Premium
Mechanistic investigation inspired “on water” reaction for hydrobromic acid‐catalyzed Friedel–Crafts–type reaction of β ‐naphthol and formaldehyde
Author(s) -
Cao Shanshan,
Yuan Haiyan,
Yang Yang,
Wang Mang,
Zhang Xiaoying,
Zhang Jingping
Publication year - 2017
Publication title -
journal of computational chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.907
H-Index - 188
eISSN - 1096-987X
pISSN - 0192-8651
DOI - 10.1002/jcc.24877
Subject(s) - chemistry , catalysis , hydrobromic acid , acetonitrile , solvent , formaldehyde , nucleophile , photochemistry , molecule , friedel–crafts reaction , medicinal chemistry , organic chemistry
The mechanism of the HBr‐catalyzed Friedel‐Crafts‐type reaction between β ‐naphthol and HCHO was investigated by DFT to improve this reaction. The HBr‐H 2 O co‐catalyzed the preferential pathway undergoes the concerted nucleophilic addition and hydrogen shift, stepwise followed by H 2 O elimination and the CC bond formation. The origin of the high catalytic activity of HBr is ascribed to CH···Br − and OH···Br − interactions, which suggest that the active species is Br − . Moreover, water molecules efficiently assist in improving the activity of Br − . The computational results show that solvent polarity profoundly affects the activation barriers. To our delight, the activation barrier of the rate‐determining step for the favored pathway in water is comparable (0.6 kcal/mol difference) with that in acetonitrile. The experimental observation further confirmed our results and demonstrated that the title reaction can be successfully achieved “on water.” Therefore, we open a new efficient and green strategy for the synthesis of biphenol derivatives. © 2017 Wiley Periodicals, Inc.