Synthesis Of Chiral β-Arylselanyl Alcohols And β-Arylselanyl Amines

Selenium-containing organic molecules have been the focus of selenium research,which is widely used in chemistry,biology,medicine,materials and other fields,with important implications for human health and the development of natural science.Chiral alcohols are considered as key intermediates in the synthesis of optically active medicines,natural products,and agrochemicals.Nitrogen-containing compounds are important structural motifs in natural products,functional materials,and pharmaceutical formulations.In this paper,selenium atoms were introduced into chiral alcohols and nitrogen-containing compounds.Two categories of organic selenium compounds were synthesized to provide a foundation for the development and application of organic selenium.1.Synthesis of chiral β-arylselanyl alcohols via asymmetric transfer hydrogenationMain synthetic methods for chiral β-selenyl alcohols are kinetic resolution of racemic alcohols or asymmetric reaction of organoselenium reagents with epoxides,olefins,or aldehydes.Low yields and limited substrate adaptability are common issues in kinetic resolution.Asymmetric reactions which have single strategy often require sensitive,expensive,or uncommon reagents,harsh reaction conditions,or lengthy reaction times.Therefore,it is still necessary to develop a simple and mild method with good substrate scope for the synthesis of chiral β-selenyl alcohols.A highly efficient transfer hydrogenation of α-aryl selenomethyl ketones,using readily available chiral diamine-derived ruthenium complex as a catalyst and a mixture of formic acid and triethylamine as a hydrogen source under ambient conditions,is described.A wide range of chiral β-selenyl alcohols was obtained in 90%-99%ee values and moderate to good yields including two natural product derivatives.The practicability is also demonstrated by a gram-scale synthesis and downstream derivatization.2.Synthesis of β-arylselanyl amines via aminoselenation of alkenesGeneral strategies for the synthesis of β-selenyl amines include reductive amination ofα-selenyl ketones,aminoselenation of alkenes,ring-opening selenation of azepanes,and hydrogenselenylation of imines.Efficient synthesis of amide,sulfonamide and nitrogen-containing heterocyclic β-selenyl amines have been achieved under facile,mild and metal-free reaction conditions.However,the current methods for synthesizing arylamineβ-selenyl amines require metal reagents,which is easy to retain metal,and some reactions have harsh conditions and dangerous or unavailable reagents.Therefore,developing a new method to synthesize arylamine β-selenyl amines is still highly desirable.Drawing inspiration from the iodine-catalyzed synthesis of benzotriazoles and sulfonamide β-selenyl amines,this paper employs iodine as a catalyst for the aminoselenation of aromatic alkenes with diaryl diselenide and anilines at room temperature,resulting in the construction of 37 β-selenyl amino anilines.This protocol features mild reaction conditions,simple operation,broad substrate range,and metal-free.