RMN Carbons

Both the cited hidrognios are ' ' trocveis' ' in the hydrogen linkings, what it justifies the singletos. In composites that possess the group metoxila, one is verified singleto in d 3,60, referring to the three methylic hidrognios, strong ' ' desblindados' ' for the atom of present oxygen. If the oxygen of this group (metoxila) will be changed by one carbonila (C =), the electron-attractive effect of carbonlico carbon (lesser of what of the oxygen) will contribute for the one sprouting singleto in d 2,00. (This ' ' troca' ' it increased the electronic density on the cited hidrognios, then the chemical displacement diminished). In relation to the Nuclear Magnetic Carbon Resonance (RMN 13C), carbon atoms sp3 absorb in d 0,00 50,00 and carbons sp2 in d 100,00 the 150,00. The specter can be gotten ' ' with or sem' ' hydrogen coupling (1H? prtio). In the first case, methylic carbons (CH3) have its signal unfolded in quarteto, while the metilnicos carbon signal (CH2) is seen as tripleto.

The metnicos carbon atoms (CH) are seen as dubleto and the hidrogenados carbons (c) do not appear with the signal type singleto, in the specter. Carbon atoms 12C do not possess magnetic moment, for in such a way do not produce RMN specters. The RMN specter 13C of the benzene shows one dubleto centered in d 130. In this example, the carbon atoms are mono-hidrogenados (CH, metnicos), what it unfolds the signal in dubleto. As these carbons they are olefnicos (carbons sp2) its signal inside meets of band d 100,00 the 150,00. Carbons of carbonila of ketones appear as singleto in d 200, while of carbonila of aldehydes (group aldoxila) they are identified, in the specter, as dubleto centered in d 190. In esters, carbon atom of the group carbonila (C =) absorbs in d 160-170 ppm. In acid carboxlicos, the carbon of the group carboxila (COOH) absorbs in d 180 ppm.