Enantioselective Synthesis of Hydrobenzofuranones Using an Asymmetric Desymmetrizing Intramolecular Stetter Reaction of Cyclohexadienones
作者:Qin Liu、Tomislav Rovis
DOI:10.1021/op600278f
日期:2007.5.1
A series of cyclohexadienones were synthesized by dearomatization of phenols followed by Dess-Martin oxidation. Asymmetric intramolecular Stetter reactions of these substrates provide hydrobenzofuranones in good to excellent yields and excellent stereoselectivities. Up to three stereocenters as well as quaternary stereocenter are formed from polysubstituted substrates. A scale up experiment demonstrates
Asymmetric Synthesis of Hydrobenzofuranones via Desymmetrization of Cyclohexadienones Using the Intramolecular Stetter Reaction
作者:Qin Liu、Tomislav Rovis
DOI:10.1021/ja058337u
日期:2006.3.1
Dearomatization of phenols followed by oxidation affords cyclohexadienyloxyacetaldehydes, which produce hydrobenzofuranones via asymmetric intramolecular Stetter reaction in good to excellent yield. Quaternary as well as up to three contiguous stereocenters may be formed in good to excellent enantioselectivities and high diastereoselectivities.
A modular approach has been developed for an efficient synthesis of an aminal group containing a new tetracyclic framework. The strategy has been devised based on selective hydrogen-bond-guided aza-Michael addition of heteroaromatic amines to cyclohexadienone-aldehydes. The reaction is highly atom economic and practical and involves stereoselective construction of four new C–N bonds and four rings
Asymmetric Intramolecular Oxa-Michael Reactions of Cyclohexadienones Catalyzed by a Primary Amine Salt
作者:Wenbin Wu、Xin Li、Huicai Huang、Xiaoqian Yuan、Junzhu Lu、Kailong Zhu、Jinxing Ye
DOI:10.1002/anie.201206977
日期:2013.2.4
Michael brings the rings: An asymmetricintramolecular oxa‐Michael reaction involving iminium activation has been developed. This reaction provides enantioenriched 1,4‐dioxane derivatives with up to 99 % yield and 98 % ee. The method allows for concise and stereoselective access to stereodiverse, complex tetracyclic compounds containing a bicyclo[2.2.2]octan‐2‐one backbone with multiple chiral centers
Catalyst-Controlled Diastereoselective Synthesis of Bridged [3.3.1] Bis(Indolyl)-Oxanes and Oxepanes via Desymmetrization of Bis(Indolyl)-Cyclohexadienones
oxepanes via diastereoselective desymmetrization of bis(indolyl)-cyclohexadienones is presented for the first time. The reaction is highly atom- and step-economic, furnishing sp3-rich functionalized bis(indolyl) derivatives in good to excellent yields with wide substrate scope. The reaction proceeds through Friedel–Crafts alkylation followed by catalyst-controlled selective C–Cbondformation/rearrangement