1.1: ozone / dichloromethane / 1 h / -70 °C 1.2: -70 - 20 °C / |Inert atmosphere 2.1: sodium hydrogencarbonate / dimethyl sulfoxide / 6 h / 150 °C / |Inert atmosphere 3.1: ozone / dichloromethane / 1.08 h / -78 °C 3.2: -78 - 20 °C / |Inert atmosphere 4.1: potassium tert-butylate / tert-butyl alcohol / 0.83 h / |Inert atmosphere; |Reflux 4.2: 1 h / |Inert atmosphere; |Reflux 5.1: copper(ll) bromide; lithium bromide / acetonitrile / 20 h / |Inert atmosphere; |Reflux View Scheme