Synthesis of Isoxazolines and Isoxazoles Inspired by Fipronil

Abstract

Phenylpyrazoles (or arylpyrazoles) are known to be extremely potent as noncompetitive inhibitors of the GABA-gated chloride channel on the GABA receptor. This project involves the synthesis of novel isoxazole and isoxazoline heterocycles that have similar structural features to the commercially used phenylpyrazole, fipronil. Synthesis of the appropriately substituted styrenes and phenylacetylenes is followed by 1,3-dipolar cycloaddition reaction with several aliphatic nitrile oxides, which are prepared in situ from aldoximes with bleach. Relative reaction rates were determined for these specialized alkene and alkyne dipolarophiles.

Calcium Carbide: From Elemental Carbon to Isotope‐Economic Synthesis of 13C2‐Labeled Heterocycles†

“…A slow transformation oxime – chlorooxime – nitrile oxide allows to avoid side processes including undesired nitrile oxide transformation to furoxan, which is possible for non‐aromatic nitrile oxides. [ 84 ] Using this procedure, 4d was synthesized in 75% yield.…”

Amidoxime-Containing Zr and Hf Atomic Layer Deposition Precursors for Metal Oxide Thin Films

“…It was initially believed that the amidoxime ligands play a key role in satisfying the coordination site of the metal with the M–O–N oxime –C–N amide ring system when the anionic form of the ligand forms a bond with the cationic metal through the dative bond from N amide to the metal as shown in Figure a. Two amidoxime ligands, mdaoH and tdaoH, were synthesized according to previously reported procedures , with the purpose of comparing the structural differences of their metal complexes depending on the substituents such as methyl groups and tert -butyl groups on the carbon in the amidoxime backbone.…”

“…The tdaoH and mdaoH ligands were prepared according to a previously reported method. , Almost all chemicals were purchased from Aldrich and TCI and used as received without further purification prior to use. Tris­(dimethylamido)­cyclopentadienyl zirconium [CpZr­(NMe 2 ) 3 ] and hafnium [CpHf­(NMe 2 ) 3 ] were purchased from DNF and HUMIST.…”