DIKETENE AS A 3-BUTENOIC ACID SYNTHON IN TRANSITION METAL-CATALYZED ALKYLATION OF A TRIMETHYLSILYLMETHYL GRIGNARD REAGENT
作者:Kenji Itoh、Toshinobu Yogo、Yoshio Ishii
DOI:10.1246/cl.1977.103
日期:1977.2.5
The reaction of (CH3)3SiCH2MgCl with diketene yields 3-trimethylsilylmethyl-3-butenoic acid (1) in the presence of a catalytic amount of NiCl2(95%), PdCl2(68%), CoCl3(60%), or CuI(20%) under moderate conditions. The acid, 1, is isomerized to the conjugated acid, 4-trimethylsilyl-3-methyl-2-butenoic acid (2) by means of an excess LiN(SiMe3)2. The rearrangement proceeds stereoselectively to 2-(E) isomer by addition of diglyme or N,N,N′,N′-tetramethylethylenediamine. This is the first example of the vinyl-oxygen bond cleavage of diketene.
在一定量的 NiCl2(95%)、PdCl2(68%)、CoCl3(60%)或 CuI(20%)催化下,(CH3)3SiCH2MgCl 与二乙烯反应生成 3-三甲基硅甲基-3-丁烯酸(1)。通过过量的 LiN(SiMe3)2,酸 1 异构化为共轭酸 4-三甲基硅基-3-甲基-2-丁烯酸 (2)。通过加入二甘氨酸或 N,N,N′,N′-四甲基乙二胺,重排可立体选择性地生成 2-(E)异构体。这是二酮烯乙烯氧键裂解的第一个实例。