Synthesis of Alkyl 2-[2-oxopyridin-1(2H)-yl]acrylates by Nucleophilic Addition of Alkyl Propiolates Catalysed by Ph3P

A Mild and Highly Diastereoselective Preparation of N-Alkenyl-2-Pyridones via 2-Halopyridinium Salts and Aldehydes

An experimentally simple one-pot preparation of N-alkenyl-2-pyridones is reported. The reaction features mild conditions using readily available 2-halopyridinium salts and aldehydes. N-Alkenyl-2-pyridone formation proceeds with high diastereoselectivity, and a wide range of aldehyde reaction partners is tolerated. Pyridone products are also amenable to further manipulation, including conversion to N-alkyl pyridones and polycyclic ring systems.

Synthesis of Densely Functionalized N-Alkenyl 2-Pyridones via Benzyne-Induced Ring Opening of Thiazolino-Fused 2-Pyridones

We report the synthesis of 6-arylthio-substituted-N-alkenyl 2-pyridones by ring opening of bicyclic thiazolino-2-pyridones with arynes. Varied functionalization was used to investigate scope and substituent influences on reactivity. Selected conditions favor thioether ring opening over [4 + 2] cycloaddition and an unusual aryne incorporating ring expansion. Deuterium labeling was used to clarify observed reactivity. Using the knowledge, we produced drug-like molecules with complex substitution patterns and show how thioether ring opening can be used on scaffolds with competing reactivities.

A One-Pot Synthesis of Functionalised 1-Azadienes Containing 2-Thioxoimidazolidin-4-Ones

The zwitterionic 1:1 intermediates generated by addition of alkyl isocyanides to acetylenic esters are trapped by 3-methyl-5,5-diaryl-2-thioxoimidazolidin-4-ones to yield dialkyl 2-[(alkylimino)(3-methyl-4-oxo-5,5-diaryl-2-thioxoimidazolidin-1-yl)methyl]but-2-enedioates in good yields.

Efficient and regioselective synthesis of bicyclic pyrrolidones or bicyclic pyridones by cyclocondensation of heterocyclic ketene aminals with nitro-phenylpropiolate

HKAs underwent nucleophilic addition to the α, β-unsaturated CC of nitro-phenylpropiolate, obtaining a series of novel bicyclic pyrrolidones or bicyclic pyridones, whereas the opposite regioselectivity was observed.

Synthesis of a new class of β-iodo N-alkenyl 2-pyridones

A new method for the synthesis of β-iodo N-alkenyl 2-pyridones from substituted 2-propargyloxypyridines has been discovered . These compounds present a unique complement of orthogonal functionality and structural characteristics that are unavailable via other routes. The ready access to these compounds renders them an important entry point for the preparation of more complex N-alkyl pyridone-containing targets.

Solvent-Free Synthesis of 1,2,3,4-Tetrasubstituted Pyrroles from Enaminones and β-Nitrostyrenes

A simple synthesis of 1,2,3,4-tetrasubstituted pyrrole derivatives from the reaction of enaminones with β-nitrosty-renes, under solvent-free conditions, is described.

An Efficient One-Pot Synthesis of Trialkyl 2-(Dialkoxyphosphoryl)Ethene-1,1,2-Tricarboxylates

An efficient synthesis of trialkyl 2-(dialkoxyphosphoryl)ethene-1,1,2-tricarboxylates is described. This involves the reaction of alkyl cyanoformates, dialkyl acetylenedicarboxylates, and trialkyl phosphites.