2,3-dicyano-5,6-dichloro-p-benzoquinone in chloroform 2 h; Inert atmosphere;

1.1: sodium hydroxide / dichloromethane; water / 20 °C / Inert atmosphere 2.1: N,N,N',N,-tetramethylethylenediamine; sec.-butyllithium / cyclohexane; diethyl ether / 2 h / -78 °C / Inert atmosphere 2.2: -78 - 20 °C / Inert atmosphere 3.1: N-bromosuccinmide / dichloromethane / 20 °C / Inert atmosphere 3.3: 20 °C 4.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / chloroform / 2 h / Inert atmosphere View Scheme

1.1: N,N,N',N,-tetramethylethylenediamine; sec.-butyllithium / cyclohexane; diethyl ether / 2 h / -78 °C / Inert atmosphere 1.2: -78 - 20 °C / Inert atmosphere 2.1: N-bromosuccinmide / dichloromethane / 20 °C / Inert atmosphere 2.3: 20 °C 3.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / chloroform / 2 h / Inert atmosphere View Scheme

1.1: N-bromosuccinmide / dichloromethane / 20 °C / Inert atmosphere 1.3: 20 °C 2.1: 2,3-dicyano-5,6-dichloro-p-benzoquinone / chloroform / 2 h / Inert atmosphere View Scheme