手性方酰胺配体的合成及催化二乙基锌对醛的不对称加成反应

Synthesis of new chiral squaric acid amides and enantioselective addition of diethylzinc to aryl aldyhyde catalyzed by ligands

手性1,2-环己二胺和1,2-二苯基乙二胺分别与2倍以上物质的量的方酸二酯反应可得含C2对称的手性方酰胺配体4和6以及少量单取代产物5.当1,2-二苯基乙二胺与等物质的量的方酸二正丁酯的乙醇溶液在回流温度下反应时则得关环产物7.上述新配体可用于催化二乙基锌对醛的不对称加成反应,产物仲醇的化学得率和ee值分别为45%～98%和25%～71%,所有新配体的结构均被IR,1HNMR,MS和元素分析所证实.

The chiral squaric acid amides ligands 4 and 6, which are C2 symmetry compounds, were prepared by 1,2cyclohexanediamine and 1,2diphenyl1, 2ethandiamine reacting respectively with more than two times equivalent squaric acid diesters. If 1,2diphenyl1, 2ethandiamine reacting with the same equivalent dibutyl squarate in alcohol in the condition of reflux, the cyclizing compound 7 would be obtaind. The new ligands above, which structures were identified by means of IR, 1 H NMR, MS and elemental analysis, could be used as catalyst in asymmetric addition reaction of diethylzinc to aryl aldehyde in 45%～98% yield and with 25%～71% enantiomeric excesses.