Studies on Grignard reagents. Part I. Fluorine nuclear magnetic resonance spectra of fluoroaryl Grignard reagents
作者:D. F. Evans、M. S. Khan
DOI:10.1039/j19670001643
日期:——
1·0; C6F5MgCl, 2·0; C6F5Mgl, 1·4; 3-F,5,4Cl2C6H2·MgBr, ca. 2·5; C10H6FMgl, 20; p-F·C6H4·MgBr, 20; p-F·C6H4·Mgl 20. Limited additional information concerning the nature of these “RMgX” and “R2Mg” species has been obtained from the fluorine chemical shifts. The rates of fluoroaryl exchange qualitatively follow the sequence C6F5Mgl < C6F5MgBr < C6F5MgCl C10H6FMgl < C6H2Cl2FMgBr < p-F·C6H4·Mgl < p-F·C6H4·MgBr
已在一定温度范围内测量了氟代芳基格氏试剂,相应的双芳基镁以及两者的混合物的氟共振光谱。因此,有可能减慢氟芳基交换并明确区分“ RMgX”和“ R 2 Mg”物质。纯格氏试剂在乙醚溶液中的比率2 [“ RMgX”] / [“ R 2 Mg”]的值是:C 6 F 5 MgBr,1·0;C 6 F 5 MgBr,1·0。C 6 F 5 MgCl,2·0; m / z。C 6 F 5 Mgl,1·4;C 6 F 5 Mgl,1·4。3-F,5,4Cl 2 C 6 H 2 ·MgBr,约。2·5; C 10 H 6 FMgl,20; p -F·C 6 H 4 ·MgBr,20;p -F·C 6 H 4 ·Mgl 20.关于这些“ RMgX”和“ R 2 Mg”物质的性质的有限的附加信息已从氟化学位移获得。氟芳基交换速率定性地遵循以下顺序:C 6 F 5 Mgl