Chiral multidentate ligand, and application thereof in asymmetric hydrogenation

1 . A chiral multidentate ligand selected from the group consisting of L1-L10, shown as:

2 . A method of preparing the chiral multidentate ligand of claim 1 , comprising:

(S1) subjecting compound (M1) containing an amino-protecting group and compound (M2) to undergo a condensation reaction to obtain compound (M3); and subjecting the compound (M3) to amine deprotection in the presence of a deprotection reagent to obtain compound (M4); wherein when the amino-protecting group is a t-butyloxy carbonyl (Boc) group, the deprotection reagent is selected from the group consisting of trifluoroacetic acid, methanesulfonic acid, hydrochloric acid, sulfuric acid, and phosphoric acid; and when the amino-protecting group is a benzyloxycarbonyl (Cbz) group, the amino-protecting group is removed under the catalysis of Pd/C catalysts or Pd (OH) 2 /C catalyst in a hydrogen atmosphere;

(S2) subjecting compound (1) to deprotonation by butyl lithium and phosphorization to produce compound (2); and substituting a dimethylamino group in the compound (2) with an acetoxy group to obtain compound (3); and

(S3) reacting the compound ( 3 ) with the compound (M4) in the presence of triethylamine to produce chiral multidentate ligands L1-L9, wherein an enantiomer L10 of a chiral multidentate ligand L3 is synthesized from corresponding chiral raw materials through a method of preparing the chiral multidentate ligand L3, as shown in the following reaction scheme:

3 . The method of claim 2 , wherein the deprotection reagent is trifluoroacetic acid or hydrochloric acid.