Beckmann Rearrangement of 4,5,6-Trisubstituted 3-Acetylpyridin-2-one Oximes
摘要:
Beckmann rearrangement of 4,5,6-trisubstituted 3-acetylpyridin-2-one oximes took place, involving equilibrium between the methyl-syn and -anti forms, to give exclusively 4,5,6-trisubstituted 3-acetylaminopyridin-2-ones in satisfactory yields.
A Versatile New Method for Synthesis of Isoquinolines; 6,8-Dihydroxyisoquinoline Derivatives from 6-Methyl-1,3-oxazin-4-ones
作者:Yutaka Yamamoto、Yasuo Morita、Osamu Ohmukai
DOI:10.3987/com-91-s75
日期:——
A versatile method for synthesis of isoquinolone derivatives (4a-h) from 2-substituted 6-methyl-4H-1,3-oxazin-4-ones (1a-h) is described. Transformation of 1a-h with diethyl acetonedicarboxylate (2) in the presence of potassium tert-butoxide afforded 6-substituted 3-acetyl-5-ethoxycarbonyl-4-ethoxycarbonylmethylene-2-pyridones (3a-h) in excellent yields. Dieckmann-type cyclization of 3a-h with sodium ethoxide in ethanol produced the corresponding isoquinolone derivatives (4a-h) in good yields, respectively.