Strong Base-Induced Cycloaddition Reaction of Homophthalic Anhydride with Aldehydes.
作者:Ryuichi OKUNAKA、Takao HONDA、Maiko KONDO、Yasumitsu TAMURA、Yasuyuki KITA
DOI:10.1248/cpb.39.1298
日期:——
The reaction of homophthalic anhydride (1) and aldehydes in the presence of a strong base was studied. Reaction of 1 and benzaldehyde in the presence of NaH in anhydrous tetrahydrofuran (THF) at low temperature (0°C-room temperature) followed by treatment with diazomethane gave the cycloadduct, trans-4-methoxycarbonyl-3-phenyl-3, 4-dihydrocoumarin, and the reaction at 50°C gave, after similar work-up, the C-4 methylene condensed product, methyl 2-(2-methoxycarbonylphenyl)-3-phenylacrylate, selectively. Treatment of homophthalic anhydride having a terminal aldehyde group in the side chain at the C-4 position with NaH in anhydrous THF at low temperature resulted in intramolecular cycloaddition in fair yield.
研究了高邻苯二甲酸酐(1)和醛在强碱存在下的反应。 1 和苯甲醛在 NaH 存在下,在无水四氢呋喃 (THF) 中,在低温(0°C-室温)下反应,然后用重氮甲烷处理,得到环加合物,反式-4-甲氧基羰基-3-苯基-3, 4-二氢香豆素,在50℃下反应,经过类似的处理后,选择性地得到C-4亚甲基缩合产物,2-(2-甲氧基羰基苯基)-3-苯基丙烯酸甲酯。在低温下用无水THF中的NaH处理在C-4位侧链上具有末端醛基的高邻苯二甲酸酐,导致分子内环加成反应,产率较高。