Bisoxazoline and Bioxazoline Chiral Ligands Bearing 4-Diphenylmethyl Shielding Substituents. Diels-Alder Reaction of Cyclopentadiene with 3-Acryloyl-2-oxazolidinone Catalyzed by the Aqua Nickel(II) Complex
作者:Shuji Kanemasa、Kenji Adachi、Hidetoshi Yamamoto、Eiji Wada
DOI:10.1246/bcsj.73.681
日期:2000.3
4′-bis(diphenylmethyl)-2,2′-bioxazoline and 2,2′-isopropylidenebis(4-diphenylmethyloxazoline), and further to complexes with copper(II) trifluoromethanesulfonate and nickel(II) perchlorate hexahydrate. The nickel(II) aqua complex derived from the bisoxazoline effectively catalyzes the Diels-Alder reactions of cyclopentadiene with 3-acryloyl-2-oxazolidinone in high endo-selectivities and moderate enantioselectivities
Enantiopure 2-amino-3,3-diphenyl-1-propanol 已通过hidantoin 路线从二苯乙醛开始合成,然后通过手性 HPLC 进行后续的官能团转化和光学拆分。这种氨基醇可以转化为两个新的手性配体:4,4'-双(二苯基甲基)-2,2'-生物恶唑啉和 2,2'-异亚丙基双(4-二苯基甲基恶唑啉),并进一步与铜(II)复合三氟甲磺酸盐和高氯酸镍 (II) 六水合物。衍生自双恶唑啉的镍 (II) 水络合物通过方形平面过渡结构有效催化环戊二烯与 3-丙烯酰基-2-恶唑烷酮的狄尔斯-阿尔德反应,具有高内向选择性和中等对映选择性。