1.1: lithium carbonate; lithium bromide / N,N-dimethyl-formamide / 3 h / 110 - 115 °C / |Inert atmosphere 2.1: ozone / methanol / 6 h / -40 - -30 °C / |Inert atmosphere; |Large scale 3.1: sodium hydroxide / ethanol; water / 8 - 9 °C / |Inert atmosphere 3.2: 1 h / 5 - 7 °C 3.3: 8.75 h / 1 - 9 °C View Scheme

Li2CO3; acetic acid; lithium bromide in n-heptane; water; ethyl acetate; N,N-dimethyl-formamide