A STUDY ON HETEROCYCLIC SYNTHESIS VIA CYCLIZATION AS A KEY REACTION FROM HETERO ATOM-CONTAINING UNSATURATED COMPOUNDS

1. 利用手性路易斯酸（如三酸铜）-双恶唑啉和双亚胺配合物催化剂，研究了多种噻唑二烯，如硫代查尔酮、α、β-不饱和二硫酯、α-芳基亚甲四酮、烷基取代和樟脑衍生的噻唑二烯与手性或非手性n -丙烯酰氯杂唑啉的高非对映选择性和对映选择性的杂diols - alder反应。由环加合物衍生的一种同手性环状硫化物，在碱的存在下催化醛和亚胺与卤化物的对映选择性Corey-Chaykovsky环氧化反应和叠氮化反应。交叉共轭杂三烯（N， O， S）的立体选择性、二烯透射的Diets-Alder反应得到了环状杂环。在初始环加成反应中，根据氮扎特烯上取代基的不同，氮扎特烯与反应性亲二酚类试剂如甲苯异氰酸酯、烯酮和乙烯醚发生反应。第二环加成与多种二亲化合物进行了正常的需要电子的Diels-Alder反应。以亚胺磷烷与异氰酸酯为原料，通过aza-Wittig反应制备了含烯烃、Michael受体、羧基酯、缩醛或环氧环的功能化碳二酰亚胺的串联环化策略，从而方便地合成了咪唑喹啉、咪唑咪唑、咪唑嘧啶、咪唑喹唑啉、咪唑噻嗪、嘧啶苯并噻嗪、喹唑啉苯并噻嗪等多种环融合的氮杂环化合物。和diazepinoquinolines。该方法包括分子内胺亲核加成的初始环化到cumulene碳上，然后通过与内部官能团反应使新形成的胺第二次环化。

1. Highly diastereoselective and enantioselective hetero Diels-Alder reactions of a variety of thiabutadienes such as thiochalcones, α, β-unsatturated dithioesters, α-arylmethylenethiotetralones, and alkyl-substituted and camphor-derived thiabutadienes with a chiral or achiral N-propenoyloxazolidinone dienophile, using chiral Lewis acids (e.g., copper triflate)-bis(oxazoline) and bis(imine) complex catalysts for the latter, have been developed. A homochiral cyclic sulfide derived from the cycloadduct catalyzed the enantioselective Corey-Chaykovsky epoxidation and aziridination of aldehydes and imines with halides in the presence of base.2. Stereoselective, diene-transmissive hetero Diets-Alder ractions of cross-conjugated heterotrienes (N, O, S) to give ringfused heterocycles have been developed. The azatrienes reacted for the initial cycloaddition with reactive dienophiles such as tosylisocyanates, ketenes and vinyl ethers, depending on the substituents on the azatrienes. The second cycloaddition underwent normal electron-demanding Diels-Alder reaction with a variety of dienophiles.3. Tandem cyclizations strategy of functionalized carbodiimides bearing an alkene, a Michael acceptor, a carboxy ester, an acetal or an epoxy ring, which were prepared by the aza-Wittig reaction of iminophosphoranes with isocyanates, have been developed for facile synthesis of a variety of ring-fused nitrogen-heterocyclic compounds such as imidazo-quinolines, imidazoimidazoles, imidazopyrimidines, imidazoquinazolines, imidazothiazines, pyrimidobenzothiazines, quinazolinobenzothiazines, and diazepinoquinolines. The method includes the initial annulation of an intramolecular amine-nucleophilic addition to the cumulene carbon, followed by the second cyclization of a newly formed amine by reacting with an inner functional group.