铱催化中氮茚衍生物的Friedel-Crafts类型不对称烯丙基取代反应  

Ir-Catalyzed Enantioselective Friedel-Crafts Type Allylic Substitution of Indolizines

作　　者：杨普苏 刘晨旭 张文文 游书力[1,2] Pusu Yang;Chen-Xu Liu;Wen-Wen Zhang;Shu-Li You(State Key Laboratory of Organometallic Chemistry,Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,Shanghai 200032,China;Chang-Kung Chuang Institute,East China Normal University,Shanghai 200062,China)

机构地区：[1]中国科学院上海有机化学研究所，金属有机化学国家重点实验室,上海200032 [2]华东师范大学庄长恭研究所,上海200062

出　　处：《化学学报》2021年第6期742-746,共5页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos.21821002,21961132002);上海市科学技术委员会(No.19590750400)资助.

摘　　要：本工作报道了金属铱催化烯丙醇与中氮茚衍生物Friedel-Crafts类型的不对称烯丙基取代反应.该方法在温和条件下,以优秀的收率以及对映选择性控制合成了一系列C3位烯丙基化的中氮茚衍生物,为构建手性中氮茚化合物提供了一条新策略.Indolizine is an important N-containing heterocyclic nucleus and their derivatives display interesting biological activities.The development of synthetic methods towards indolizine derivatives has attracted extensive attention.Despite the rapid growth in this area,asymmetric synthesis of indolizine derivatives has been rarely reported.Ir-catalyzed asymmetric allylic substitution reaction is an efficient method for the enantioselective construction of C―C or C―X bonds,furnishing terminal olefins bearing a stereogenic center at the allylic position with excellent regio-and enantioselectivities.In this re-gard,various electron-rich arenes,including indoles,pyrroles,naphthols,have been applied as the nucleophiles via Friedel-Crafts type process in the allylic substitution reactions.As a class of constitutional isomers of indoles,indolizines are now demonstrated as suitable nucleophiles in transition-metal-catalyzed allylic substitution reactions.Herein,an iridium-catalyzed enantioselective allylic substitution of allylic alcohol with indolizine is reported.A broad range of 3-allylindolizines were accessed with high yields(83%~95%)and excellent enantioselectivities(95%~>99%ee).A general procedure for the asymmetric allylation of indolizines is described in the following:A flame-dried Schlenk tube was cooled to room tem-perature and filled with argon.To this flask were added[Ir(cod)Cl]2(4.0 mg,0.006 mmol,3 mol%)and(S)-L1(12.1 mg,0.024 mmol,12 mol%).After the flask was evacuated and refilled with argon for three times,freshly distilled dichloro-methane(DCM)(2 mL)were added.After the mixture was stirred for 15 min at room temperature,indolizines(0.2 mmol,1.0 equiv.),allylic alcohols(0.4 mmol,2.0 equiv.)and(PhSO2)2NH(18.0 mg,0.06 mmol,30 mol%)were added under argon atmosphere.The reaction mixture was stirred at room temperature and monitored by thin-layer chromatography(TLC).Once indolizines were consumed,the reaction was diluted with water(5 mL),and the mixture was extracted with EtOAc(10 mL×3).The organic layer was

关 键 词：铱催化 烯丙基取代反应 对映选择性 中氮茚 烯丙醇 

分 类 号：O626[理学—有机化学]