作者:Joseph C. Sloop、Paul D. Boyle、Augustus W. Fountain、William F. Pearman、Jacob A. Swann
DOI:10.1002/ejoc.201001451
日期:2011.2
suggest a single, chelated cis-enol isomer that is conjugated with the aryl ring. In polar aprotic solvents, nonfluorinated aryl β-diketones equilibrate rapidly from the chelated cis-enol form to a tautomeric mixture of cis-chelated enol and a substantial proportion of the diketone form, trifluoromethylated aryl β-diketones show only limited equilibration from the chelated cis-enol to the diketone form
使用克莱森和亲电氟化方法制备氟化芳基β-二酮。这些化合物的酮-烯醇和烯醇-烯醇互变异构在固态、纯液体和极性非质子溶液中通过结晶学和光谱学进行了检测。纯液体光谱测量以及选定的缺电子芳基 β-二酮的单晶 X 射线晶体学结果表明,存在与芳环共轭的单一螯合顺式烯醇异构体。在极性非质子溶剂中,非氟化芳基 β-二酮从螯合顺式烯醇形式迅速平衡为顺式螯合烯醇和大部分二酮形式的互变异构混合物,三氟甲基化芳基 β-二酮仅显示有限的螯合顺式平衡-烯醇到二酮形式,