Stereoregulations of Pyrimidinone Based Chiral Auxiliary in Aldol and Alkylation Reactions: A Convenient Route to Oxyneolignans
作者:Mangilal Chouhan、Ratnesh Sharma、Vipin A. Nair
DOI:10.1021/ol302653g
日期:2012.11.16
a chiral auxiliary for asymmetric acetate and propionate aldol reactions, by generation of titanium and lithium enolates, affording excellent yields and stereoselectivities for syn and anti aldol diastereomers, respectively. High stereoselectivities were also obtained in lithium mediated alkylation reactions. The application of the auxiliary was exemplified in the asymmetric synthesis of a natural
(小号)-4-异丙基-1- phenyltetrahydropyrimidin-2(1 ħ) -酮的合成和评价为手性助剂为不对称乙酸酯和丙羟醛缩合反应,通过产生钛和锂烯醇化物,得到用于优异的产率和立体选择性合成和抗醛醇非对映异构体。在锂介导的烷基化反应中也获得了高的立体选择性。辅助助剂的应用在天然氧新木聚糖,(+)-(7 S,8 S)-4-羟基-3,3',5'-三甲氧基-8',9'-dinor-的不对称合成中得到了例证8,4'-氧新萘-7,9-二醇-7'-油酸。