La(OTf)3-catalysed one-pot synthesis of pyrazole tethered imidazo[1,2-a]azine derivatives and evaluation of their light emitting properties was written by Sharma, Shubham;Paul, Avijit Kumar;Singh, Virender. And the article was included in New Journal of Chemistry in 2020.SDS of cas: 17355-75-8 The following contents are mentioned in the article:
A facile and efficient protocol has been unfolded towards the diversity-oriented synthesis of highly fluorescent pyrazole C-3(5) tethered imidazo[1,2-a]azines via an La(OTf)3 catalyzed one-pot multicomponent assembly of pyrazole carbaldehydes, 2-aminoazines and isonitriles. This present protocol offers several advantages such as multiple bond formation in a single step, low catalyst loading, short reaction time, appreciable atom economy, good functional group tolerance, scalability and easy to perform reaction conditions. The optical properties of pyrazolyl imidazo[1,2-a]azines were also studied, and they exhibited an excellent fluorescence quantum yield (ΦF up to 83%). This study involved multiple reactions and reactants, such as Ethyl 1,5-diphenyl-1H-pyrazole-3-carboxylate (cas: 17355-75-8SDS of cas: 17355-75-8).
Ethyl 1,5-diphenyl-1H-pyrazole-3-carboxylate (cas: 17355-75-8) belongs to pyrazole derivatives. Pyrazole is a weak base, with pKb 11.5 (pKa of the conjugated acid 2.49 at 25 °C).Pyrazole used as a ligand to prepare organometallic compounds. The presence of both electronegative nitrogen atoms in the pyrazole ring reduces the electron density of the C3- and C5-positions leaving electron density of C4-position unaltered. Thus the C4-position is vulnerable to electrophilic attack. The C3 electrophilic-position may undergo deprotonation in the presence of a strong base leading to ring opening.SDS of cas: 17355-75-8
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics