Synthesis and reduction reactions of pyridones and 5-acyl-2-methoxypyridines

Abstract

A note on versions:The version presented here may differ from the published version or, version of record, if you wish to cite this item you are advised to consult the publisher's version. Please see the 'permanent WRAP url' above for details on accessing the published version and note that access may require a subscription.For more information, please contact the WRAP Team at: publications@warwick.ac.uk Graphical AbstractTo create your abstract, type over the instructions in the template box below. Fonts or abstract dimensions should not be changed or altered. Abstract-The synthesis of a series of pyridones, from their 2-hydroxypyridine or 2-methoxypyridine precursors, is described, along with studies into their reductions to saturated heterocycles. A number of 5-acylpyridones were prepared and were evaluated as substrates for asymmetric transfer hydrogenation prior to conversion to saturated heterocycles. The enantioselective reduction of 5-acetyl-1-benzylpyrimidine-2,4(1H,3H)-dione is also described. Synthesis and Reduction Reactions of Pyridones and 5-Acyl-2-Methoxypyridines

An Efficient Two‐Step Preparation of α‐, β‐, γ‐ or δ‐Amino Acids from 2‐Pyrazinones, 2‐Hydroxypyrimidines or 2‐Pyridones Respectively

“…Similar results were obtained by reacting 1‐benzyl‐5‐(hydroxymethyl)pyridine‐2‐one with Pd/barium sulfate in methanol and under high pressure of hydrogen. The C–O cleaved product is isolated in 71 % yield . Our procedure is simple, general and does not require special apparatus, or harsh conditions.…”

“…The C-O cleaved product is isolated in 71 % yield. [21] Our procedure is simple, general and does not require special apparatus, or harsh conditions. The workup is easy, requiring only filtration of catalyst followed by removal of the solvent.…”

Recent Developments in Asymmetric Hydrogenation and Transfer Hydrogenation of Ketones and Imines through Dynamic Kinetic Resolution

“…The ATH of N-benzyl-5-acetyluracil was investigated by Wills and co-workers with the ruthenium catalysts (R,R)-CAT12 and (S,S)-CAT12 in HCO 2 H/Et 3 N (5:2) (Scheme 36). 59 Interestingly, the use of catalyst (R,R)-CAT12 resulted in the formation of the reduced compound in a 4:1 diastereomeric ratio (the relative configuration of the diastereomers was not determined) in 92% and 33% ee, respectively, whilst catalyst (S,S)-CAT12 gave similar results in terms of stereoselectivity delivering the same major diastereomer. These results suggest that conjugate addition occurred first, resulting in the formation of an enol intermediate, which would tautomerize to give a racemic ketone whose reduction may then proceed via a (dynamic)kinetic resolution.…”