An Efficient Procedure for the Preparation of (<i>E</i>)-α-Alkylidenecycloalkanones Mediated by a CeCl<sub>3</sub>·7H<sub>2</sub>O−NaI System. Novel Methodology for the Synthesis of (<i>S</i>)-(−)-Pulegone<sup>1</sup>
作者:Giuseppe Bartoli、Marcella Bosco、Renato Dalpozzo、Arianna Giuliani、Enrico Marcantoni、Tiziana Mecozzi、Letizia Sambri、Elisabetta Torregiani
DOI:10.1021/jo026418s
日期:2002.12.1
synthons used as the key intermediates in many important syntheses. Because of their potential, a general method of preparation from readily available starting materials, under very mild conditions, was considered to be worthwhile. Cerium(III) chloride heptahydrate in combination with sodium iodide in refluxing acetonitrile promotes a regio- and stereoselective beta-elimination reaction to (E)-2-alky
2-亚烷基环烷酮是强大的合成子,在许多重要合成中用作关键中间体。由于它们的潜力,人们认为在非常温和的条件下用容易获得的起始原料进行制备的一般方法是值得的。七水合氯化铈(III)与碘化钠在回流的乙腈中促进2-和(1-羟烷基)环烷酮中的(E)-2-亚烷基环烷酮的区域和立体选择性β消除反应。本方法的合成值通过光学活性形式的单萜(S)-(-)-普勒高酮(8)的合成来证明。