Transition-metal-free synthesis of 4-amino isoquinolin-1(2H)-ones via a tandem reaction of arynes and oxazoles

Abstract

A facile and transition-metal-free method for the synthesis of 4-amino isoquinolin-1(2H)-ones has been developed. Arynes react with 4, 5-disubstituted oxazoles through a tandem Diels-Alder reaction/dehydrogenation-aromatization/tautamerization process to produce 4-amino isoquinolin-1(2H)-ones...

LiN(SiMe3)2/KOtBu-Promoted Synthesis of Isoquinolone Derivatives from 2-Methylaryl Aldehydes and Nitriles

“…On the basis of our experimental results and the literature, ,− a possible mechanism is proposed (Scheme ). The reaction commences with oxidation of 1a to give intermediate A .…”

“…Isoquinolones, as a type of the most common fused six-membered heterocycles, exhibit broad medicinal properties, including antitumor, antiobesity, antiviral, and other effects . In the past years, various synthetic methods for isoquinolones have been reported, including denitrogenative/decarbonylative alkyne insertion, carbonylation/decarboxylation, C–C bond activation of benzocyclobutenols, cyclocondensation of 2-alkylnyl benzaldehydes with primary amines, intramolecular annulation, isomerization of (diarylmethylidene)-3,4-dihydroisoquinolin-1­(2 H )-ones, Sonogashira coupling/Schmidt reaction, and Diels–Alder reaction of arynes with 4,5-disubstituted oxazoles followed by dehydrogenation–aromatization/tautomerization . However, most of the starting materials in these methods are not commercially available, and thus, the substrate scope is generally limited.…”

An asymmetric metal-templated route to amino acids with an isoquinolone coreviaa Rh(iii)-catalyzed coupling of aryl hydroxamates with chiral propargylglycine Ni(ii) complexes

“…Among the different strategies to synthesize isoquinolones, 4,5 a Rh( iii )-catalyzed C–H activation/annulation of various readily available aryl hydroxamates with alkynes is one of the most efficient and straightforward approaches. 6,7 In particular, this reaction proved to be a key step in the total synthesis of natural products, such as rosettacin and nauclefine.…”

Advances in the synthesis of nitrogen-containing heterocyclic compounds byin situbenzyne cycloaddition

“…The reaction is easy to scale up, and the product can effectively convert into isoquinoline derivatives (Scheme 22c). 99…”