19048-85-2Relevant articles and documents
N-Aroylbenzotriazoles as Efficient Reagents for o-Aroylation in Absence of Organic Solvent
Hahnvajanawong, Viwat,Phungpis, Baramee
, p. 2671 - 2674 (2021/10/25)
N-Aroylbenzotriazoles have been shown to be efficient reagents for esterification in the absence of organic solvent. Grinding of N-aroylbenzoytiazoles with twofold excess of alcohols for a couple of hours at room temperature gave corresponding esters in high percentage of yields.
N-Heterocyclic Carbene Catalyzed Ester Synthesis from Organic Halides through Incorporation of Oxygen Atoms from Air
Tan, Hui,Wang, Shen-An,Yan, Zixi,Liu, Jianzhong,Wei, Jialiang,Song, Song,Jiao, Ning
supporting information, p. 2140 - 2144 (2020/12/01)
Oxygenation reactions with molecular oxygen (O2) as the oxygen source provides a green and straightforward strategy for the construction of O-containing compounds. Demonstrated here is a novel N-heterocyclic carbene (NHC) catalyzed oxidative transformation of simple and readily available organic halides into valuable esters through the incorporation of O-atoms from O2. Mechanistic studies prove that the deoxy Breslow intermediate generated in situ is oxidized to a Breslow intermediate for further transformation by this oxidative protocol. This method broadens the field of NHC catalysis and promotes oxygenation reactions with O2.
Synthesis of Unsymmetrical N-Heterocyclic Carbene-Nitrogen-Phosphine Chelated Ruthenium(II) Complexes and Their Reactivity in Acceptorless Dehydrogenative Coupling of Alcohols to Esters
He, Xiaochun,Li, Yaqiu,Fu, Haiyan,Zheng, Xueli,Chen, Hua,Li, Ruixiang,Yu, Xiaojun
, p. 1750 - 1760 (2019/04/17)
Two novel ruthenium complexes RuH(CO)Cl(PPh3)(κ2-CP) (1) and [fac-RuH(CO)(PPh3)(κ3-CNP)]Cl (2) bearing unsymmetrical N-heterocyclic carbene-nitrogen-phosphine (CNP) were synthesized and characterized with 1H NMR, 31P NMR, and HRMS. The structure of complex 2 was further confirmed by single-crystal X-ray diffraction. An anion exchange experiment proved that complex 2 could transform into complex 1 in solution. The two complexes exhibited a highly catalytic performance in acceptorless dehydrogenative coupling of alcohols to esters, and the excellent isolated yields of esters were given in a catalyst loading of 1% for para- and meta-substituted benzyl alcohols and long-chain primary alcohols. Although some ortho-substituted benzyl alcohols displayed a relatively low reactivity due to the steric hindrance and the coordination of electron donor with the ruthenium center, the good product yields were still obtained by prolonging the reaction time. Especially, this system successfully realized the dehydrogenative cross-coupling to esters between two different primary alcohols.