78886-14-3Relevant academic research and scientific papers
The synthesis and analysis of lignin-bound Hibbert ketone structures in technical lignins
Miles-Barrett, Daniel M.,Neal, Andrew R.,Hand, Calum,Montgomery, James R.D.,Panovic, Isabella,Ojo, O. Stephen,Lancefield, Christopher S.,Cordes, David B.,Slawin, Alexandra M.Z.,Lebl, Tomas,Westwood, Nicholas J.
supporting information, p. 10023 - 10030 (2016/11/06)
Understanding the structure of technical lignins resulting from acid-catalysed treatment of lignocellulosic biomass is important for their future applications. Here we report an investigation into the fate of lignin under acidic aqueous organosolv conditions. In particular we examine in detail the formation and reactivity of non-native Hibbert ketone structures found in isolated organosolv lignins from both Douglas fir and beech woods. Through the use of model compounds combined with HSQC, HMBC and HSQC-TOCSY NMR experiments we demonstrate that, depending on the lignin source, both S and G lignin-bound Hibbert ketone units can be present. We also show that these units can serve as a source of novel mono-aromatic compounds following an additional lignin depolymerisation reaction.
Chemocontrolled reduction of α-keto esters by hydrides: A possible solution for selective reduction of the ester function
Dalla,Catteau
, p. 6497 - 6510 (2007/10/03)
α-keto primary alcohols or α-silyloxy ketones have been obtained with a high level of selectivity from enolic α-keto esters in two steps, with the reduction of the α-silyloxy α,β-unsaturated ester by LiAlH4 as the key step. The methodology developed in this work represents a 'reversed' chemoselective reduction of the ester group instead of the keto of an enolic α-keto ester due to a one-pot sequential ester reduction-desilylation or silyl migration process.
