; Thermal reaction of alkynyl propargyl sulfides 1 in the presence of n-BuN 3 followed by moist silica gel treatment afforded 4-methylenecyclobutenones 4 in moderate yields. Photogeneration of allenylketenes 5 from 4 in the presence of amine or methanol gave 3,4-pentadienamides 6 or methyl 3,4-pentadienates 7, respectively. Similar reaction in the presence of aldimines afforded unsaturated δ-lactams
                                    ; 炔基炔丙基
硫化物 1 在 n-BuN 3 存在下进行热反应,然后进行湿
硅胶处理,以中等产率得到 4-亚甲基
环丁烯酮 4。在胺或
甲醇的存在下,从 4 光生成烯基烯酮 5 分别得到 3,4-
戊二烯酰胺 6 或 3,4-
戊二烯酸甲酯 7。在醛
亚胺存在下的类似反应以良好的产率得到不饱和 δ-内酰胺 9。