Cycloaromatization of the thienyl tetrayne 1, which was prepared in several steps from bis(trimethylsilyl)butadiyne and 3-bromothiophene-2-carbaldehyde, in benzene (0.33 mM) in the presence of molecular sieves 3A at room temperature gave the indeno[2,1-b]thiophene ring-fused 1H-2-benzopyran derivative 10 and indeno[2,1-b]thiophene derivative 11 in 11 and 40% yields, respectively. In contrast, cycloaromatization of 1 in the presence of water molecules at room temperature gave the indeno[2,1-b]thiophene ring-fused 1H-2-benzopyran derivative 10 and the indene ring-fused indeno[2,1-b]thiophene derivative 12 in 82 and 14% yields, respectively. Cycloaromatization of the phenyl tetrayne 9 in the presence of water molecules at room temperature also resulted in a dramatic change in product yields.
噻吩基四炔 1 是由双(三甲基甲
硅烷基)
丁二炔和
3-溴噻吩-2-甲醛在苯(0.33 mM)中在
分子筛 3A 存在下在室温下通过几个步骤制备的环芳构化得到
茚[2, 1-b]
噻吩环稠合的1H-2-苯并
吡喃衍
生物10和
茚并[2,1-b]
噻吩衍
生物11的产率分别为11%和40%。相比之下,1在室温下在
水分子存在下环芳构化得到
茚并[2,1-b]
噻吩环稠合的1H-2-苯并
吡喃衍
生物10和
茚环稠合
茚并[2,1-b]
噻吩衍
生物12的产率分别为82%和14%。在室温下,在
水分子存在下,苯基四炔 9 的环芳构化也导致产物收率发生巨大变化。