The C-H Activation/Bidirecting Group Strategy for Selective Direct Synthesis of Diverse 1,1'-Biisoquinolines.

Multidentate ligands are highly important but difficult to access. Herein we disclose an atom- and step-economic synthesis of highly substituted 1,1'-biisoquinolines by a C-H activation/bididirecting group strategy. Through rational design of a bididirecting group to "N-OH + N-OAc", selective unsymmetrical diannulation with two different alkynes in a one-pot reaction has been achieved for the first time to access unsymmetrical biisoquinolines. Moreover, the resultant biisoquinolines show tunable photoluminescence and serve as aggregation-induced emission (AIE) systems.