Journal of Molecular Structure, cilt.1272, 2023 (SCI-Expanded)
© 2022Imidazopyrimidines have some interconvertible tautomeric forms. Regioselectivities were resolved for N-benzylations of some 8-(substituted phenyl)chloropurines with benzyl or 4-chlorobenzyl bromides under basic conditions (K2CO3) in DMF. It was observed that, while N-benzylation of 2‑chloro-8-(4-substituted)phenylpurines occur on the five-membered imidazole ring (1a, 1b, 2a and 2b) to the contrary, same alkylation reaction of 6‑chloro-8-(4-fluorophenyl)purine (3) occurs on the six-membered pyrimidine ring (4). Their structures were established by combination of 1H–1H NOE (Nuclear Overhauser Effect Spectroscopy, NOESY) and 1H–13C/15N HMBC (Heteronuclear Multiple Bond Correlation) methods. X-ray crystallographic data of compound 4 was also used for further confirmation.