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
Rh-Catalyzed diastereoselective desymmetrization of enone tethered-cyclohexadienones <i>via</i> tandem arylative cyclization
作者:Sandip B. Jadhav、Satish B. Thopate、Jagadeesh Babu Nanubolu、Rambabu Chegondi
DOI:10.1039/c8ob02284d
日期:——
rhodium-catalyzed arylative cyclization of enone tethered-cyclohexadienones has been developed with high efficiency, thus providing cis-fused bicyclic enones in good yields and with excellent diastereoselectivities. Furthermore, this mild transformation has a broad range of substrate scope and excellent functional group tolerance. In addition, bicyclic products have an enone functionality, which can be
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
The cascade difunctionalization of α,β-unsaturated carbonyls by nucleophilic halogenation followed by enolate trapping with other electrophiles is highly challenging in synthetic organic chemistry. Herein, we report a chemo- and diastereoselective cascade annulation of enone-tethered cyclohexadienones by using an unconventional combined Lewisacidcatalyzed halogenation reaction in the presence of