Application Study On The Synthesis Of Chiral β-pyridone Alcohol And γ-butyrolactone Derivatives Based On Asymmetric Hydrogen Transfer

The concept of chirality is becoming increasingly important in modern chemistry as mankind’s understanding of matter becomes more sophisticated,chiral compounds build the structural substrates of life.Among the chiral compounds,chiral pyridone derivatives andγ-butyrolactones are present in many areas of human production and life.Both types of chiral compounds have a wide range of applications and are important synthetic moieties for many biologically active compounds.Therefore,the search for a simple and efficient route for the synthesis of chiral pyridone derivatives andγ-butyrolactones is of great research interest.Currently,the synthesis of 1,3-bisexual compounds is challenging and asymmetric hydrogenation reactions are a common means of synthesis,but this method requires high experimental conditions and can be dangerous.The use of asymmetric transfer hydrogenation reactions to synthesise these two promising compounds for a wide range of applications has attracted our interest.A series of screening studies culminated in the successful one-pot,two-step synthesis of bipyridyl alcohol derivatives using asymmetric hydrogen transfer and a series of bipyridylγ-butyrolactones by dynamic kinetic resolution.Reduction of chiral ketones by asymmetric hydrogen transfer using Ru Cl[（S,S）-Ts DPEN]（Mesitylene）as a catalyst in CHCl₃ with HCOOH:Et₃N（5:2）as the hydrogen source,A series of biphasicβ-pyridone alcohols with high ee values（up to 99%）and high dr values（up to 99:1）were successfully synthesised in relatively good yields（up to 85%）.This reaction gives us our target product through a relatively simple substrate and is efficient.Based on asymmetric hydrogen transfer reactions by dynamic kinetic resolution in CH₂Cl₂ with HCOOH:DBU=5:6 as the hydrogen source.A range ofγ-butyrolactones with high ee values（up to 99%）and high dr values（up to 99:1）were eventually obtained in good yields（up to 89%）.The reaction conditions are safe and mild compared to hydrogen pressurisation and are in line with the green concept of modern chemical atomic economy.