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.
Visible-Light-Mediated Facile Reductive Aromatization of Quinols
作者:Leifeng Wang、Zhiming Yan
DOI:10.1055/s-0035-1561404
日期:——
range of phenols bearing multiple useful functionalities at their meta positions were prepared from the corresponding quinols under the cooperative effects of visible light irradiation, Ru(bpy)3Cl2 photosensitizer, Hunig’s base, LiBF4, and MeCN solvent. The process involves visible-light-enabled photocatalytic cleavage of C–O bond as the strategic event.
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
their asymmetric catalytic genre remains unattempted. Herein, we describe the judicious design of an organocatalyticenantioselective desymmetric double aza-Michael addition cascade to access a series of functionalized fused morpholines with excellent yields and diastereo- and enantioselectivities. A one-pot telescopic synthesis was demonstrated for a bridged triheterocyclic compound. In addition, scale-up