Application of E1cB Elimination in Asymmetric Organocatalytic Cascade Reactions To Construct Polyheterocyclic
Zhi-Hao You1, Ying-Han Chen1, Yu Tang1,2
1Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy , Ocean University of China , Qingdao 266003 , China.
Abstract:
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 organocatalytic cascade reaction 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 bifunctional acid-base organocatalyst, which exhibited high catalytic activity at low catalyst loading (1-0.1 mol %), leading to biologically interesting polyheterocyclic compounds.
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