6967-45-9Relevant articles and documents
Amine-Mediated Bond Cleavage in Oxidized Lignin Models
Li, Hongji,Liu, Meijiang,Liu, Huifang,Luo, Nengchao,Zhang, Chaofeng,Wang, Feng
, p. 4660 - 4665 (2020/07/04)
Introducing amines/ammonia into lignin cracking will allow novel bond cleavage pathways. Herein, a method of amines/ammonia-mediated bond cleavage in oxidized lignin β-O-4 models was studied using a copper catalyst at room temperature, demonstrating the effect of the amine source on the selectivity of products. For primary and secondary aliphatic amines, lignin ketone models underwent oxidative Cα?Cβ bond cleavage and Cα?N bond formation to generate aromatic amides. For ammonia, the competition between oxygen and ammonia determined the selectivity between Cα?N and Cβ?N bond formation, generating amides and α-keto amides, respectively. For tertiary amines, the lignin models underwent oxidative Cα?Cβ bond cleavage to benzoic acids. Control experiments indicated that amines act as nucleophiles attacking at the Cα or Cβ position of the oxidized β-O-4 linkage to be cleaved. This study represents a novel example that the breakage of oxidized lignin model can be regulated by amines with a copper catalyst.
Oxidative amidation of benzaldehydes and benzylamines with: N -substituted formamides over a Co/Al hydrotalcite-derived catalyst
Gupta, Shyam Sunder R.,Nakhate, Akhil V.,Rasal, Kalidas B.,Deshmukh, Gunjan P.,Mannepalli, Lakshmi Kantam
, p. 15268 - 15276 (2017/12/15)
The present work describes a highly efficient synthetic strategy for amides via oxidative coupling of benzaldehydes or benzylamines with N-substituted formamides using a heterogeneous Co/Al hydrotalcite-derived catalyst in the presence of TBHP. A series of Co/Al hydrotalcite-derived catalysts (Cat-2, Cat-3, and Cat-4 with the Co2+/Al3+ molar ratio in the synthesis mixture as 1/1, 2/1 and 3/1) have been prepared by a simple co-precipitation method and characterized using powder XRD, XPS, FEG-SEM, EDS, FT-IR, DTG-TGA and N2 physical adsorption techniques. Among the as-prepared catalysts, Cat-3 exhibited excellent catalytic activity towards the direct amidation of benzaldehydes as well as benzylamines bearing various substituents into the corresponding amides at 100 °C using TBHP as an oxidant. The mechanistic investigation of the amidation reaction revealed that the reaction follows a radical pathway. Furthermore, the catalyst is easily separable and recyclable without considerable loss in catalytic activity.
A 3,4-dimethoxy-N, N method for preparing-dimethyl-benzamide
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Paragraph 0024-0025, (2017/02/24)
The invention provides a new preparation method of 3,4-dimethoxy-N,N-dimethylbenzamide. 1,2-dimethoxybenzene, which is relative low in cost, is employed as a raw material in the method and is subjected to a reaction, catalyzed by anhydrous aluminium chloride, with N,N-dimethylaminoformyl chloride. An aimed product (II) is prepared through post-process. The preparation method is low in production cost, is simple and safe in operation and has an industrial production value.
