Synthesis Of 2-((2-phenylquinolin-3-yl)oxy)ethan-1-ol Compounds Based On Aromatic Amines

Quinoline compounds are important N-heterocyclic compounds which are widely used in pharmaceutical chemistry and organic synthesis.Synthesis of quinolines or modification of quinoline skeleton has been becoming a hot topic study.The traditional method based on name reaction of formation of quinolines has always been the main method.In recent years,in order to be more consistent with the concept of green chemistry,many convenient and efficient methods for the synthesis of quinoline derivatives have been continuously reported under metal-free catalysis,photocatalysis,and microwave condition by improving name reaction condition.2-((2-arylquinolin-3-yl)oxy)ethanols were obtained using 1,4-dioxane and aromatic amines as raw materials under iodine-containing compounds as catalysts,peroxides as oxidants in this paper.Detailed research was described as follows:(1)A series of 2-((2-arylquinolin-3-yl)oxy)ethanols are prepared from aromatic alcohols,aromatic amines and 1,4-dioxane using NIS as catalysis and DCP as an oxidant with moderate to good yields.1,4-Dioxane acts both as a carbon source and as a solvent,and provides a 2-(vinyloxy)ether-1-ethanol group.This transformation includes breakage of multiple bonds(C-H,N-H,and C-O bonds)and formation of multiple bonds(C-C,C-N,and O-H bonds).The research on reaction mechanism has shown the target product of were prepared through oxidation of aryl methanol to aldehyde,oxidative dehydrogenation of amines,free-radical addition and cyclization of 1,4-dioxane,ring opening reaction,dehydrogenation aromatization reaction to generate quinoline skeleton.This transformation could involve a radicalmediated tandem cyclization reaction instead of typical [4+2] cycloaddition reactions of imines with olefins.It will provide a novel strategy for the synthesis of 2-((2-arylquinolin-3-yl)oxy)ethanol compounds.The application of the target product was also explored.The obtained quinoline product was used to synthesize aryl vinyl ether by two-step reaction such as bromination,elimination reaction.Compared with the previous synthesis method,this transformation has advantages such as cheap and readily avilable materials,simple and mild reaction conditions,short reaction path.So this method has potential application prospect.(2)On the basis of developing the strategy of synthesis of 2-((2-arylquinolin-3-yl)oxy)ethanol compounds by aromatic alcohols,aromatic amines and 1,4-dioxane,the acetic acid mediated synthesis of 2-([2,2’-biquinolin]-3-yloxy)ethanol only using aniline and 1,4-dioxane as raw materials was also explored.2-([2,2’-biquinolin]-3-yloxy)ethanol can be obtained by using aniline as nitrogen source using ammonium iodide as catalyst and TBHP as oxidant by “one pot” method.1,4-dioxane provides multiple carbon sources and a 2-(vinyloxy)ether-1-ethanol group.This method will afford a new route for synthesis of 2-([2,2’-biquinolin]-3-yloxy)ethanol because of simple reaction system and cheap and readily avilable materials.