No abstract

Copper(I) catalysed oxidative conversion of imidazopyridines into N‐pyridinylamides has been achieved via tandem C−C and C−N bond cleavages under oxidative reaction conditions. The methodology has wide substrate scope and products were formed in good to excellent yields. This method is suitable for the oxidative conversion of both C‐3 functionalized as well as non‐functionalized imidazopyridines

Compounds with (NHC) → E coordination bond represent a family of chemical species with significant interest and their chemistry is being explored over the past 15 years, where NHC and E represent N‐heterocyclic carbene and main group elements, respectively. NHOs (N‐heterocyclic olefins) are special among these because of the (NHC) → CR2 interaction. NHOs carry nucleophilic exocyclic carbon and many interesting reactions of NHOs are due to this character. Alkylated imidazole oximes (cationic, found useful in medicinal chemistry) [(NHC) → C(H) = NOH]+ carry NHC unit as a functional group. Similarly, the corresponding nitroso‐N‐heterocyclic olefins [(NHC) → C(R)NO] also carry NHC as a functional unit. It is important to establish the interactions between the NHC unit and the rest of the molecule in these species. Density functional theory (DFT) was employed to explore the electronic structure details of a series of oximes and nitroso NHOs. The results indicate that a structure with (NHC) → C coordination interaction can be considered as one of the resonance structures of these species.

N‐Heterocyclic imines (NHIs) are versatile compounds with the general formula (NHC)=NR. NHIs with R=NO (known as nitroso N‐heterocyclic imines, NNHIs) have special importance in ozone depletion protection as well as in drug discovery. The electronic structure of these compounds has not been thoroughly explored. A few experimental studies indicated that the (NHC)=N bond is weak; a few other studies indicated that the N−N bond is weak in these species. It is important to establish the chemical bond variations in NNHIs. Density functional theory (DFT) studies have been carried out on NNHIs to explore the chemical bonding details. A new derivative containing NNHI unit and caffeine moiety has been experimentally generated and the structure was studied using XRD.