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Syntheses, characterizations and thermal analyses of four novel unsymmetrical β-diketiminates
Siddappa A Patil1, Phillip A Medina, Joseph W Ziller
1Department of Chemistry & Science of Advanced Materials Program, Central Michigan University, Mount Pleasant, MI 48859 USA.
Abstract:
Four novel unsymmetrical β-diketiminates 2-(2,6-diisopropylphenyl)amino-4-(phenyl)imino-2-pentene (4a), 2-(2,6-diisopropylphenyl)amino-4-(4-methylphenyl)imino-2-pentene (4b), 2-(2,6-diisopropylphenyl)amino-4-(4-methoxyphenyl)imino-2-pentene (4c) and 2-(2,6-diisopropylphenyl)amino-4-(4-chlorophenyl)imino-2-pentene (4d) were synthesized with a 77-84% yield, and were characterized by spectroscopic methods ((1)H NMR, (13)C NMR, IR and mass spectrometry), elemental analysis, and X-ray single-crystal diffraction, respectively. Spectroscopic and X-ray single-crystal diffraction analyses determined the structures of the four β-diketiminates. While thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) showed two distinct endothermic peaks for each β-diketiminate at temperatures of 92.55°C and 221.50°C (4a), 93.51°C and 238.82°C (4b), 109.60°C and 329.22°C (4c), 115.43°C and 243.25°C (4d), respectively, corresponding to their melting and boiling points.
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