A new and efficient approach to isoxazolines. First synthesis of 3-aryl-5-dichloromethyl-2-isoxazolines

作者：Guirado Antonio^*; Martiz Bruno; Andreu Raquel; Bautista Delia

来源：Tetrahedron, 2011, 67(32): 5811-5815.

DOI：10.1016/j.tet.2011.05.110

• Isoxazolines
• Chloral
• Acetophenones
• Enones
• Oximes

An efficient synthetic method for 3-aryl-5-dichloromethyl-2-isoxazolines has been established. Reactions between anhydrous chloral and acetophenones in hot acetic acid lead to 1-aryl-4,4,4-trichloro-3-hydroxybutan-1-ones (chloralacetophenones), which provided 1-aryl-4,4-dichlorobut-3-en-1-ones (2,2-dichlorovinylacetophenones) by dehydration and subsequent electrochemical reduction. These beta,gamma-unsaturated enones reacted with hydroxylamine yielding oxime intermediates whose treatment with aqueous sodium hydroxide gave novel 3-aryl-5-dichloromethyl-2-isoxazolines in fair to high yields. The molecular structure of a member of this family of compounds, 5-dichoromethyl-3-(4-methoxyphenyl)-2-isoxazoline, was determined by X-ray crystallography.

• 出版日期2011-8-12