Synthesis of 2-Amino-1-cyanoazulenes: Substituent Effect on 2H-Cyclohepta[b]furan-2-ones toward the Reaction with Malononitrile
摘要:
3-Substituted 2-amino- 1-cyanoazulene derivatives were prepared by the reaction of 2H-cyclohepta[b]furan-2-ones with malononitrile in the presence of triethylamine as a base. The great influence of the substituent at their 3-position on the reactivity to form the 2-aminoazulene derivatives was revealed. The intramolecular charge transfer (ICT) characters of 2-amino- 1-cyano-3-vinylazulenes were investigated by UV/Vis spectroscopy and theoretical calculations. The structure of compounds 13b and 14b was clarified by single crystal X-ray analysis.
Synthesis and Redox Behavior of Cyanovinyl-Substituted 2H-Cyclohepta[b]furan-2-ones
摘要:
Cyanovinyl-substituted 2H-cyclohepta[b]furan-2-ones 3, 4, 5 and 7 were prepared by the Wittig, Knoevenagel and electrophilic substitution reaction, respectively. The intramolecular charge-transfer (ICT) interactions between the 2H-cyclohepta[b]furan-2-one ring and cyanovinyl acceptor moiety were investigated by UV/Vis spectroscopy and theoretical calculations. The redox behavior of these novel compounds was examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Significant color changes in these compounds were observed under electrochemical reduction conditions by visible spectroscopy.