ChemInform Abstract: Gold‐Catalyzed Oxidative Cyclization of 1,5‐Enynes Using External Oxidants.

Abstract

Gold-Catalyzed Oxidative Cyclization of 1,5-Enynes Using External Oxidants. -Gold-catalyzed oxidative cyclization of o-(aminoalkynyl)styrenes (I) and (III) in the presence of methylquinoline N-oxide provides access towards indenecarboxamides (II) and (IV) via oxidation of the alkynyl C-2 carbon. In contrast, terminal alkynes like in o-ethynylstyrenes (VI) and (X) are selectively oxidized at the alkynyl C-1 carbon atom to give, after double cyclization process, cyclopropano-fused indan derivatives (VII) and (XI). This reaction cascade proceeds stereospecifically. -(VASU, D.; HUNG, H.-H.; BHUNIA, S.; GAWADE, S. A.; DAS, A.; LIU*, R.-S.; Angew. Chem., Int. Ed. 50 (2011) 30, 6911-6914, http://dx.doi.org/10.1002/anie.201102581 ; Dep. Chem., Natl. Tsing Hua Univ., Hsinchu 30013, Taiwan; Eng.) -Mischke