54657-81-7Relevant academic research and scientific papers
Selective cyclodimerization and cyclotrimerization of acetals bearing electron-withdrawing groups catalyzed by lewis acids
Maeda, Sayuki,Obora, Yasushi,Ishii, Yasutaka
experimental part, p. 4067 - 4072 (2009/12/24)
Acetais like 3,3-dlethoxyproplonate bearing electron-withdrawing groups were found to undergo cyclodimerization and cyclotrimerization in the presence of Lewis acids to give coumalates and 1,3,5-trisubstituted benzenes. The selectivity of these products depended on the Lewis acids employed. For instance, ethyl coumalate was obtained from, ethyl 3,3diethoxypropionate in high selectivity under the influence of d-block Lewis acids like FeCl3, whereas triethyl 1,3,5-benzenetricarboxylate was obtained in preference to ethyl coumalate under the influence of lanthanoid Lewis acids like GdCl3, Various coumalates were synthesized by the FeCl3catalyzed cross-cyclodimerization of acetals with active methylene compounds, From 4,4-diniethoxy-2-butanone, however, 1,3,5-triacetylbenzene, which is difficult to prepare regioselectively by conventional methods, was formed in quantitative yield under the influence of AlCl3, This reaction would provide a very convenient route to 1,3,5-triacetylbenzene,
