手性β-氨基醇的合成及其催化二乙基锌与醛的不对称加成反应

以烯烃为原料通过Sharpless不对称双羟化等多步反应合成7种手性β-氨基醇, 并将该类化合物用于催化二乙基锌和醛的不对称加成反应. 分别考察了影响对映选择性的催化剂结构、催化剂用量、溶剂、反应温度等各种因素. 当催化剂用量为5%、甲苯溶剂、在－10 ℃下、以(1S,2R)-(＋)-2-氨基-1,2-二苯基乙醇(1b)作催化剂时, 所得仲醇的对映体过量最高为85% ee, 产率高达100%.

Synthesis of Chiralβ-Aminoalcohols and Their Catalysis in the Asymmetric Addition of Diethylzinc to Aldehyde

Seven chiral β-aminoalcohols were synthesized by Sharpless asymmetric dihydroxylation and used as chiral catalysts in the asymmetric addition of diethylzinc to aldehydes．The effects of the amount and the structure of catalysts, solvent and reaction temperature on enantioselectivity were also studied. When the amount of catalyst was 5 mol% relative to aldehyde, solvent was toluene and reaction temperature was －10 ℃, the chiral ligand, 1S,2R-(＋)-2-amino-1,2-diphenylethanol (1b), efficiently catalyzed the asymmetric addition of diethylzinc to aldehydes with the yield up to 100% and enantiomeric excess up to 85%.