Reactions of 1,3-Dihaloadamantanes with Carbanions in DMSO: Ring-Opening Reactions to Bicyclo[3.3.1]nonane Derivatives by the S<sub>RN</sub>1 Mechanism
作者:Andrés E. Lukach、Ana N. Santiago、Roberto A. Rossi
DOI:10.1021/jo9620728
日期:1997.6.1
The reactions of 1,3-dihaloadamantanes with various carbanionic nucleophiles were studied. Potassium enolates of acetophenone (2) and pinacolone (10b) and the anion of nitromethane (10a) reacted with 1,3-diiodoadamantane (1a) in DMSO under photostimulation by a free radical chain process to form a 1-iodo monosubstitution product as an intermediate, which undergoes concerted fragmentation to form derivatives
研究了1,3-二重金刚烷与各种碳原子亲核试剂的反应。苯乙酮(2)和频哪酮(10b)的烯醇钾和硝基甲烷(10a)的阴离子在光刺激下通过自由基链过程在DMSO中与1,3-二碘十二金刚烷(1a)反应形成1-碘单取代产物中间体,该中间体经历一致的断裂以形成7-亚甲基双环[3.3.1]壬烯的衍生物(3和11)。该反应在25摄氏度的黑暗环境中不会发生,对光刺激的反应会被对二硝基苯部分抑制。1,3-二溴金刚烷(1b)和1-溴-3-氯金刚烷(1c)在2的照射下也发生了反应,尽管比1a慢得多,但也得到了7-亚甲基双环[3.3.1]壬烯衍生物3。当使用不带酸性氢原子的亲核试剂(例如异丁苯酮(16)的烯醇离子)时,为了抑制金刚烷的开环,它在1a的照射下反应生成金刚烷产物1-碘金刚烷,单取代的17、1-碘单取代的19和二取代的20。它们的分布取决于实验条件。在这些反应中,1-碘金刚烷和19是中间体。对于涉及1-碘