Stereochemistry of the Reactions of Trimethylgermyl Anions with 4-<i>t</i>-Butylcyclohexyl Derivatives
作者:Kunio Mochida、Tsuyoshi Kugita
DOI:10.1246/bcsj.61.3727
日期:1988.10
The stereochemistry of trimethylgermyllithium, -sodium, and -potassium with cis- and trans-4-t-butylcyclohexyl bromides and trimethylstannanes was investigated by 1H NMR spectroscopy. With the 4-t-butylcyclohexyl derivatives trimethylgermyl anions gave mixtures of cis- and trans-4-t-butylcyclohexyltrimethylgermanes. These results confirmed that free-radical pathways are important in such reactions
通过 1 H NMR 光谱研究了三甲基锗基锂、-钠和-钾与顺-和反-4-叔丁基环己基溴化物和三甲基锡烷的立体化学。使用4-叔丁基环己基衍生物,三甲基锗基阴离子得到顺式和反式4-叔丁基环己基三甲基锗烷的混合物。这些结果证实自由基途径在此类反应中很重要。
We have developed a practical stereoretentive iodine/lithium‐exchange process that allows the stereodefined preparation of cis‐ and trans‐cycloalkyllithium compounds from their corresponding stereodefined iodides. Quenching with electrophiles offers stereospecific access to both cis‐ (up to 96 % cis) and trans‐cycloalkyl derivatives (up to 99 % trans). A detailed study of the thermodynamic stabilities