Azidoacetic Acid Amides in the Synthesis of Substituted Arylidene‐1‐H‐imidazol‐5‐(4H)‐ones

Abstract

We present a novel efficient method for the synthesis of substituted arylidene‐1‐H‐imidazol‐5‐(4H)‐ones based on the use of azidoacetic acid amides. The proposed approach was successfully used for the preparation of three rows of target substances with different substituents in the imidazolone ring and benzylidene moiety. The presented methodology tends to be multipurpose and convenient for the introduction of substituents in any position.

The revelation of ESIPT behavior and fluoride response mechanism for (E)‐2‐(((1H‐benzo[d]imidazol‐2‐yl)‐imino)methyl)‐5‐(dimethylamino)‐phenol

“…Furthermore, the hydrogen bond strengthening or weakening could also be revealed based on monitoring the spectral shifts of vibrational modes involved in the formation of hydrogen bonds . The vibrational spectra of bip chromophore in the conjunct vibrational regions of the O‐H stretching mode have been shown in Figure .…”

“…Different from experimental results, the specific potential barrier of ESIPT and comprehend the mechanism of the ESIPT process can be provided based on quantum chemical computational study. And previous theoretical investigations have indicated that TDDFT/B3LYP calculated level should be efficient as far as the form of hydrogen‐transfer potential energy curves is concerned . It can provide qualitative energetic pathways for the ESIPT process of bip chromophore.…”

“…The geometric optimizations of bip , bip‐open and bip‐pt were performed using DFT in the S 0 state and using TDDFT in the S 1 state. Especially, the TDDFT method has become a very useful tool to theoretically investigate the hydrogen bonding interaction that occurs in the excited states . In addition, Becke's three‐parameter hybrid exchange functional with Lee–Yang–Parr gradient‐corrected correlation (B3LYP functional) was selected in both the DFT and TDDFT methods .…”

“…Till now, many different sensing mechanisms, such as intramolecular charge transfer (ICT), photo‐induced electron transfer (PET), fluorescence resonance energy transfer (FRET), and excited state proton transfer (ESPT) and so forth, are relevant with intra‐ or inter‐ molecular hydrogen bond. Particularly, the excited state inter‐ and intra‐ molecular proton transfer (ESIPT) reactions have been drawing great attention due to their unique photo‐physical and photo‐chemical properties.…”

“…Even though this sensor has weak fluorescence, it was reported that the anion‐binding adduct of bip is expected to be highly fluorescent based on ESIPT channel experimentally, however, the mechanism of bip in excited state is very limitted. In effect, experimental spectroscopic techniques, such as steady‐state absorption spectroscopy, fluorescence spectroscopy and time resolved fluorescence spectroscopy, just provide the indirect information about photo‐physical and photo‐chemical properties . Up to now, the theoretical investigations about the bip are very scarce in addition to the experiments.…”