S<sub>N</sub>2 Reactions in Dipolar Aprotic Solvents. Chlorine Isotopic Exchange Reactions of 2-Arylethyl Chlorides, Chloromethyl Aryl Ethers, and Chloromethyl Aryl Sulfides in Acetonitrile
作者:Jun-ichi Hayami、Nobuo Tanaka、Syuji Kurabayashi、Yasuhiro Kotani、Aritsune Kaji
DOI:10.1246/bcsj.44.3091
日期:1971.11
The SN2 reactions having a symmetrical transition state were studied in a dipolar aprotic solvent. A good Hammett correlation was found for the chlorine isotopic exchange reactions in acetonitrile between tetraethylammonium chloride and three types of substituted methyl chlorides, 2-arylethyl chlorides, chloromethyl aryl ethers, and chloromethyl aryl sulfides. The reaction constant was positive for
在偶极非质子溶剂中研究了具有对称过渡态的 SN2 反应。发现四乙基氯化铵与三类取代甲基氯、2-芳基乙基氯、氯甲基芳基醚和氯甲基芳基硫化物在乙腈中的氯同位素交换反应具有良好的哈米特相关性。2-芳基乙基氯的反应常数为正,具有α-杂原子的甲基氯的反应常数为负。反应中心 α 位上氧和硫原子的存在导致速率分别提高约 105 倍和 103 倍。讨论了这些 SN2 反应的过渡态特征。