Synthesis via 2-Acylmethyl-2-oxazoline. I. A Novel Synthesis of 3-Acyl-2-pyridones by Michael Addition of 2-Acylmethyl-2-oxazoline to<i>α</i>,<i>β</i>-Acetylenic Ketones
作者:Yasuo Tohda、Takeshi Yanagidani、Shin-ichi Hiramatsu、Nagatoshi Nishiwaki、Keita Tani、Kazuko Imagawa、Masahiro Ariga
DOI:10.1246/bcsj.70.2781
日期:1997.11
The reaction of the sodium salt of 2-acylmethyl-4,4-dimethyl-2-oxazolines with α,β-acetylenic ketones in ethanol gave Michael adducts, which were easily transformed to 4,6-disubstituted 3-acyl-1-(2-hydroxy-1,1-dimethylethyl)-2-pyridones by silica gel. N-Dealkylation of the pyridones was performed using hydrochloric acid in good yields. Deacylation of the pyridones was performed using potassium hydroxide
2-酰基甲基-4,4-二甲基-2-恶唑啉的钠盐与α,β-炔酮在乙醇中反应生成迈克尔加合物,该加合物很容易转化为4,6-二取代的3-酰基-1-( 2-羟基-1,1-二甲基乙基)-2-吡啶酮通过硅胶。使用盐酸以良好的收率进行吡啶酮的 N-脱烷基化。使用氢氧化钾进行吡啶酮的脱酰化。用碱或硅胶对吡啶酮进行温和处理,通过分子内迈克尔加成得到 7-oxa-1-azabicyclo[4.3.0]non-3-en-2-one 衍生物。2-苯甲酰基-2-恶唑啉与二苯丙酮的类似反应得到相应的 1-(2-羟乙基)-2-吡啶酮衍生物,其对这些 1-脱烷基化、3-脱酰基化和分子内加成反应呈惰性。