6235-15-0Relevant academic research and scientific papers
Biocompatible ionic liquid [Betaine][H2PO4] as a reusable catalyst for the substitution of xanthen-9-ol under solvent-free conditions
Feng, Wanlu,Li, Lingjun,Wang, Jianji,Wang, Tong,Zhu, Anlian
, p. 31662 - 31669 (2020)
An ionic liquid, namely [Betaine][H2PO4], was found to be an efficient catalyst for the direct substitution reaction of xanthen-9-ol with different nucleophiles under solvent-free conditions. This catalytic system is easy to be operated and the following work-up procedure is simple, with the ionic liquid catalyst reusable for at least five cycles at a high catalytic activity level. In addition, the ionic liquid is easy to prepare and its raw materials are inexpensive and have good biocompatibility. Therefore, our study presents an intriguing and sustainable protocol for the direct substitution of alcohol. This journal is
Manganese(III)-Mediated Carbon-Carbon Bond Formation in the Reaction of Xanthenes with Active Methylene Compounds
Nishino, Hiroshi,Kamachi, Hironori,Baba, Harumi,Kurosawa, Kazu
, p. 3551 - 3557 (2007/10/02)
Oxidation of xanthenes with manganese(III) acetate in the presence of active methylene compounds such as 1,3-dicarbonyl compounds, malononitrile derivatives, acetone, and nitromethane selectively gives 9-substituted xanthene derivatives in good yields.A similar oxidation of thioxanthene also yields 2-(9-thioxanthenyl)-1,3-dicarbonyl compounds in 57-91 percent yields.The obtained 2-(9-xanthenyl)-1,3-dicarbonyl compounds are readily converted to 2-(9-xanthenylidene)-1,3-dicarbonyl derivatives using manganese(III) complexes or 2,3-dichloro-5,6-dicyano-1,4-benzoquinone.The mechanisms for the formation of 9-substituted xanthenes are discussed on the basis of the reaction intermediates, the electron-donating substituent effect on the xanthene ring system, effect of additives, and comparison with a reaction of radical-trapping reagents.
