Synthesis, Reactivity, and Application as Chiral Auxiliaries of the novel (3<i>R</i>)- and (3<i>S</i>)-4,5-dihydro-3-hydroxy-4,4,5,5-tetramethyl-3-phenylfuran-2(3<i>H</i>)-ones in the<i>Paterno</i>-<i>Büchi</i>reaction
作者:Thomas Oppenländer、Peter Schönholzer
DOI:10.1002/hlca.19890720815
日期:1989.12.13
of derivatives ((3′S)- and (3′RS)-5, (S)- and (±)-7, (±)-8, (±)-9) was accomplished by deprotonation with BuLi at room temperature and subsequent quenching of the Li alcoholate with acyl chlorides or acid anhydrides, demonstrating the extraordinary chemical stability of 3. Additionally, the course of the temperature-dependent diastereoselective Paterno-Büchi reaction of 2,3-dimethylbut-2-ene to the benzoylformate
新型α-羟基-γ-内酯(±)-3的两种对映体(4,5-二氢-3-羟基-4,4,5,5-四甲基-3-苯基呋喃-2(3 H)-one)通过水解由酮1和2,3-二甲基丁-2-烯的光化学[2 + 2]环加成而得的氧杂环丁烷2进行合成(Paterno - Büchi反应),涉及传统的非对映异构体的分离(方案2和3) 。(R)-和(S)-3的绝对构型( - ) - (1和相应的氧杂环丁烷的前体可能的X射线结构分析的基础上被分配小号,4 - [R )-莰烷酰衍生物(3'小号) - 5(的小号) - 3。Ö的酰化(小号) -和(±) - 3,得到多种衍生物((3'的小号) -和(3' RS) - 5,(小号) -和(±) - 7,(±) - 8,(±) - 9)是通过在室温下用BuLi进行质子化并随后用酰氯或酸酐将Li醇化物淬灭来完成的,证明了3的出色化学稳定性。另外,该依赖于温度的非对映选择性的过程帕特诺-步琪2