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

作者：Meng, Jiang; Wen, Min; Zhang, Shiwei; Pan, Peiwen; Yu, Xingxin^*; Deng, Wei-Ping^*

来源：Journal of Organic Chemistry, 2017, 82(3): 1676-1687.

DOI：10.1021/acs.joc.6b02846

• AMINO-ACID-DERIVATIVES
• C-SP3-H BOND ADJACENT
• EFFICIENT SYNTHESIS
• TRANSITION-METAL
• SUBSTITUTED 1,2,4-TRIAZINES
• CATALYZED SYNTHESIS
• AZOMETHINE YLIDES
• 3+2 CYCLOADDITION
• NITROGEN ATOM
• RAPID ACCESS

A practical and efficient method for divergent synthesis of 3,6-disubstituted- and 3,S,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.

• 出版日期2017-2-3
• 单位华东理工大学