<scp>Three‐Component</scp> Synthesis of <scp>2‐Heteroaryl</scp>‐3‐hydroxybenzo[<i>b</i>]‐thiophenes under <scp>Transition‐Metal‐Free</scp> Conditions
Dahan Wang, Fuhong Xiao, Feng Zhang, Guo‐Jun Deng
Abstract
Main observation and conclusion A convenient synthetic route to 2‐heteroaryl‐3‐hydroxybenzo[ b ]thiophene derivatives via K 2 CO 3 ‐promoted multicomponent cyclization between o ‐halogenated benzaldehyde, 2‐methylquinolines and sulfur powder has been demonstrated. This reaction is performed smoothly under simple conditions to give the corresponding products in moderate to good yields. The resultant 3‐hydroxybenzo[ b ]thiophenes have been proved to be versatile building blocks in a range of transition‐metal‐catalyzed cross‐coupling reactions.
Topics & Concepts
ChemistryBenzaldehydeThiopheneTransition metalCatalysisSulfurReaction conditionsCombinatorial chemistryComponent (thermodynamics)Coupling reactionStereochemistryOrganic chemistryPhysicsThermodynamicsSulfur-Based Synthesis TechniquesCatalytic C–H Functionalization MethodsMulticomponent Synthesis of Heterocycles