title: Amino-indanol-catalyzed asymmetric Michael additions of oxindoles to protected 2-amino-1-nitroethenes for the synthesis of 3,3'-disubstituted oxindoles bearing α,β-diamino functionality.
abstract: An organocatalytic asymmetric Michael addition reaction of 3-substituted oxindoles to protected 2-amino-1-nitroethenes has been developed. The reaction is catalyzed by a simple and readily available amino-indanol derivative and affords the desired products in very high yields (up to 99%) with excellent diastereoselectivities (up to >99:1) and very good enantioselectivities (up to 90%). Significantly, this study provides a general catalytic method for the construction of 3,3'-disubstituted oxindoles bearing α,β-diamino functionality as well as vicinal chiral quaternary/tertiary stereocenters. The potential utility of the protocol also had been demonstrated by gram-scale reaction and the versatile conversion of product. Furthermore, On the basis of the comprehensive experimental results and the absolute configuration of one of the Michael adducts, a work model was also proposed to explain the origin of asymmetric induction.
authors.affiliation: Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China.
authors.forename: Xiong-Li
authors.initials: XL
authors.lastname: Liu
authors.forename: Zhi-Jun
authors.initials: ZJ
authors.lastname: Wu
authors.forename: Xi-Lin
authors.initials: XL
authors.lastname: Du
authors.forename: Xiao-Mei
authors.initials: XM
authors.lastname: Zhang
authors.forename: Wei-Cheng
authors.initials: WC
authors.lastname: Yuan
mesh_terms: D000588:Amines / Q000737:chemistry*; D002384:Catalysis; D007189:Indans / Q000737:chemistry*; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry*; D009574:Nitro Compounds / Q000737:chemistry*; D000078183:Oxindoles
chemical_list: D000588:Amines; D007189:Indans; D007211:Indoles; D009574:Nitro Compounds; D000078183:Oxindoles; C116915:aminoindanol; C022960:2-oxindole