7463-28-7Relevant articles and documents
Increasing the Activity of Copper Guanidine Quinoline Catalysts: Substitution at the Quinoline Backbone Leads to Highly Active Complexes for ATRP
Kr?ckert, Konstantin W.,Mannsperger, Johannes S.,R?sener, Thomas,Hoffmann, Alexander,Herres-Pawlis, Sonja
supporting information, p. 832 - 842 (2021/03/31)
Copper bromide complexes with the ligands TMG6NO2qu, TMG6Brqu, TMG6Methoxyqu, TMG6NMe2qu, TMG6EHOqu and TMG6dBAqu were examined regarding their activity in atom transfer radical polymerization (ATRP). The ligands were inspired by 1,1,3,3-tetramethyl-2-(quinolin-8-yl)guanidine (TMGqu) and the substituents have been chosen with a large range between electron withdrawing and donating abilities. The donor properties of the ligands can be strongly influenced and further highly active catalysts based on these systems can be obtained. The ligands with strong donating moieties were in addition modified by alkyl groups to increase the solubility in apolar monomers like styrene. CuI and CuII bromide complexes were crystallised and the structural data correlated to the different substituents and the catalyst activity. The electrochemical potentials E1/2, the equilibrium constants KATRP and rate constants kact and kdeact were determined. Polymerizations of styrene were conducted in solution whereas the catalyst based on TMG6EHOqu shows a good solubility and performance in bulk.
Visible-light-induced Beckmann rearrangement by organic photoredox catalysis
Tang, Li,Wang, Zhi-Lv,Wan, Hai-Lan,He, Yan-Hong,Guan, Zhi
supporting information, p. 6182 - 6186 (2020/09/01)
A facile and general strategy for efficient direct conversion of oximes to amides using an inexpensive organic photocatalyst and visible light is described. This radical Beckmann rearrangement can be performed under mild conditions. Various alkyl aryl ketoximes and diaryl ketoximes can be effectively converted into the corresponding amides in excellent yields.
An Electrochemical Beckmann Rearrangement: Traditional Reaction via Modern Radical Mechanism
Tang, Li,Wang, Zhi-Lv,He, Yan-Hong,Guan, Zhi
, p. 4929 - 4936 (2020/08/21)
Abstract: Electrosynthesis as a potential means of introducing heteroatoms into the carbon framework is rarely studied. Herein, the electrochemical Beckmann rearrangement, i. e. the direct electrolysis of ketoximes to amides, is presented for the first time. Using a constant current as the driving force, the reaction can be easily carried out under neutral conditions at room temperature. Based on a series of mechanistic studies, a novel radical Beckmann rearrangement mechanism is proposed. This electrochemical Beckmann rearrangement does not follow the trans-migration rule of the classical Beckmann rearrangement.