Arslan Nevin, Ercan Selami, PİrİnÇÇİoĞlu Necmettin
Department of Chemistry, Faculty of Science, Dicle University, Diyarbakır Turkey.
Department of Field Crops, Faculty of Agriculture, Şırnak University, İdil, Şırnak Turkey.
Turk J Chem. 2020 Apr 1;44(2):335-351. doi: 10.3906/kim-1908-3. eCollection 2020.
This work involves a facile synthesis of three (S) -proline-based organocatalysts with C2 symmetry and their effects in enantioselective aldol reaction of acetone with substituted aromatic aldehydes. Moderate enantioselectivities (up to 61% ee) were obtained depending on the nature of the substituents on the aryl ring. Computational calculations at HF/6-31 + G(d) level were employed to underline the enantioselectivity imposed by all the organocatalysts. Higher calculations at B3LYP/6-311 ++ G(d,p) scrf=(solvent=dichloromethane)//B3LYP/6-31 + G(d) levels of theory were also performed for the aldol reaction of acetone with benzaldehyde and 4-nitrobenzaldehyde catalyzed by 1. The computational outcomes were consistent with those produced by experimental results and they were valuable to elucidate the mechanism for the observed stereoselectivity.
这项工作涉及一种简便的合成方法，用于制备三种具有C2对称性的基于（S）-脯氨酸的有机催化剂，以及它们在丙酮与取代芳香醛的对映选择性羟醛反应中的作用。根据芳环上取代基的性质，获得了中等的对映选择性（高达61% ee）。采用HF/6-31 + G(d)水平的计算来强调所有有机催化剂施加的对映选择性。还对由1催化的丙酮与苯甲醛和4-硝基苯甲醛的羟醛反应进行了B3LYP/6-311 ++ G(d,p) scrf=(溶剂=二氯甲烷)//B3LYP/6-31 + G(d)理论水平的更高计算。计算结果与实验结果一致，对于阐明观察到的立体选择性机制很有价值。
