Enantioselective Synthesis of Highly Functionalized Dihydrofurans through Copper-Catalyzed Asymmetric Formal [3+2] Cycloaddition of β-Ketoesters with Propargylic Esters
作者:Fu-Lin Zhu、Ya-Hui Wang、De-Yang Zhang、Jie Xu、Xiang-Ping Hu
DOI:10.1002/anie.201405857
日期:2014.9.15
An enantioselective synthesis of highly functionalized dihydrofurans through a copper‐catalyzed asymmetric [3+2] cycloaddition of β‐ketoesters with propargylic esters has been developed. With a combination of Cu(OTf)2 and a chiral tridentate P,N,N ligand as the catalyst, a variety of 2,3‐dihydrofurans bearing an exocyclic double bond at the 2 position were obtained in good chemical yields and with
通过铜催化β-酮酸酯与炔丙基酯的不对称[3 + 2]环加成反应,开发了高度官能化的二氢呋喃的对映选择性合成。通过将Cu(OTf)2和手性三齿P,N,N配体作为催化剂的组合,可以制得各种在2位带有环外双键的2,3-二氢呋喃,化学收率高且高对映选择性。环外双键可以高度非对映选择性的方式氢化,生成不寻常的cis -2,3-二氢呋喃衍生物,从而进一步扩大了这种转化的范围。