72278-09-2Relevant articles and documents
Monomeric Octahedral Ruthenium(II) Complex Enabled meta-C-H Nitration of Arenes with Removable Auxiliaries
Fan, Zhoulong,Li, Jie,Lu, Heng,Wang, Dong-Yu,Wang, Chao,Uchiyama, Masanobu,Zhang, Ao
supporting information, p. 3199 - 3202 (2017/06/23)
A removable oxime-assisted meta-C-H nitration of arenes is reported. Mechanistic investigations and DFT calculations reveal a new monomeric octahedral ruthenium(II) complex is responsible for the meta-selective nitration. Dioxygen as a cooxidant is crucial for achieving high conversion and good yields. Moreover, the utility of the present reaction protocol is further showcased by the late-stage modification of the clinical CNS drugs Diazepam and Fluvoxamine.
Meta-Selective CAr-H Nitration of Arenes through a Ru3(CO)12-Catalyzed Ortho-Metalation Strategy
Fan, Zhoulong,Ni, Jiabin,Zhang, Ao
supporting information, p. 8470 - 8475 (2016/07/26)
The first example of transition metal-catalyzed meta-selective CAr-H nitration of arenes is described. With the use of Ru3(CO)12 as the catalyst and Cu(NO3)2·3H2O as the nitro source, a wide spectrum of arenes bearing diversified N-heterocycles or oximido as the directing groups were nitrated with meta-selectivity exclusively. Mechanism studies have demonstrated the formation of a new 18e-octahedral ruthenium species as a key ortho-CAr-H metalated intermediate, which may be responsible for the subsequent meta-selective electrophilic aromatic substitution (SEAr). Moreover, this approach provides a fast-track strategy for atom/step economical synthesis of many useful pharmaceutical molecules.
