535967-76-1Relevant academic research and scientific papers
Sequential Cleavage of Lignin Systems by Nitrogen Monoxide and Hydrazine
Altmann, Lisa-Marie,Heinrich, Markus R.,Hofmann, Dagmar,Hofmann, Laura Elena,Prusko, Lea
supporting information, (2020/03/27)
The cleavage of representative lignin systems has been achieved in a metal-free two-step sequence first employing nitrogen monoxide for oxidation followed by hydrazine for reductive C?O bond scission. In combining nitrogen monoxide and lignin, the newly developed valorization strategy shows the particular feature of starting from two waste materials, and it further exploits the attractive conditions of a Wolff-Kishner reduction for C?O bond cleavage for the first time. (Figure presented.).
One-pot synthesis of β-O-4 lignin models: Via the insertion of stable 2-diazo-1,3-dicarbonyls into O-H bonds
Burtoloso, Antonio C. B.,De Oliveira, Gabriela P.,Dias, Rafael Mafra P.
, p. 4815 - 4823 (2020/07/13)
Because lignin is a macromolecule that is a sustainable source of aromatic compounds, model substrates are commonly used to increase our understanding of its complex structure. However, few methods have been described for the synthesis of these models. Herein, we describe a new route towards the synthesis of β-O-4 lignin models by intermolecular O-H insertion reactions with simple and stable diazocarbonyls. The benefits of this developed method were shorter reaction times and high yields, as well as mild and environmentally friendly conditions. This journal is
A photochemical strategy for lignin degradation at room temperature
Nguyen, John D.,Matsuura, Bryan S.,Stephenson, Corey R. J.
supporting information, p. 1218 - 1221 (2014/02/14)
The development of a room-temperature lignin degradation strategy consisting of a chemoselective benzylic oxidation with a recyclable oxidant ([4-AcNH-TEMPO]BF4) and a catalytic reductive C-O bond cleavage utilizing the photocatalyst [Ir(ppy)2(dtbbpy)]PF6 is described. This system was tested on relevant lignin model substrates containing β-O-4 linkages to generate fragmentation products in good to excellent yields.
Chemoselective metal-free aerobic alcohol oxidation in lignin
Rahimi, Alireza,Azarpira, Ali,Kim, Hoon,Ralph, John,Stahl, Shannon S.
supporting information, p. 6415 - 6418 (2013/06/05)
An efficient organocatalytic method for chemoselective aerobic oxidation of secondary benzylic alcohols within lignin model compounds has been identified. Extension to selective oxidation in natural lignins has also been demonstrated. The optimal catalyst system consists of 4-acetamido-TEMPO (5 mol %; TEMPO = 2,2,6,6-tetramethylpiperidine-N-oxyl) in combination with HNO3 and HCl (10 mol % each). Preliminary studies highlight the prospect of combining this method with a subsequent oxidation step to achieve C-C bond cleavage.
