Mechanism of the Reaction of Methoxycarbonylcarbene as Revealed by CIDNP. V. Thermal Reaction of Methyl Diazoacetate with Benzyl Ethers
作者:Hiizu Iwamura、Yuzo Imahashi、Katsuhiko Kushida、Kiyoshi Aoki、Shiroh Satoh
DOI:10.1246/bcsj.49.1690
日期:1976.6
demonstrates the formation of 3 by the cage recombination of radical pairs ‾PhCH2··CH(OR)CO2CH3 (2). Product analyses by VPC have also been performed and escape products toluene and ROCH2CO2CH3 (4) inherent to the radical pairs were detected. In the reaction with benzyl ethyl ether, 4 (R=PhCH2) without noticeable CIDNP is produced about six times more than 4 (R=CH3CH2). No methyl α-benzyloxybutyrate
当重氮乙酸甲酯与二苄基、苄基苯基和苄基乙基醚发生热反应时,会发生插入苄基碳-氧键的过程,分别生成PhCH2CH(OR)CO2CH3(3, R=PhCH2, Ph, and CH3CH2) )。在反应混合物的 1H 和 13C NMR 光谱中观察到由于插入产物 3 引起的强极化信号。Kaptein 规则对 CIDNP 信号的应用表明,通过自由基对 ‾PhCH2··CH(OR)CO2CH3 (2) 的笼式重组形成了 3。还进行了 VPC 产品分析,并检测到自由基对固有的逸出产物甲苯和 ROCH2CO2CH3 (4)。在与苄基乙醚的反应中,4 (R=PhCH2) 没有明显的 CIDNP 产生大约是 4 (R=CH3CH2) 的六倍。没有形成α-苄氧基丁酸甲酯。结果表明乙基比苄基更容易通过非自由基路径裂解。叶立德中间体 (PhCH2)R\overset⊕O–\overset\ominusCHC 的形成