115997-63-2Relevant articles and documents
Iron-Mediated Cyclization of 1,3-Diynyl Propargyl Aryl Ethers with Dibutyl Diselenide: Synthesis of Selenophene-Fused Chromenes
Back, Davi F.,Lutz, Guilherme,Zeni, Gilson
, p. 1096 - 1105 (2020/01/25)
The synthesis of selenophene-fused chromene derivatives starting from 1,3-diynyl propargyl aryl ethers is reported herein. The method is based on carbon-carbon, carbon-selenium, selenium-carbon and carbon-selenium bonds formation in a one-pot protocol, using iron(III) chloride and dibutyl diselenide as promoters. The same reaction conditions were applied to propargyl anilines leading to the formation of 1-(butylselanyl)-selenophene quinolines. The results showed that the dilution and temperature of substrate addition had a crucial influence in the products obtained. When the substrates were added at room temperature, in the absence of a solvent, a mixture of products was obtained, whereas the slowly addition (15 min) of starting materials, as a dichloromethane solution, at 0 °C led to the product formation in good yields. The mechanistic study indicates that the cooperative action between iron(III) chloride and dibutyl diselenide was essential to promote the cyclization, whereas separately none of them was effective in promoting the cyclization. We proved the synthetic utility of heterocycles obtained in the Suzuki cross coupling reaction, giving the corresponding cross-coupled products in good yields. In addition, the organoselenium moiety was removed from the structures of products by using n-butyllithium. (Figure presented.).
THERMAL BEHAVIOUR OF ARYL γ-HALOPROPARGYL ETHERS
Ariamala, G.,Balasubramanian, K. K.
, p. 309 - 318 (2007/10/02)
A systematic study of the behaviour of aryl γ-halopropargyl ethers under thermal condition was undertaken.Aryl γ-bromopropargyl ethers 2 underwent unique transformation in N,N-diethylaniline (215 deg C, 6 h) giving rise to a mixture of products 3,4 and 5,whereas, under similar conditions aryl γ-chloropropargyl ethers 8, afforded 4-chlorochromenes, 9.A remarkable substituent and solvent effect has been observed in the thermolysis of these aryl γ-bromo and γ-chloropropargyl ethers, rendering this transformation as a method for the synthesis of a number of substituted 4-bromochromenes 3, 4-chlorochromenes 9 and chroman-4-ones 7.In contrast, solution thermolysis of aryl γ-iodopropargyl ether 11 afforded aryl propargyl ether 1 as the major product.
