Synthesis of 7-Aminocoumarins from 7-Hydroxycoumarins via Amide Smiles Rearrangement

Abstract

N-Substituted 7-aminocoumarins can be synthesized from readily available 7-hydroxycoumarins via alkylation with α-bromoacetamides and subsequent tandem O → N Smiles rearrangement–amide hydrolysis. The key rearrangement sequence proceeds under mild conditions to provide convenient access to various N -alkyl and N -aryl products in moderate to high yields. The process is operationally simple, inexpensive, transition-metal-free, and can be telescoped into a one-pot process.

Sunlight-driven photoinitiating systems for photopolymerization and application in direct laser writing

“…The N -substituted 7-aminocoumarin R11 could be readily synthesized from R10 by a tandem O → N Smiles rearrangement-hydrolysis reaction using cesium carbonate as the base. 34 R11 was obtained in 41% yield (see Scheme 1). Finally, B1 was obtained by alkylation of the secondary amine of R11 with iodohexane, using sodium hydride as the base.…”

Efficient Extraction in High-Acidity HNO3 Solution for Selective Separation of Am3+ Over Eu3+ by Amine-Diamide Ligands

“…To investigate the effects of substituents on the extraction ability and selectivity, five DAMIA ligands ( L I – L V ) with diverse substituent groups were synthesized following the synthesis routes shown in Scheme with reference to the reported literature. − Full details of the synthesis steps and characterization are given in the Supporting Information.…”

Recent Research Progress in Fluorescent Probes for Detection of Amyloid-β In Vivo

“…It is often used in the preparation of blue fluorescent peptides and other biomolecules [41]. Compared with some traditional fluorophores, coumarins are widely used in optical imaging because of their high fluorescence quantum yield, tunable photophysical and photochemical properties, and good stability [42,43].…”