Diastereodivergent Enantioselective [8 + 2] Annulation of Tropones and Enals Catalyzed by N-Heterocyclic Carbenes
作者:Shoulei Wang、Carles Rodríguez-Escrich、Mauro Fianchini、Feliu Maseras、Miquel A. Pericàs
DOI:10.1021/acs.orglett.9b00906
日期:2019.5.3
N-Heterocycliccarbene catalysts are used for the first time to mediate asymmetric [8 + 2] cycloadditions of enals with tropones. The kinetic [8 + 2] cis-cycloadducts can be epimerized to their trans analogues by simply using increased amounts of base and longer reaction times. Substituted tropones are also tolerated, and the cycloaddition products can be derivatized by hydrogenation or methanolysis
ON THE REACTION OF<i>N</i>-VINYLIMINOPHOSPHORANES. A NOVEL ROUTE TO 1-AZAAZULENE RING SYSTEM UTILIZING AZA-WITTIG REACTION
作者:Makoto Nitta、Tomoshige Kobayashi
DOI:10.1246/cl.1986.463
日期:1986.4.5
phenylphosphorane, conveniently prepared from α-azidostyrene and triphenylphosphine, readily undergoes an annelation reaction with tropone derivatives to result in the formation of 1-azaazulene ringsystem.
Diels–Alder Reaction of Tropones with Arynes: Synthesis of Functionalized Benzobicyclo[3.2.2]nonatrienones
作者:Manikandan Thangaraj、Sachin Suresh Bhojgude、Rajesh H. Bisht、Rajesh G. Gonnade、Akkattu T. Biju
DOI:10.1021/jo500819w
日期:2014.5.16
A new procedure for the mild, practical, and scalable Diels–Alder reaction of tropones with arynes is reported. Differently substituted tropones undergo selective [4 + 2] cycloaddition with arynes generated in situ by the fluoride-induced 1,2-elimination of 2-(trimethylsilyl)aryl triflates, allowing the formation of functionalized benzobicyclo[3.2.2]nonatrienone derivatives in moderate to good yields
The reactions of α-chloro-, α-bromo-, α-methoxy-, and α-hydroxy-tropones and N-trichloroacetyltroponimine with dehydrobenzene are described.
描述了α-氯代-,α-溴代-,α-甲氧基-和α-羟基肌醇与N-三氯乙酰基肌醇与脱氢苯的反应。
Lewis Acid Catalyzed Inverse-Electron-Demand Diels−Alder Reaction of Tropones
作者:Pingfan Li、Hisashi Yamamoto
DOI:10.1021/ja908127f
日期:2009.11.25
Lewisacidcatalyzed inverse-electron-demand Diels-Alderreaction of tropone derivatives was developed. Up to 97% ee was obtained for the chiral dinucleus BINOL-aluminum complex catalyzedreaction between tropones and ketene diethyl acetal to give bicyclo[3.2.2] ring structures, which opens up a unique way of making chiral seven-membered rings.