SINGLE STEP ENANTIOSELECTIVE PROCESS FOR THE PREPARATION OF 3-SUBSTITUTED CHIRAL PHTHALIDES
申请人:Council of Scientific & Industrial Research
公开号:US20140330027A1
公开(公告)日:2014-11-06
The present invention discloses single step, highly enantioselective catalytic oxidative cyclization process for the synthesis of 3-substituted chiral phthalides. In particular, the invention discloses asymmetric synthesis of chiral phthalides via synergetic nitrile accelerated oxidative cyclization of o-cyano substituted aryl alkenes in high yield and enantiomeric excess (ee) in short reaction time. Also, disclosed herein is “one-pot” asymmetric synthesis of biologically important natural compounds having 3-substituted chiral phthalide structural framework in the molecule.
[EN] A SINGLE STEP ENANTIOSELECTIVE PROCESS FOR THE PREPARATION OF 3-SUBSTITUTED CHIRAL PHTHALIDES<br/>[FR] PROCÉDÉ ÉNANTIOSÉLECTIF EN UNE SEULE ÉTAPE POUR LA PRÉPARATION DE PHTALIDES CHIRAUX 3-SUBSTITUÉS
申请人:COUNCIL SCIENT IND RES
公开号:WO2013072830A9
公开(公告)日:2014-02-20
A Series of Two Oxidation Reactions of <i>ortho</i>-Alkenylbenzamide with Hypervalent Iodine(III): A Concise Entry into (3<i>R</i>,4<i>R</i>)-4-Hydroxymellein and (3<i>R</i>,4<i>R</i>)-4-Hydroxy-6-methoxymellein
A sequence of oxidation reactions of alkenamides with hypervalent iodine is described. Oxidation of ortho-alkenylbenzamide substrates selectively gave isochroman-1-imine products. The products underwent further oxidation in the presence of a Pd salt catalyst leading to regioselective C-H acetoxylation at the 8-position. A series of oxidations was applied to the crucial steps of asymmetric synthesis of 4-hydroxymellein derivatives.
Enantiodifferentiating endo-Selective Oxylactonization of ortho-Alk-1-enylbenzoate with a Lactate-Derived Aryl-λ3-Iodane