1: 50 percent / pyridine / 4 h / Ambient temperature 2: 2.) hydrochloric acid / 1.) acetonitrile-DMA, 0.8 h, reflux, 2.) ether View Scheme

hydrogenchloride 1.) acetonitrile-DMA, 0.8 h, reflux, 2.) ether; Yield given. Multistep reaction;