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Updated: May 31, 2026

Hydrolysis of a Ni-Schiff-Base Complex Using Conditions Suitable for Retention of Acid-labile Protecting Groups
Published on: April 6, 2017
Hydrolytic stability of N-methyl-2,6-dimesityl-4,4'-pyrylogen bis-tetrafluoroborate
Tamer T El-Idreesy1, Edward L Clennan
1Department of Chemistry, Faculty of Science, Cairo University, Giza, Egypt. tamertawhid@yahoo.com
Abstract:
The synthesis and characterization of a new mesityl ring-substituted pyrylogen with a substantially decreased rate of reaction with water is reported. Computational and experimental data are presented that suggest that addition of water to the pyrylium ring of this highly sterically shielded pyrylogen is reversible. On the other hand, experimental data suggest that the overall hydrolysis of this new sterically shielded pyrylogen, but not the parent pyrylogen, is irreversible. Two potential explanations for this behavior are presented and discussed. These results provide important new information that can be used to design and synthesize new electron transfer sensitizers that can be used even in highly aqueous environments.
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