Synthetic and structural aspects of the chemistry of saturated polyaza macrocyclic ligands bearing pendant coordinating groups attached to nitrogen

The environmental and societal consequences of the increasing levels of carbon dioxide in our atmosphere are among the most significant challenges society currently faces. Carbon dioxide utilizatio...

Opportunities and Challenges for Catalysis in Carbon Dioxide Utilization

Self-assembly under hydrothermal conditions has been employed to synthesize several novel uranium-containing polymeric materials in the pyridinedicarboxylic acid (pydc) system. Uranium containing coordination polymers were synthesized utilizing 2,3-pyridinedicarboxylic acid (2,3-pydc), 2,4-pyridinedicarboxylic acid (2,4-pydc) and 2,6-pyridinedicarboxylic acid (2,6-pydc) as the organic linker. Furthermore, several bimetallic compounds were also synthesized, U–M–2,6-pydc (M = Cu, Ag, Pb). A new secondary building unit for uranium(VI) compounds has also been realized in compound 4 [(UO2)2(C7H3NO4)(O)(H2O)] through tetramer building units edge shared to form one-dimensional chains. Presented herein will be the syntheses, crystal structures and fluorescent properties of these uranium-containing compounds.

Synthesis, structure and fluorescent studies of novel uranium coordination polymers in the pyridinedicarboxylic acid system

The reaction of nucleobases (adenine or purine) with a metallic salt in the presence of potassium oxalate in an aqueous solution yields one-dimensional complexes of formulas [M(μ-ox)(H2O)(pur)]n (pur = purine, ox = oxalato ligand (2-); M = Cu(II) [1], Co(II) [2], and Zn(II) [3]), [Co(μ-ox)(H2O)(pur)0.76(ade)0.24]n (4) and {[M(μ-ox)(H2O)(ade)]·2(ade)·(H2O)}n (ade = adenine; M = Co(II) [5] and Zn(II) [6]). Their X-ray single-crystal structures, variable-temperature magnetic measurements, thermal behavior, and FT-IR spectroscopy are reported. The complexes 1−4 crystallize in the monoclinic space group P21/a (No. 14) with similar crystallographic parameters. The compounds 5 and 6 are also isomorphous but crystallize in the triclinic space group P1 (No. 2). All compounds contain one-dimensional chains in which cis-[M(H2O)(L)]2+ units are bridged by bis-bidentate oxalato ligands with M...M intrachain distances in the range 5.23−5.57 A. In all cases, the metal atoms are six-coordinated by four oxalato oxygen at...

http://www.ehu.eus/proman/documents/2004IC43-5761GarciaTeran5_001.pdf

One-dimensional oxalato-bridged Cu(II), Co(II), and Zn(II) complexes with purine and adenine as terminal ligands.

Hydroxo- and methoxo-bridged tetranuclear copper(II) complexes of the tetramacrocyclic ligand 1,2,4,5-tetrakis(1,4,7-triazacyclonon-1-ylmethyl)benzene (Ldur), have been prepared from [Cu4Ldur(H2O)8](ClO4)8.9H2O (1). Addition of base to an aqueous solution of 1 gave [Cu4Ldur(mu2-OH)4](ClO4)4 (2). Diffusion of MeOH into a DMF solution of 2 produces [Cu4Ldur(mu2-OMe)4](ClO4)4.HClO4.2/3MeOH (3), a complex which hydrolyzes on exposure to moisture regenerating 2. The structurally related azido-bridged complex, [Cu4Ldur(mu2-N3)4](PF6)4.4H2O.6CH3CN (4), was produced by reaction of Ldur with 4 molar equiv of Cu(OAc)2.H2O and NaN3 in the presence of excess KPF6. Compounds 2-4 crystallize in the triclinic space group P1 (No. 2) with a = 10.248(1) A, b = 12.130(2) A, c = 14.353(2) A, alpha = 82.23(1) degrees, beta = 80.79(1) degrees, gamma = 65.71(1) degrees, and Z = 1 for 2, a = 10.2985(4) A, b = 12.1182(4) A, c = 13.9705(3) A, alpha = 89.978(2) degrees, beta = 82.038(2) degrees, gamma = 65.095(2) degrees, and Z = 1 for 3, and a = 12.059(2) A, b = 12.554(2) A, c = 14.051(2) A, alpha = 91.85(1) degrees, beta = 98.22(1) degrees, gamma = 105.62(1) degrees, and Z = 1 for 4. The complexes feature pairs of isolated dibridged copper(II) dimers with "roof-shaped" Cu2(mu2-X)2 cores (X = OH-, OMe-, N3-), as indicated by the dihedral angle between the two CuX2 planes (159 degrees for 2, 161 degrees for 3, and 153 degrees for 4). This leads to Cu.Cu distances of 2.940(4) A for 2, 2.962(1) A for 3, and 3.006(5) A for 4. Variable-temperature magnetic susceptibility measurements indicate weak antiferromagnetic coupling (J = -27 cm(-1)) for the hydroxo-bridged copper(II) centers in 2 and very strong antiferromagnetic coupling (J = -269 cm(-1)) for the methoxo-bridged copper(II) centers in 3. Pairs of copper(II) centers in 4 display the strongest ferromagnetic interaction (J = 94 cm(-1)) reported thus far for bis(mu2-1,1-azido)-bridged dicopper units. Spectral measurements on a neat powdered sample of 4 at 33.9 GHz or 90 Ghz confirm the spin-triplet ground state for the azido-bridged copper(II) pairs.

