Divergent synthesis of polysubstituted isoxazoles, isoxazoline N-oxides, and dihydroisoxazoles by a one-pot cascade reaction
Özet
An efficient one-pot synthesis of a new class of 3,4,5-trisubstituted isoxazoline N-oxides/isoxazoles and dihydroisoxazoles is developed by a green approach from aromatic and aliphatic aldehydes by controlling the reaction conditions. Aldehydes were reacted with ethyl nitroacetate in the presence of DABCO as a catalyst under ultrasonication. In aromatic aldehydes, isoxazoline N-oxides were obtained exclusively when the reaction was carried out at 40 degrees C, but raising the temperature to 80 degrees C isoxazoles were formed selectively. Aliphatic aldehydes, on the other hand, gave a mixture of isoxazoline N-oxides and dihydroisoxazoles where the ratio of these depended on the bulk of the aliphatic chain on the aldehyde. This is the first method for the synthesis of aliphatic 4-substituted-3,5-bis(ethoxycarbonyl)isoxazoline N-oxides and 4-substituted-3,5-bis(ethoxycarbonyl)-dihydroisoxazoles with good to excellent yields. (C) 2016 Elsevier Ltd. All rights reserved.
Anahtar kelimeler
Atıf için künye
ROUF, A., Şahin, E., & TANYELİ, C. (2017). Divergent synthesis of polysubstituted isoxazoles, isoxazoline N-oxides, and dihydroisoxazoles by a one-pot cascade reaction. TETRAHEDRON, 73(4), 331–337. https://doi.org/10.1016/j.tet.2016.12.005
BibTeX
@article{rouf2017-66653,
author = {ROUF, Abdul and Şahin, Ertan and TANYELİ, CİHANGİR},
title = {Divergent synthesis of polysubstituted isoxazoles, isoxazoline N-oxides, and dihydroisoxazoles by a one-pot cascade reaction},
journal = {TETRAHEDRON},
year = {2017},
volume = {73},
number = {4},
pages = {331--337},
issn = {0040-4020},
doi = {10.1016/j.tet.2016.12.005},
url = {https://akademik.atauni.edu.tr/yayinlar/66653-divergent-synthesis-of-polysubstituted-isoxazoles-isoxazoline-n-oxides-and}
}