Bi-SO3H-functionalized room temperature ionic liquids based on bipyridinium: highly efficient and recyclable catalysts for the synthesis of naphthalene-condensed oxazinone derivatives

作者：Wang, Yuanyuan^*; Zhou, Junlong; Liu, Kun; Dai, Liyi

来源：RSC Advances, 2013, 3(25): 9965-9972.

DOI：10.1039/c3ra00133d

• Catalytic performance
• Function values
• Functionalized ionic liquids
• Hydrogen bond networks
• Minimum-energy geometry
• Recyclable catalyst
• Room temperature ionic liquids
• Sulfonic acid groups

Several bi-SO3H-functionalized room temperature ionic liquids were synthesized and their catalytic performances for the synthesis of naphthalene-condensed oxazinone derivatives were studied theoretically, as well as experimentally. Compared with traditional single-SO3H-functionalized ionic liquids, less catalyst and higher yields are the key features of this methodology. Hammett function values and the minimum-energy geometries of bi-SO3H-functionalized ionic liquids were calculated and the results revealed that the acidities and catalytic activities of ionic liquids in the synthesis of naphthalene-condensed oxazinone derivatives were influenced by their structures. There are strong hydrogen bond networks in these bi-SO3H-functionalized ionic liquids. The H-O bond of the sulfonic acid groups was lengthened to different levels compared with the one in the isolated cation. The ionic liquid [(PS)(2)bPy][OTf](2) with the shortest H-O bond distance had the strongest hydrogen bond and hence showed the strongest acidity and the highest catalytic activity.

• 出版日期2013
• 单位华东师范大学