Flavonoids, 42.1 Anomalous Intramolecular Conjugate Addition: Synthesis of 2-Amino-2-benzyl-3(2H)-benzofuranone and Related Compounds
17 September 2002 (online)
An easy and convenient preparation of 2-amino-2-benzyl-3(2H)-benzofuranone and related compounds is described. The method utilizes the anomalous intramolecular conjugate addition of intermediate 2-amino-1-(2-hydroxyphenyl)-3-phenyl-2-propen-1-ones. 2-Benzyl-2-triphenylphosphoranylideneamino-3(2H)-benzofuranones by an analogous method are extremely unreactive and have limited synthetic applicability.