title: Unexpected O-H Insertion of Rhodium-Azavinylcarbenes with N-Acylhydrazones: Divergent Synthesis of 3,6-Disubstituted- and 3,5,6-Trisubstituted-1,2,4-Triazines.
abstract: A practical and efficient method for divergent synthesis of 3,6-disubstituted- and 3,5,6-trisubstituted-1,2,4-triazines via unexpected rhodium-catalyzed O-H insertion/rearrangement/conditions-controlled intramolecular cyclization and oxidation reaction under mild conditions has been developed. Notably, it is the first example for the synthesis of 1,2,4-triazines with different substituted-patterns via a common intermediate with excellent chemoselectivities by the reaction of N-acylhydrazones as aze-[3C] or [4C] synthons with N-sulfonyl-1,2,3-triazoles as aze-[2C] synthons. Furthermore, this method allows direct access to di(het)aryl ketone frameworks containing 1,2,4-triazine moiety for the first time, serving as a versatile building block for the synthesis of other useful heterocyclic skeletons, such as pyridine or pyridazinone-fused triazine in excellent yields.
authors.affiliation: Shanghai Key Laboratory of New Drug Design & School of Pharmacy, East China University of Science and Technology , 130 Meilong Road, Shanghai 200237, China.
authors.forename: Jiang
authors.initials: J
authors.lastname: Meng
authors.affiliation: Shanghai Key Laboratory of New Drug Design & School of Pharmacy, East China University of Science and Technology , 130 Meilong Road, Shanghai 200237, China.
authors.forename: Min
authors.initials: M
authors.lastname: Wen
authors.affiliation: Shanghai Key Laboratory of New Drug Design & School of Pharmacy, East China University of Science and Technology , 130 Meilong Road, Shanghai 200237, China.
authors.forename: Shiwei
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Shanghai Key Laboratory of New Drug Design & School of Pharmacy, East China University of Science and Technology , 130 Meilong Road, Shanghai 200237, China.
authors.forename: Peiwen
authors.initials: P
authors.lastname: Pan
authors.affiliation: Shanghai Key Laboratory of New Drug Design & School of Pharmacy, East China University of Science and Technology , 130 Meilong Road, Shanghai 200237, China.
authors.forename: Xingxin
authors.identifier: 0000-0002-8370-2598
authors.initials: X
authors.lastname: Yu
authors.affiliation: Shanghai Key Laboratory of New Drug Design & School of Pharmacy, East China University of Science and Technology , 130 Meilong Road, Shanghai 200237, China.
authors.forename: Wei-Ping
authors.initials: WP
authors.lastname: Deng