Ketopinic Acid Derived Bis(hydroxy amides) as Cheap, Chiral Ligands for the Enantioselective Ethylation of Aromatic Aldehydes
作者:Tomás de las Casas Engel、Beatriz Lora Maroto、Santiago de la Moya Cerero
DOI:10.1002/ejoc.200901391
日期:2010.3
available (+)-ketopinic acid and protic diamines, are promising, cheap, chiral ligands for the synthetically valuable, enantioselective addition of organozinc reagents to carbon electrophiles. A series of ligands of this type, having key structural differences, has been synthesized and tested in the enantioselective ethylation of benzaldehydes and (E)-cinnamaldehyde, in order to gain information on
易于获得的 C 2 - 和假 C 2 - 对称双(羟基酰胺),衍生自市售的 (+)-酮品酸和质子二胺,是有前景的、廉价的、手性配体,用于有机锌试剂的合成有价值的对映选择性加成到碳亲电子试剂。在苯甲醛和(E)-肉桂醛的对映选择性乙基化中合成并测试了一系列具有关键结构差异的此类配体,以获得有关配体效率起源的信息。获得的结果允许定义用于设计改进的廉价配体的特权结构模式,并支持为作用催化物种和控制过渡态提出的有趣模型。事实证明,最有效的配体比市售的 (-)-MIB 效率低;尽管如此,还是获得了令人印象深刻的效率水平,这应该会引起人们对这种廉价配体的兴趣。