Hypervalent Iodine(III)-Mediated Benzannulation of Enamines with Alkynes: an Efficient Synthesis of Substituted Aminonaphthoic Acid Derivatives

摘要: An intermolecular two CC bond formation procedure for the synthesis of carbocycles mediated by hypervalent iodine(III) reagents was developed. This metal free protocol provided a new approach useful substituted 1-amino-2-naphthoic acid derivatives via benzannulation reactions. Various N-unsubstituted and N-alkyl aromatic enamines with terminal alkynes non-terminal can be converted into corresponding under mild reaction conditions. When meta-substituted phenyl were employed in reaction, cyclization paths detected ortho-cyclization products only or major products. Good functional group tolerance, readily available material high atom utilization efficiency make this method potential which may find broad application organic synthesis.