Protection And De-protection Of Hydroxyl Groups Without Solvent And Preparation Of Chiral Amino Alcohols

Solvent-free organic synthesis technology has been widely concerned for the characteristics of economy,green,high efficiency,easy implemental and operation.This paper mainly focuses on the protection and de-protection of hydroxyl groups under solvent-free condition.Firstly,we used TMSCl(heating to reflux)to directly protect 10 kinds of hydroxyl compounds with representative structures,and the yield of our tests reached 89-95%.Compared with traditional silicon-ether protection,this method can avoid the using of solvent and catalyst and simplified the experimental procedure.Secondly,we used KF as desiliconization agent and PEG600 as phase transfer catalyst to test the De-protection of hydroxyl groups.The yield of our tests reached 91~96%.In general,this method is economic,efficient,and environmental friendly,which has industrial application value.Chiral amino alcohols are a kind of important molecular compound with optical activity,diversified structures,and good selectivity.They have been widely applied in the fields of materials,pharmaceutical,asymmetric synthesis,fine chemicals and so on.In this paper,the chiral amino alcohols were prepared by the reduction of chiral amino acids.In order to reduce the reaction conditions and improve the reaction efficiency,we first prepared the chiral amino acid-aluminum ion chelate,and then Li/tert-butanol was used to reduce the chelate to prepare chiral amino alcohols,the yield of our products reached 74~89%.In summary,this reduction is simple,efficient and suitable for large-scale industrial production.