Suppressed β-Effect of Silicon in 3-Silylated Monocyclic β-Lactams: The Role of Antiaromaticity
作者： Subhendu Sekhar Bag , Rajen Kundu , Amit Basak , Zdenek Slanina
DOI: 10.1021/OL902411R
关键词: Chemistry 、 Kinetics 、 Medicinal chemistry 、 Antiaromaticity 、 Silicon 、 Photochemistry 、 β lactams 、 Substituent
摘要: The β-stabilizing effect of silicon substituent at C-3 on a C-4 cation and radical in the 2-azetidinone systems is studied using NMR kinetics. While β-effect virtually nonexistent case cation, foiled (only 3-fold rate enhancement) observed for intermediate. From both experimental theoretical studies, it demonstrated that antiaromaticity playing prime role suppressing silicon.
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