Amino proton

Figure B2.4.3. Proton NMR spectrum of the aldehyde proton in N-labelled fonnainide. This proton has couplings of 1.76 Hz and 13.55 Hz to the two amino protons, and a couplmg of 15.0 Hz to the nucleus. The outer lines in die spectrum remain sharp, since they represent the sum of the couplings, which is unaffected by the exchange. The iimer lines of the multiplet broaden and coalesce, as in figure B2.4.1. The other peaks in the 303 K spectrum are due to the NH2 protons, whose chemical shifts are even more temperature dependent than that of the aldehyde proton.

Quinoline, 6-amino-protonation, 2, 341 Quinoline, 7-amino-protonation, 2, 341 Quinoline, 8-amino-alkylation, 2, 179 methylation, 2, 342 Quinoline, 4-amino-7-chloro-as antimalarial, 2, 517 Quinoline, 2-amino-3-cyanotetrahydro-synthesis... 

Later, Taft and his coworkers examined the H-bonding donor ability of the amino protons in 4-nitroaniline and 4-nitrophenol as the hydrogen bond donors. They also tried... 

Variation of the X-substituent in (190) may be used to tune the pH at which efficient extraction occurs. For example, for the case where X = N02, the electron-withdrawing ability of this group results in more facile deprotonation of the amino proton. Thus the extraction may be performed at a lower pH than for the system with X = H. Similarly, variation of n in (190) may be used to tune the system for metal ions of different radii. 

Figure 19 illustrates the decoupling of the two adjacent amino protons H2 and H 3 in Cu(gly)240). The spectral changes of the high-frequency doublet of proton H2 are observed while the transition of proton H3 within the same ms-state is pumped with the frequency v2 = cK(ms) and various B2ff(B2) field strengths. 

Figure 38 shows the angular dependence of the ENDOR transitions of the amino protons in Cu(II)-doped TGS for B0 normal to a m The observed eight-line pattern... 

Fig. 38. Angular dependence of the amino proton ENDOR signals of TGS doped with Cu(II) ions. Rotation axis along a. (Adapted from Ref. 188)...

The improved pulse sequence was applied to correlate the signals of each of the quaternary carbons of compound 2 with the resonances of the the closely spaced methyl and amino protons. The resulting connections of chemical shifts served to overcome ambiguities left in the... 

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