Synthesis of a new chiral amino phosphine ligand and its application in the asymmetric allylic alkylation (AAA) reaction

This article describes the synthesis of a new chiral amino phosphine ligand based on an amino naphthol starting material, which is resolved efficiently by using l-tartaric acid. The asymmetric induction of the ligand in the Pd(0)-catalyzed allylic substitution of 1,3-diphenylprop-2-en-1-yl acetate with dimethyl malonate was investigated. Good yields and enantiomeric excesses up to 78% of the product were obtained.

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(S,aR) (−)-1-(1,2,3,4-Tetrahydro-2-methylisoquinolin-1-yl)naphthalen-2-yl trifluoromethanesulfonateC21H18NO3SF3[α]D20=-81.55 (c 1.8, CH2Cl2)Source of chirality: enantiomerically pure starting materialAbsolute configuration: (S,aR)

(mTHIQ-NAP) (S,aR)-1,2,3,4-Tetrahydro-2-methyl-1-(2-(diphenylphosphino)naphthalen-1-yl)isoquinolineC32H27NP[α]D20=-130.5 (c 1.4, CHCl3)Source of chirality: enantiomerically pure starting materialAbsolute configuration: (S,aR)

(mTHIQNOL) (S,aR) (−)-1-(2-Methyl-1,2,3,4-tetrahydroisoquinolin-1-yl)naphthalen-2-olC20H20NO[α]D20=-304.7 (c 0.4; CH2Cl2).Source of chirality: resolutionAbsolute configuration: (S,aR)