Dual Role of Anthranils as Amination and Transient Directing Group Sources: Synthesis of 2-Acyl Acridines
作者:Saegun Kim、Sang Hoon Han、Neeraj Kumar Mishra、Rina Chun、Young Hoon Jung、Hyung Sik Kim、Jung Su Park、In Su Kim
DOI:10.1021/acs.orglett.8b01571
日期:2018.7.6
The transient directing group promoted C(sp2)–H functionalization of benzaldehydes with anthranils by a cationic rhodium(III) catalyst is described. Notably, anthranils have been used as both transient directing groups and amination sources to afford 2-acyl acridines through direct C–H amination followed by acid-mediated cyclization. A range of substrate scopes and functional group tolerance were observed
of anthranils (III) led to ring enlargement with the formation of 3-acyl-2-methoxy-3H-azepines (IV). The reaction in ether containing water or amines yielded the corresponding 2-oxo- or 2-amino-3H-azepines (V or VII). On the other hand, photolysis of some 7-substituted 3-phenylanthranils (IX and XIII) gave the corresponding 9-acridanone derivatives (X and XIV). A hypothetical scheme (anthranil → nitrene