Double annulation of ortho- and peri-C–H bonds of fused (hetero)arenes to unusual oxepino-pyridines. Issue 39 (3rd June 2020)

• Record Type: Journal Article
• Authors: Shankar, Majji; Rit, Raja K.; Sau, Somratan; Mukherjee, Kallol; Gandon, Vincent; Sahoo, Akhila K.
• Is Part Of: Chemical science. Volume 11:Issue 39(2020)
• Page Start: 10770
• Page End: 10777
• Publication Date: 2020-06-03
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d0sc01373k
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : Direct difunctionalization of chemically distinct ortho - and peri -C–H bonds of fused hetero(arenes) is illustrated through an unusual one-pot domino {[4 + 2] & [5 + 2]} double annulation with alkynes for the first time. Abstract : Direct difunctionalization of chemically distinct ortho - and peri -C–H bonds of fused hetero(arenes) is illustrated through an unusual one-pot domino {[4 + 2] & [5 + 2]} double annulation with alkynes for the first time. This process is viable under Ru(ii )-catalysis using a sulfoximine directing group and builds four bonds [(C–C)–(C–N) and (C–C)–(C–O)] in a single operation. Such synthetic manifestation offers access to uncommon [6, 7]-fused oxepino-pyridine skeletons. DFT calculations provide mechanistic insight into this double annulation of naphthoic acid derivatives with alkynes and corroborate the participation of a ruthena-oxabicyclooctene intermediate, which is responsible for the rare 7-membered ring formation.