Variations on the Blaise Reaction: Synthesis of 3,5-Dioxopentanoates and 3-Amino-5-oxopent-3-enoates

Synthesis, crystal structure, and Hirshfeld surface analysis of 3-ferrocenyl-1-(pyridin-2-yl)-1H-pyrazol-5-amine

A key step towards utilizing polynuclear metal-based systems in magnetic device applications involves the careful design of ligands. This strategic planning aims to produce metal assemblies that exhibit some kind of 'switch' mechanism. Towards this end, a ligand that incorporates a redox-active functional group (ferrocene) is reported. This communication presents the multi-step synthesis, characterization (1H and 13C NMR), and structural analysis (single-crystal X-ray diffraction and Hirshfeld surface analysis) of 3-ferrocenyl-1-(pyridin-2-yl)-1H-pyrazol-5-amine, [Fe(C5H5)(C13H11N4)]. Supra-molecular features, including π-π stacking and hydrogen bonding are qu-anti-fied, while a database search reveals the unique combination of mol-ecular moieties, which offer future opportunities for studies to involve simultaneous Lewis acid and base coordin-ation.

Enantioselective Fluorination of α-Branched β-Ynone Esters Using a Cinchona-Based Phase-Transfer Catalyst

Herein, we report the fluorination of α-branched β-ynone esters to afford their corresponding quaternary fluorinated products with good enantioselectivity (ee = 73-90%) using a cinchona-based phase-transfer catalyst. α-Branched β-ynone esters possess a highly acidic α-proton and form their corresponding enolate as a single isomer, which allows the enantioselective fluorination reaction to occur under standard cinchona-based phase-transfer catalyst conditions. Moreover, the obtained α-fluorinated product can be treated with [(SPhos)AuNTf₂] (1 mol %) to afford a fluorinated 3,5-diketo carboxylic acid.

Blaise reaction: synthesis, skeletal diversification of C(4) substituted 5-ylidenepyrrol-(5H)-ones and the role of the strategically located ester on the reactivity of the nitriles

We have achieved a simple and convenient synthesis of several C(4) substituted 5-ylidenepyrrol-(5H)-ones from 3-aryl/heteroaryl/alkyl 3-cyanopropionates and ethyl/methyl bromoacetates via a useful variation of the classical Blaise reaction.