Combined Directed Metalation – Suzuki-Miyaura Cross Coupling Strategies. Synthesis of Isomeric Chromenopyridinones and Related Annulated Analogues
作者:Victor Snieckus、Ricarda E. Miller、Roman Sommer、Hope Fan、Ulrich Groth
DOI:10.3987/com-12-s(n)131
日期:——
A general strategy encompassing a Directed ortho Metalation (DoM) - Suzuki-Miyaura cross coupling and Directed remote Metalation (DreM) sequence for the synthesis of 5H-chromeno[4,3-c]pyridin-5-ones 5a-j, 5H-chromeno[3,4-b]pyridin-5-ones 6a-j, 5H-chromeno[3,4-c]pyridin-5-ones 13a-d, 12H-benzo[7,8]chromenopyridin-12-ones 16a-c, 17a-c, and pyrido[31,41:4,5]pyrano[2,3-e]indazol-5(111)-one analogues 18, 28 is reported. Thus, using the powerful directed metalation group properties of aryl O-carbamates 9a-h, 14a-c metalation-boronation followed by Suzuki-Miyaura coupling with 3-bromopyridine affords a variety of azabiaryls 7a-i, 8a-b, 12a-c, 15a-c which, upon DreM reaction leads to several series of chromenopyridinones 5a-j, 6a-j, 13a-d and pyridonaphthopyrones 16a-c, 17a-c. The synthesis of an unusual pyridopyranoindazolone 18 is also described.