Lawesson's reagent in tetrahydrofuran 2 h; Heating;

1: 88 percent / aqueous ammonia / 0.5 h / Ambient temperature 2: 66 percent / 2,4-bis(methoxyphenyl)-1,3-dithia-2,4-diphosphetane 2,4-disulfide (Lawesson's reagent) / tetrahydrofuran / 2 h / Heating View Scheme

in toluene 17 h; Heating;