1: 1.) (CH3)2SO4 / 1.) 14 h, r.t., 2.) 50percent aq. EtOH, 14 h, r.t. 2: 28 percent / diethyl ether; tetrahydrofuran / 14 h / Ambient temperature View Scheme

in tetrahydrofuran; diethyl ether 14 h; Ambient temperature;