We compare the electronic structure of two metal-centered tetramethyldibenzo-tetraazaannulene (TMTAA) macrocyclic complex molecules: 5,7,12,14- tetramethyl-2,3:9,10-dibenzo[b,i]-1,4,8,11-tetraazacyclotetradecine nickel (II) and 5,7,12,14-tetramethyl-2,3:9,10-dibenzo[b,i]-1,4,8,11-tetraazacyclotetradecine cobalt (II). The experimental gap between the highest occupied molecular orbital to the low...

A convenient, efficient and practical procedure for the synthesis of 1-amidoalkyl 2-naphthols is described by condensation of aromatic aldehydes with amides and 2-naphthol in the presence of P2O5/SiO2 as an efficient catalyst. Moreover, in the present of this catalyst, the synthesis of 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes is studied by co...

The synergistic solvent extraction of 14 trivalent lanthanoids (except Pm) with 1-phenyl-3-methyl-4-benzoyl-5pyrazolone(HP) and dibenzo-18-crown-6 (DB18C6) or dibenzo-24-crown-8(DB24C8) in 1, 2-dichloroethane has been studied. It was found that in the presence of HP alone the lanthanoids have been extracted as LnP3∙HP and in the presence of mixtures of HP and crown ethers (S) − as LnP3∙S. On th...

Determination of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in fly ash and cinders collected from nine municipal incinerators in Japan was made. The concentrations of PCDDs and PCDFs in this study were generally in the same range as those in Europe and North America. However, the rather different congener composition compared with those published already...

Two novel host materials, 3-(dibenzo[b,d]furan-4-yl)-9-(4,6-diphenyl-1,3,5-triazin-2-yl)-9H-carbazole (BFTC) and 3-(dibenzo[b,d]thiophen-4-yl)-9-(4,6-diphenyl-1,3,5-triazin-2-yl)-9H-carbazole (BTTC) were designed and synthesized. These two compounds exhibited excellent physical properties with high thermal stabilities and reasonable HOMO–LUMO energy levels. Both of them were applied to fabricat...

The discovery of the crown ethers stemmed from efforts to control the catalytic activity of vanadium and copper by complexation with multidentate ligands. The first crown ether, 2,3,11,12-dibenzo-1,4,7,10,13,16-hexaoxacyclo-octadeca-2,11-diene, was obtained in 0.4% yield during an attempt to prepare a phenolic ligand from catechol and bis(2-chloroethyl)ether. This compound, which complexed with...

Abstract A series of tetrazole-linked dibenzo[b,f][1,4]oxazepines is synthesized through a short sequence involving an Ugi tetrazole reaction. The intermediate undergoes potassium carbonate mediated SNAr cyclization, followed by oxidation to afford the target tricyclic heterocyclic scaffold. optimization, scope and limitations this two-step efficient methodology are investigated. 1000-member li...