Formic Ion Research Articles

Synthesis, structure and characterization of two borates templated by in situ prepared organics

Two unusual organic templated borates, [Al(C3H12N2)(C2H7N)]·[B5O10] (1) and [Zn(HCOO)(1,2-dap)2]·[B5O7(OH)4] (2) were synthesized under solvothermal conditions ([HCOO]−=formic ion; 1,2-dap=1,2-diaminopropane). The obtained 1 and 2 borates were characterized by using elemental analysis, FTIR, PXRD, TG, and single-crystal X-ray diffraction. 1 crystallizes in the Pbca space group and shows a 3D anionic framework based on AlO4 and B5O10 clusters. Interestingly, there are two kinds of organic amines in the structure: one was 1, 2-dap, while the other was ethylamine from the in situ reaction of 1,2-dap. 2 crystallizes in the P-1 space group, and consists of a [Zn(HCOO)(1,2-dap)2]+ cation and [B5O6(OH)4]− polyanion, the presence of [HCOO]− suggests the in situ decomposition of DMF (DMF=N, N-Dimethylformamide).

Relation between catalyst structure and selectivity of the oxidative coupling of 2,6-dimethylphenol in the presence of copper complexes: studies using EPR and NMR

Relation between catalyst structure and selectivity of the oxidative coupling of 2,6-dimethylphenol, I, into poly[oxy-(2,6-dimethyl)-1,4-phenylene], II, an important industrial polymer, in the presence of copper( II) complexes with acetate or formate and pyridine or piperidine in chloroform and chloroform + toluene solutions has been studied. Variations in the structure of the catalyst during various steps of the catalytic process have been elucidated using EPR and NMR. Six different types of Cu( II) complexes have been observed and their roles in the catalytic process have been identified. Intermediates that control reaction selectivity towards the desired polymeric product II seem to be mixed Cu( II) complexes with monomeric and oligomeric phenolate ions, acetic or formic ion and amines. The rate-determining step of oxidative coupling in steady-state conditions seems to be electron transfer from phenolate ions to the Cu( II) atom in these complexes. The selectivity is enhanced at high concentrations of these complexes, since in these conditions the monomeric phenoxyl radicals formed in the reaction mixture react mainly with coordinated phenolate and polyphenolate ligands to yield finally II, rather than recombining to form 3,3',5,5'-tetramethyldiphenoquinone, III, which is the main side product of the reaction. Complexes with oligomeric phenolate ligands seem to provide better selectivity than complexes with monomeric ones, since for the former complexes intramolecular electron transfer does not produce the monomeric phenol radicals necessary to make compound III.

ケイフッ酸系黒色クロムメッキ浴の添加剤

Bath composition and plating conditions of black chromium plating bath containing hydrogen silicofluoride were given in the previous report (Part 1). The addition of hydrogen silicofluoride to this bath was intended to give higher blackness and evenness in coloration but these effects were not com- plete in the results.Then, effects of further addition agents to the above bath were studied and found that the addition of nitric and formic ions among acid radicals and barium ion among metallic ions was most effective for color in platings; and no other agents were effective.Bath composition and plating conditions for giving the most even and black coloration were as follows:Cr2O3……300g/lH2SiF6……1g/lAddition agents……3-5g/lBath temperature……above 10°CDk……30-50amp./dm2