Barbituric acid as a new locking fragment in macrocyclization: synthesis and structural characterization of [aqua(perchlorato)(2′,4′,6′-trioxohexahydropyrimidine-5′-spiro-6-1,4,8,11- tetraazacyclotetradecane)copper(II)] perchlorate hydrate
摘要:
The reaction of [Cu(danda)](2+) (danda = 3,7-diazanoqane-1,9-diamine) with formaldehyde and barbituric acid resulted in a new macrocyclic compound, bearing barbituric acid as a spiro substituent which was characterized by spectral and potentiometric methods, cyclic voltammetry and single-crystal X-ray diffraction.
DOI:
10.1039/dt9960002017
作为产物:
描述:
5,7-diphenyl-1,4,8,11-tetraazacyclotetradecane-6,6-dicarboxylic acid diethyl ester copper(II) diperchlorate 在
water 作用下,
以
not given 为溶剂,
生成 {Cu(1,9-diamino-3,7-diazanonane)}(2+)
Structural Properties of Cyclopentanone-Bridged Bis-Macrocyclic Ligand Dicopper(II) Complexes in the Solid and in Solution: A Successful Test of the MM-EPR Method
作者:Peter Comba、Marion Kerscher、Yaroslaw D. Lampeka、Lutz Lötzbeyer、Hans Pritzkow、Lyudmyla V. Tsymbal
DOI:10.1021/ic026265r
日期:2003.6.1
The copper(II)-assisted condensation of 2,3,2-tet (3,7-diazanonane-1,9-diamine) with formaldehyde and cyclopentanone yields the mono- and bis-macrocyclic Mannich condensation products L-1 and L-2, as well as the Schiff-base product L-3, all with cyclam-type tetraaza macrocycles, coordinated to copper(II). The combination of molecular mechanics and EPR spectroscopy (MM-EPR) reveals that all three isomers of [Cu-2(L-2)(OH2)(n)](2) (n = 0-4), with the expected trans-III (R,R,S,S) configuration of the 14-membered tetraaza macrocycles, are of similar stability, and that the isomer whose structure is solved by X-ray crystallography has a different structure in solution.