ABSTRACT
The interaction of iodine as a sigma-acceptor with two derivatives of polyamidoamine dendrimers (donor), 1,8-naphthalimide polyamidoamine (PAM1) and 4-piperidino-1,8-naphthalimide polyamidoamine (PAM2) have been investigated spectrophotometrically at room temperature in chloroform. The results indicate the formation of two CT-complexes [(PAM1)I](+)I(3)(-) and [(PAM2)(2)I](+)I(3)(-) with molar ratios of 1:2 and 1:1, respectively. The formation of these two complexes are in good agreement with their elemental analysis, infrared measurements and photometric titration plots based on the characteristic absorption bands of I(3)(-) ion around 280 and 360 nm. Moreover the formation of triiodide ion, I(3)(-), in both of the two complexes was supported by measuring their spectra in the far-infrared region. Three characteristic bands are observed at 125, 110 and 75 cm(-1) due to nu(as)(I-I), nu(s)(I-I) and delta(I(3)(-)), respectively, with C(2v) symmetry.
Subject(s)
Amides/chemistry , Amines/chemistry , Iodides/chemistry , Polymers/chemistry , Absorption , Electrons , Molecular Structure , Spectrum Analysis , TitrimetryABSTRACT
Cobalt(II) carbonate, CoCO3.4H2O and lead(II) carbonate, PbCO3.2H2O were synthesis by a new simple method during the reaction of aqueous solutions of CoX2 (X=Cl-, NO3- and CH3COO-) and PbX2 (X=NO3- or CH3COO-), respectively, with urea at approximately 85 degrees C for 2 h. The infrared spectra of the reaction products clearly indicates the absence of the bands due to coordinated urea, but show the characteristic bands of ionic carbonate. A general mechanisms describing the formation of cobalt and lead carbonates are suggested.
Subject(s)
Carbonates/isolation & purification , Cobalt/isolation & purification , Lead/isolation & purification , Carbonates/chemical synthesis , Spectrophotometry, Atomic , Spectroscopy, Fourier Transform Infrared , UreaABSTRACT
The reaction of ferric(III) acetylacetonate (donor), Fe(acac)3, with iodine as a sigma-acceptor and with other different pi-acceptors have been studied spectrophotometrically at room temperature in chloroform. The pi-acceptors used in this investigation are 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), p-chloranil and 7,7',8,8'-tetracyanoquinodimethane (TCNQ). The results indicate the formation of 1:1 charge-transfer complexes with a general formula, [Fe(acac)3 (acceptors)]. The iodine complex was shown to contain the triiodide species, [Fe(acac)3]2I(+)I3-, based on the electronic absorptions as well as on the Far-infrared absorption bands characteristic for the non-linear triiodide species, I3-, with C2v symmetry. The proposed structure of this complex is further supported by thermal and middle infrared measurements.
