Divergent synthesis of N-alkyl-3-sulfonylindoles and N-alkyl-3-sulfanylindoles from 2-alkynyl-N,N-dialkylanilines and sulfonyl hydrazides has been described.
Synthesis of 3-Sulfenyl- and 3-Selenylindoles by the Pd/Cu-Catalyzed Coupling of <i>N</i>,<i>N</i>-Dialkyl-2-iodoanilines and Terminal Alkynes, Followed by <i>n</i>-Bu<sub>4</sub>NI-Induced Electrophilic Cyclization
作者:Yu Chen、Chul-Hee Cho、Feng Shi、Richard C. Larock
DOI:10.1021/jo9014003
日期:2009.9.4
palladium/copper-catalyzed crossing coupling of N,N-dialkyl-ortho-iodoanilines and terminalalkynes and subsequent electrophilic cyclization of the resulting N,N-dialkyl-ortho-(1-alkynyl)anilines with arylsulfenyl chlorides or arylselenyl chlorides. The presence of a stoichiometric amount of n-Bu4NI is crucial to the success of the electrophilic cyclization. A variety of 3-sulfenyl- and 3-selenylindole derivatives
3-亚硫基-和 3-硒基吲哚可通过两步法合成,包括钯/铜催化的N , N - 二烷基-邻 -碘苯胺和末端炔烃的交叉偶联以及随后所得N , N - 的亲电环化二烷基-邻-(1-炔基)苯胺与芳基硫基氯或芳基硒基氯。存在化学计量的n -Bu 4NI 对于亲电环化的成功至关重要。各种带有烷基、乙烯基、芳基和杂芳基取代基的 3-亚苯基和 3-硒基吲哚衍生物已经以良好到极好的产率(高达 99%)制备。通过使用N,N-二苄基-邻-碘苯胺,已成功制备了3-硫基-N - H-吲哚。此外,3-磺酰基-和3-亚磺酰基吲哚也已通过相应的3-亚磺酰基吲哚的轻松氧化成功制备。
CuBr-Promoted Tandem Cyclization/Trifluoromethylation of 2-Alkynylanilines: Efficient Synthesis of 3-Trifluoromethylindoles
A new efficient strategy for the synthesis of 3‐trifluoromethyl‐indoles was developed through tandemcyclization/trifluoromethylation of 2‐alkynylanilines and Umemoto's reagent under effect of CuBr. The reaction features the use of cheap copper salt, mild reaction conditions and high yield of products. The preliminary mechanism study indicates the solvent dimethylacetamide acts as the role of dealkylation
Herein, we demonstrated that 2-alkynyldimethylamines easily cyclize in EtOH according to a 5-endo-dig annulation into 2-substitutedindoles without the aid of any additives or any metal catalysts to activate the triple bond. Thus, a variety of functionalized 2-styrylindoles, 2-arylindoles, 2-alkynylindoles, and 2-alkylindoles were prepared in high to excellent yields according to an environmentally
Palladium-Catalyzed Coupling of<i>ortho</i>-Alkynylanilines with Terminal Alkynes Under Aerobic Conditions: Efficient Synthesis of 2,3-Disubstituted 3-Alkynylindoles
作者:Bo Yao、Qian Wang、Jieping Zhu
DOI:10.1002/anie.201205596
日期:2012.12.3
Two nucleophiles, one triple bond: Under aerobic conditions, palladium‐catalyzed direct coupling of o‐alkynylanilines and terminalalkynes took place smoothly to afford the 2,3‐disubstituted 3‐alkynylindoles 3 in good to excellent yields. The intermediate A was characterized and a retro‐aminopalladation of B was observed for the first time.