 cca and 3‐pyridylisonicotinamide (3‐pina) caused in situ rearrangement of the acid precursor to the anionic lactone 1, 3‐dihydro‐3‐oxo‐1‐isobenzofuranacetate (dibf), with formation of an isostructural series of (4, 4) grid coordination polymers [ M (3‐pina) 2 (dibf) 2 ] n ( M = Zn, Cd, Co, Mn, Ni) 14…”