6161-82-6Relevant academic research and scientific papers
Iridium-catalysed primary alcohol oxidation and hydrogen shuttling for the depolymerisation of lignin
Lancefield, Christopher S.,Teunissen, Lucas W.,Weckhuysen, Bert M.,Bruijnincx, Pieter C. A.
supporting information, p. 3214 - 3221 (2018/07/31)
Lignin is a potentially abundant renewable resource for the production of aromatic chemicals, however its selective depolymerisation is challenging. Here, we report a new catalytic system for the depolymerisation of lignin to novel, non-phenolic monoaromatic products based on the selective β-O-4 primary alcohol dehydrogenation with a Cp?Ir-bipyridonate catalyst complex under basic conditions. We show that this system is capable of promoting the depolymerisation of model compounds and isolated lignins via a sequence of selective primary alcohol dehydrogenation, retro-aldol (Cα-Cβ) bond cleavage and in situ stabilisation of the aldehyde products by transfer (de)hydrogenation to alcohols and carboxylic acids. This method was found to give good to excellent yields of cleavage products with both etherified and free-phenolic lignin model compounds and could be applied to real lignin to generate a range of novel non-phenolic monomers including diols and di-acids. We additionally show, by using the same catalyst in a convergent, one-pot procedure, that these products can be selectively channelled towards a single di-acid product, giving much simpler product mixtures as a result.
Molecular properties of the WB4101 enantiomers and of its chiral methyl derivatives for α1-adrenoceptor recognition
Villa,Valoti,Villa,Pallavicini,Ferri,Iuliano,Brunello
, p. 587 - 606 (2007/10/02)
The optical isomers of the well known α1-antagonist WB4101 and of its derivatives with a methyl group in the oxyethyl moiety were prepared for the evaluation of their α-adrenoceptors binding affinity. By means of a detailed computational analysis, the present work shows that the introduction of a methyl group affects the behaviour of WB4101 in different ways. A limitation of the conformational freedom in certain regions of the torsional subspace of the potential energy function, differences in the reactivity of the protonated species towards a model proton acceptor and the quality of the superposition with the rigid template for α1 antagonists, corynanthine, are examined and discussed in order to select a candidate bioactive form and possible features which act as modulators of the recognition process at the α1-adrenoceptors.
