Year: 2020
Type: article
Abstract: Fatty amides are used in the manufacture of drugs, cosmetics, plastics, insecticides, etc. but the synthetic process involves fatty ester-derived fatty acid steps with economic and environmental consequences. Fatty esters (vegetable oils) are available in abundance and renewable but have not been used directly or cost effectively in the production of fatty amides. The fatty ester is usually first stripped to fatty acids resulting in a two-step instead of a single step synthesis which requires high temperatures (100 – 240°C), long reaction time (3 – 72 hours) and the use of catalyst. We had previously reported on a novel green method for the direct formation of fatty amides from a fatty ester. In the present study, the functionality and applicability of this green method is evaluated using a culinary and non-culinary oil namely peanut and castor oils. Each oil sample was hydrolyzed with NaOH in a non-aqueous medium and reacted in-situ with NH4Cl at 50°C in a reaction time of 60 minutes with no catalyst added. Conversions of 83 and 79% were recorded for the reactions of peanut and castor oils, respectively. The products of synthesis were characterized by Fourier-transform infrared spectroscopy (FT-IR) and various concentrations of product samples and two reference samples - erucamide and oleamide obtained from Sigma Aldrich - were subjected to Gas chromatography – Mass spectrometry (GC/MS) analysis. The qualitative GC-MS reports revealed the presence of 9-octadecenamide (oleamide) and hexadecanamide (palmitamide) at retention times of 27.76 and 23.90 minutes, respectively for all samples, including the reference. The predominant component of the second reference sample, erucamide, was found to be 13-docosenamide (erucamide) appearing at GC retention time of 32.58 minutes. The IR spectra of the products are strongly indicative of the presence of amides. The GC-MS analysis of the product samples confirms the formation of fatty amides. The detection of oleamide and erucamide in the reference samples and the detection of methyl ricinoleate at GC retention time of 26.573 minutes in the castor oil product sample validates the GC-MS analysis and confirms the functionality and applicability of this novel method of synthesis.
Institutions: Texas Southern University, Howard University, University of Jos
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W3006357811