Integral editor mestrenova
The carboxylic acid substituent is moderately deactivating, drawing electron density away from the conjugated ð system at the ortho (C9) and para (C7) positions via the inductive effect, causing the C9 proton to shift downfield to 8.12 ppm while the C7 proton appears centered at 7.66 ppm. Dissimilar phenyl ring substituents cause ring proton chemical shifts to be dispersed between 7.0-8.2 ppm.
#Integral editor mestrenova series#
Aromatic protons appear as a series of multiplets. Signal broadening suggests a moderate rate of dynamic proton exchange of the labile proton. Carboxylic acids exist as stable hydrogen-bound dimers in non-polar solvents and these strongly deshielded protons typically appear between 11-12 ppm. The carboxylic acid resonance (O=COH) is identified by a characteristic downfield chemical shift at 11.77 ppm. The 1H NMR spectrum of a 4% (w/w 330 mM) solution of aspirin in chloroform-D was measured at 82 MHz using the Thermo Scientific picoSpin 80 NMR spectrometer.Īspirin contains aliphatic, aromatic and carboxylic acid protons that span a wide range of the 1H spectrum, and signal integration reveals a 3:4:1 intensity distribution, respectively. It is also used in low doses in preventive treatment against heart attacks, strokes and blood clots. Aspirin (C 9H 8O 4), acetylsalicylic acid, is a salicylate drug used to treat a variety of conditions, including headaches, fever and inflammation.