B. V. Pinto, A. G. Ferreira, E. Cavalheiro
Mar 21, 2017
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Influential Citations
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Journal
Journal of Thermal Analysis and Calorimetry
Abstract
Thermal behavior of fluoxetine hydrochloride ((±)-N-methyl-3-phenyl-3-[4-(trifluoromethyl)phenoxy]propan-1-amine), an antidepressant of the selective serotonin reuptake inhibitor family, has been investigated using thermoanalytical techniques and evolved gas analysis performed with thermogravimetry coupled to Fourier transform infrared spectroscopy (TG-FTIR) and intermediate residue analysis by GC–MS. In inert atmosphere, the decomposition took place as two mass loss events with residue of 0.13% at the end of the run. In air atmosphere, decomposition occurred in three steps, the last one as a result of the oxidative burning of the carbonaceous matter. DTA and DSC curves demonstrated that sample melts at 159.6 °C (∆Hfus = 37.4 kJ mol−1) without recrystallization on cooling. Hot-stage microscopy data corroborate these observations. TG-FTIR studies revealed that fluoxetine decomposes after melting, releasing 4-trifluoromethylphenol, methylamine. GC–MS analysis of the solid resulting from heating the fluoxetine hydrochloride up to 230 °C revealed the presence of the original sample and 4-trifluoromethylphenol as the main residue. Based on these results, a mechanism for fluoxetine thermal decomposition was proposed.