Application of E1cB Elimination in Asymmetric Organocatalytic Cascade Reactions To Construct Polyheterocyclic Compounds
作者:Zhi-Hao You、Ying-Han Chen、Yu Tang、Yan-Kai Liu
DOI:10.1021/acs.orglett.9b03138
日期:2019.10.18
By introducing a carbon functionality at 2-position of chromane, the formal asymmetric functionalization of the 3-position of 2-substituted chromane has been realized via a highly chemo-, regio-, and stereoselective organocatalyticcascadereaction in a sequential one-pot manner involving an E1cB mechanism governed ring-opening process. Critical to our success was the design of a chiral dipeptide-based
Organophosphine bearing multiple hydrogen-bond donors for asymmetric Michael addition reaction of 1-oxoindane-2-carboxylic acid ester via dual-reagent catalysis
phosphines derived from dipeptide dual-reagents catalyzed asymmetric Michael addition reactions between indene esters and activated olefins in high yields and good to excellent enantioselectivities under mild reaction conditions. The success of current highly selective reactions should provide inspiration for expansion to other reactions and would open up new paradigms for the synthesis of indanone derivatives
A TMG catalyzed, practical and efficient hydrophosphorylation of 4-oxo-enoates by diethyl or diphenyl phosphite has been described. This protocol allows a convenient access to a variety of enol phosphates under mild conditions in good yield with excellent stereoselectivity.
Cooperative Heterobimetallic Zinc/Alkaline Earth Metal Catalysis: A Zn/Sr Aminophenol Sulfonamide Complex for Catalytic Asymmetric Michael Addition of 3-Acetoxy-2-oxindoles to β-Ester Enones
A heterobimetallic zinc/strontium catalyst has been developed for the asymmetric Michael addition of 3-acetoxy-2-oxindoles to β-ester enones in high yields with excellent enantioselectivities and high diastereoselectivities. This process represents that 3-acetoxy-2-oxindoles can be used as a stable air- and base-tolerant precursor for chiral 3-substituted 3-hydroxy-2-oxindoles.