Structural assignment of adenine aggregates in CDCl3.
We reinvestigated the self-association of 9-substituted adenine derivatives in CDCl3 solutions and present the infrared spectra of 9-ethyladenine and N-methyl-9-ethyladenine and its aggregates in the spectral regions between 1500 and 1800 cm(-1) and between 2700 and 3600 cm(-1). Wavelength dependent absolute extinction coefficients of the monomer and dimers are presented on the basis of a simple deconvolution method. Comparison of the deconvoluted dimer spectra with quantum chemical calculations allows for a structural assignment of the two dimer structures that coexist in 9-ethyladenine/CDCl3 solutions. In contrast, the dimer spectrum of N-methyl-9-ethyladenine is dominated by a single isomer.
Biemann
Lars
L
Institut für Physikalische Chemie, Heinrich-Heine Universität Düsseldorf, 40225 Düsseldorf, Germany.
Häber
Thomas
T
Maydt
Daniela
D
Schaper
Klaus
K
Kleinermanns
Karl
K
D000225:Adenine / Q000031:analogs & derivatives / Q000737:chemistry*; D002627:Chemistry, Physical / Q000379:methods*; D002725:Chloroform / Q000737:chemistry*; D019281:Dimerization; D006860:Hydrogen Bonding; D008956:Models, Chemical; D008968:Molecular Conformation; D015394:Molecular Structure; D013055:Spectrophotometry, Infrared / Q000379:methods*; D013816:Thermodynamics
C001172:9-ethyladenine; D002725:Chloroform; D000225:Adenine