294646-72-3Relevant academic research and scientific papers
Excited-state amine-imine double proton transfer in 7-azaindoline
Chou, Pi-Tai
, p. 7818 - 7829 (2000)
Ground-state thermodynamics and excited-state amine/imine tautomerism in 7-azaindoline (7AZD) mediated by hydrogen bond formation have been studied by means of absorption and emission spectroscopies. The association constants in cyclohexane (298 K) were determined to be 80, 2.5 × 102, and 7.8 × 102 M-1, for the formation of 7AZD dimer, 7AZD/azacyclohexanone, and 7AZD/acetic acid dual hydrogen-bonded complexes, respectively. The 7AZD/acetic acid complex undergoes a fast (? 3 × 109 s-1) excited-state double proton transfer (ESDPT) reaction, resulting in a prominent imine-like tautomer emission. Proton-transfer isomers of 7AZD have been identified through syntheses and spectral characterization of various 7AZD methyl derivatives. In contrast, ESDPT is prohibited in cases of 7AZD dimer and 7AZD/azacyclohexanone hydrogen-bonded complex. The results, in combination with a comparative study on 7-azaindole, generalize the amine/imine tautomerism, which can be fine-tuned by the length of π electron conjugation coupled with types of associated guest molecules, further supporting the proposed catalytic-versus-noncatalytic model for the ESDPT reaction.
Co(II)-Catalyzed Regioselective Pyridine C-H Coupling with Diazoacetates
Xie, Haisheng,Shao, Youxiang,Gui, Jiao,Lan, Jianyong,Liu, Zhipeng,Ke, Zhuofeng,Deng, Yuanfu,Jiang, Huanfeng,Zeng, Wei
supporting information, (2019/05/08)
A Co(II)-catalyzed pyridyl C-H bond carbenoid insertion with α-diazoacetates has been realized. This transformation features a highly regioselective C-C bond formation at the C3-position of pyridines, providing an efficient access to diverse α-aryl-α-pyri
