Studies an Acetylenic Compounds. XXIII. A New Ring Closure of 2-Propynyl Ethers
作者:Issei Iwai、Junya Ide
DOI:10.1248/cpb.10.926
日期:——
It has been reported that 2-naphthyl allylic ethers undergo the Claisen rearrangement to give naphthol derivatives. 2-naphthyl propargyl ether derivatives, _??_-O·CH2C≡C-R (R=H, CH3, Ph.), replacing the double bond of allylic ethers by a triple bond, do not undergo the Claisen rearrangement but a new ring-closure to give 3H-naphtho [2, 1-b] pyran derivatives. Moreover, 1-naphthyl derivatives, _??_O·CH2C≡C-Phalso undergo the same ring-closure to give 4-phenyl-2H-naphtho [1, 2-b] pyran. The structures of new pyran derivatives obtained by the new ring-closure were confirmed by the melting point, infrared and ultraviolet spectra of the authentic samples which were synthesized by another routes.
据报道,2-萘基烯丙基醚通过克莱森重排生成萘酚衍生物。2-萘基丙炔醚衍生物_??_-O-CH2C≡C-R(R=H、CH3、Ph.)以三键取代烯丙基醚的双键,不会发生克莱森重排,而是发生新的环闭反应,得到 3H-萘并[2,1-b]吡喃衍生物。此外,1-萘基衍生物_??_O-CH2C≡C-Phalso 也会发生同样的闭环反应,生成 4-苯基-2H-萘并 [1, 2-b] 吡喃。通过新的闭环反应得到的新吡喃衍生物的结构,由另一种路线合成的真实样品的熔点、红外线和紫外线光谱得到了证实。