Behaviors of α-Fluorocarbenoids Derived from the Nucleophilic Desulfinylation of α-Chloro-α-fluoroalkyl Sulfoxides
作者:Hidemitsu Uno、Katsuji Sakamoto、Fumihiko Semba、Hitomi Suzuki
DOI:10.1246/bcsj.65.210
日期:1992.1
2-Aryl-1-chloro-1-fluoroethyl sulfoxides underwent nucleophilic desulfinylation with PhMgBr to give (Z)-fluorostyrene derivatives in a very stereoselective manner (> 33 : 1) via an α-fluorocarbene species. When treated with 3 equiv of PhLi in the presence of N,N,N′,N′-tetramethylethylenediamine, they similarly formed fluorostyrenes as a stereoisomeric mixture (E : Z = 2 : 1), but with 1 equiv of PhLi 2-aryl-1-chloro-1-fluoroethanes were the major product. On the other hand, no formation of a fluoroalkene was observed in the desulfinylation of 1-chloro-1-fluoro-4-phenylbutyl sulfoxide with the nucleophiles. In the latter reaction, oxidation and/or phenylation of the intermediate carbene were the main pathways.
2-芳基-1-氯-1-氟乙基亚砜与PhMgBr发生亲核去亚砜反应,以非常立体选择性的方式(> 33:1)生成(Z)氟苯乙烯衍生物,通过一个α-氟碳烯物种。当与3等物的PhLi在N,N,N′,N′-四甲基乙烯二胺存在下处理时,它们同样生成了氟苯乙烯的立体异构体混合物(E:Z = 2:1),但在1等物的PhLi下,2-芳基-1-氯-1-氟乙烷是主要产物。另一方面,在1-氯-1-氟-4-苯基丁基亚砜的去亚砜反应中,没有观察到氟烯烃的形成。在后者反应中,中间碳烯的氧化和/或苯基化是主要途径。