The direct formation of 2,2-disubstituted 1,3-cyclopentanedione compounds by a Lewis acid catalysed reaction with 1,2-bis(trimethylsilyloxy)cyclobutene proceeds in good to excellent yields with unhindered ketals, but steric hindrance reduces the yields considerably. A carbonyl group α or β to the ketal, or a carbon–carbon double bond α to the ketal, stops the reaction completely. Orthoesters do not give geminally acylated products in synthetically useful yields.
通过路易斯酸催化的反应,使用1,2-双(三甲基硅氧基)环丁烯与没有受阻碍的缩酮,直接形成2,2-二取代的1,3-环戊二酮化合物,产率良好至优秀,但立体位阻显著降低了产率。位于缩酮α或β位置的羰基,或者与缩酮α位置相邻的碳-碳双键会完全停止反应。正酯不会以合成有用的产率产生双酰化产物。