Syntheses, crystal structures, magnetic properties, and EPR spectra of tetranuclear copper(II) complexes featuring pairs of "roof-shaped" Cu2X2 dimers with hydroxide, methoxide, and azide bridges.

Reaction of CuI, 1,4,7-triallyl-triazacyclononane (L), and sodium tetraphenylboron with either CsHCO3 in dry methanol or CO2 in slightly moist methanol results in the formation of the oxalate anion, which is isolated as [LCu(μ-C2O4)CuL][Ph4B]2 (1).

Fixing carbon dioxide with copper: crystal structure of [LCu(mu-C2O4)CuL][Ph4B]2 (L = N,N',N"-triallyl-1,4,7-triazacyclononane).

The crystal structure and magnetic properties of
[Cu
 2
L
 m
 
(OH)
 2
][BPh
 4

]
 2
 has been determined; L
 m
 is one of
three new binucleating ligands based on 1,4,7-triazacyclononane and
o-, m- or p-xylene.

Synthesis of a series of novel binucleating ligands based on1,4,7-triazacyclononane and o-, m- andp-xylene: crystal structure of the µ-hydroxy-bridgeddicopper(II) complex[Cu2Lm(OH)2][BPh4]2 [Lm = α,α′-bis(N-1,4,7-triazacyclononane)-m-xylene]

Macrocycles with a single pendant arm: synthesis of N-R-(1,4,7-triazacyclononane) [L, R = 4-but-1-ene; L′, R = 3-prop-1-ene]: Synthesis of the CuI complex [CuL]I and synthesis and crystal structure of the CII complex [CuL2][BPh4]2 and the μ-hydroxy bridged CII dimer [LCu(μ-OH)2CuL] [BPh4]2

A general route for the synthesis of triazacyclononane functionalised with one, two or three pendant phosphine arms: crystal structure of [Zn2L2Cl3][ClO4], L =N-(diphenylphosphinopropyl)-1,4,7-triazacyclononane

A General Route for the Synthesis of Triazacyclononane Functionalised with Pendant Phosphane Arms − Crystal Structures of [NiL1Cl(HOEt)][ClO4] and [NiL1(NCS)2] with L1 = N‐(Diphenylphosphanylpropyl)‐1,4,7‐triazacyclononane

Paul A. Lovatt

Papers

Fixing carbon dioxide with copper: crystal structure of [LCu(mu-C2O4)CuL][Ph4B]2 (L = N,N',N"-triallyl-1,4,7-triazacyclononane).

Synthesis of a series of novel binucleating ligands based on1,4,7-triazacyclononane and o-, m- andp-xylene: crystal structure of the µ-hydroxy-bridgeddicopper(II) complex[Cu2Lm(OH)2][BPh4]2 [Lm = α,α′-bis(N-1,4,7-triazacyclononane)-m-xylene]

Macrocycles with a single pendant arm: synthesis of N-R-(1,4,7-triazacyclononane) [L, R = 4-but-1-ene; L′, R = 3-prop-1-ene]: Synthesis of the CuI complex [CuL]I and synthesis and crystal structure of the CII complex [CuL2][BPh4]2 and the μ-hydroxy bridged CII dimer [LCu(μ-OH)2CuL] [BPh4]2

A general route for the synthesis of triazacyclononane functionalised with one, two or three pendant phosphine arms: crystal structure of [Zn2L2Cl3][ClO4], L =N-(diphenylphosphinopropyl)-1,4,7-triazacyclononane

A General Route for the Synthesis of Triazacyclononane Functionalised with Pendant Phosphane Arms − Crystal Structures of [NiL1Cl(HOEt)][ClO4] and [NiL1(NCS)2] with L1 = N‐(Diphenylphosphanylpropyl)‐1,4,7‐triazacyclononane