Ruthenium-Catalyzed Construction Of C-N Bonds From Biomass Molecules And Amines

Biomass is a renewable resource of a wide range of sources that are clean and environmentally friendly.Due to the large consumption of fossil energy,environmental problems are becoming more and more serious,so it is of great practical significance to rationally develop and utilize biomass resources.In the hydrogenolysis conversion of biomass-based compounds,it is often accompanied by cleavage of a plurality of C-C bonds and C-O bonds,resulting in low selectivity of the reaction and generation of various by-products.Therefore,it is very challenging to achieve efficiently and selectively cleavage of C-C bonds of biomass-based compounds to obtain useful chemicals.Using biomass-based compounds as building blocks,amines can be efficiently converted into oxygenated amines via hydrogen borrowing pathway.This is a challenging subject at present,which is significant for the sustainable synthesis of bioactive amines.Based on this,this paper starts from the renewable biomass raw materials and realizes the preparation of high-efficiency amines compounds catalyzed by ruthenium.In this thesis,the biomass is briefly introduced,and the research progress of the hydrogenolysis cleavage C-C bond of polyols and the borrowing hydrogen amination based on biomass-based compounds are reviewed.The main research contents and results in this thesis are as follows:1?The reaction of glycerol and amine use the new redox active catalyst which combine with ruthenium metal catalyst precursor,biphosphine ligand and N-Methyl-?2-thienylmethyl?amine ligand.?-amino alcohol compounds were obtained under the alkaline condition of t-BuOK?catalytic amount?.Amino acetone compounds were obtained under the acidic condition of CH₃COOH?catalytic amount?.Avarietyofaminesubstratescanbeconvertedtocorresponding amino-alcohol/ketone in medium to good yields.Meanwhile,it is believed that the reaction has gone through the key steps of the retro-aldol reaction and"hydrogen borrowing"reaction.2?The reaction of sugars/glycoalcohols?e.g.xylose,glucose,xylitol,etc.?and aromatic amine use the active catalyst which combine with ruthenium metal catalyst precursor and Xantphos diphosphonate ligand with rigid skeleton and N-hydroxyethyl products of aromatic amine were obtained.Highly selective cleavage of the C-C bond of the sugar/sugar alcohol was achieved during the reaction and a key intermediate of C2 glycolaldehyde was formed.The possible reaction pathways were proposed through gas chromatography,in situ NMR and other exploration experiments.It is considered that the C-C bond cleavage of xylose during the reaction is carried out by a retro-aldol reaction process.3?The reaction of xylitol and aromatic amine use the active catalyst which combine with ruthenium metal catalyst precursor and Xantphos phosphine ligand with rigid skeleton.A series of amine methylfuran derivatives were successfully synthesized under the acidic conditions.However,under the same conditions,the addition of 4A molecular sieve can promote the C-C cleavage of xylitol in the reaction process,and obtain the N-hydroxyethyl products of aromatic amine.The structure of the above target compound was determined by means of ¹H NMR,¹³C NMR and HRMS.