Ab Initio Studies on the Preferred Site of Protonation in Cytisine in the Gas Phase Water

International Journal of Molecular Sciences

Ewa D. Raczyńska¹  Mariusz Makowski²  El់ieta Górnicka³ 

[1] Department of Chemistry, Agricultural University (SGGW), 02-776 Warsaw, Poland;Faculty of Chemistry, University of Gdańsk, 80-952 Gdańsk, Poland;Interdisciplinary Department of Biotechnology, Agricultural University (SGGW), 02-776 Warsaw, Poland

关键词: Cytisine;    Site of protonation;    Ab initio calculations;    PCM;    Gas phase and Solution;   

DOI  :  10.3390/i6010143

来源: mdpi

【 摘 要 】

Ab initio calculations (HF, MP2, DFT for isolated and PCM for solvated molecules) were performed for cytisine (1) and its model compounds: N-methyl-2-pyridone (2) and piperidine (3). Among three heteroatomic functions (carbonyl oxygen, pyridone and piperidine nitrogens) considered as the possible sites of protonation in 1, surprisingly the carbonyl oxygen takes preferentially the proton in the gas phase whereas in water the piperidine nitrogen is firstly protonated. For model compounds, the piperidine nitrogen in 3 is more basic than the carbonyl oxygen in 2 in both, the gas phase and water.

【 授权许可】

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