A modular CuI-L-proline catalyzed one-pot route for the rapid access of constrained and privileged hetero-atom-linked medium-sized ring systems

An efficient CuI-L-proline catalyzed one-pot synthesis was developed to generate a collection of skeletally diverse heterocyclic ring systems with sizes ranging from 6 to 9. A salient feature of this design strategy is its modular synthetic utility using an S_N2 reaction followed by a microwave assisted CuI-L-proline hetero-arylation, which has granted access to a series of heterocyclic frameworks including: benzoe]pyrrolo1,2-a]1,4]diazepin, benzoe]pyrrolo1,2-a]1,4]diazocin, benzoe]pyrido1,2-a]1,4]diazocinones, dibenzob,f]1,5]diazoninones, dihydrodibenzob,e]1,4]thiazepine, dibenzob,e]1,4]thiazocine and benzo6,7]1,4]diazepino1,2-a]indole. Moreover, the synthetic procedures described herein, allows rapid entries to synthetically challenging medium-sized heterocyclic systems with good overall yields.