1.1: toluene-4-sulfonic acid / toluene / 24 h / |Dean-Stark; |Reflux 2.1: n-hexyl lithium / toluene; hexane / 0.5 h / -40 °C 2.2: 1.5 h / -40 - 0 °C 3.1: hydrogenchloride; acetic acid / water / 1 h / 20 °C 3.2: 0.5 h / |Reflux 3.3: 1.5 h / 20 °C View Scheme