2H-環庚[b]呋喃-2-酮的合成及性質

The Synthesis and Properties of 2H-Cyclohepta [b] furan-2-one

10.6623/chem.1973001

楊寶旺(Paw-Wang Yang)；林隆清(Lung-Ching Lin)

化學

62年1期（1973 / 03 / 01）

1 - 6

繁體中文

本研究改良Seto法^1，使2-氯（艹卓）酮在不同條件下，分別與三種不同活性亞甲基化合物(active methylene compound)作用得三種3-取代-2H-環庚[b]跌喃-2-酮類。次將此等產物分別在不同條件下以不同的酸處理均得熔點72°C的黃色結晶，2H-環庚[b]呋喃-2-酮，由此獲知其較佳的合成條件。次將2H-環庚[b]呋喃-2-酮分別在中性及強酸性溶液中測定其紫外線吸收光譜及核磁共振譜間，並行3-位的氘在交換反應結果，證實了3-位親電性反應的可行性。

The base catalyzed reaction of 2-chlorotropone with ethyl acetoacetate, diethyl malonate and dimethyl malonate gave 3-acetyl, 3-ethoxy carbonyl and 3-methoxy carbonyl 2H-cyclohepta [b] furan-2-one, respectively. The products formed were found to undergo acid decomposition to yield yellow crystals 2H-cyclohepta [b] furan-2-one of m. p. 71.5~72°C. The most favorable condition for synthesis of 2H-cyclohepta [b] furan-2-one has been found to be an application of the sodium compound of dimethyl malonate to 2-cholrotropone in benzene followed by heating the resulted compound with polyphosphoric acid for 2 hr. The UV and NMR spectra of 2H-cyclohepta [b] furan- 2- one in neutral and strongly acidic solution, and deuteration showed that 2H-cyclohepta [b] furan-2-onc would easily undergo electro-philic substitutions at position 3.