Question

Label NMR spectra.

'H NMR Spectrum in CDCI; -2.289 L2.195 TTTTTTTTTTTTTTTTTTTTTTTTT 2.8 2.6 2.4 2.2 2.0 1.6 1.6 1.4 1.2 1.6 0.8 0.6 0.4 ppm 26.07 38.09 35.84

Label
Functional groups: Esters- ethyl acetate
# of unique H environment
local chemical environment
# of H in each environment
# of neighboring protons

Answer 1

» In H²_NMR number of of H-NMR number of signals depends on protons present in the molecule. ucture of Ethylacetate: the kinds → Structure es Hb Ha 11 H c-o- Ć - - Ha Hi ha s from the structure it es clear that ethylacetate has three differendt kinds of protons. Hence it have three signals in H² NMR spectra. • Splitting pattern of the signals depends upon the neighboring protons. splitting of signal follows. (n+1) rule. where, 'n' in no. of protons present the neighboring carbon. Identification of signals : - → The protons marked with a have a neighboring protons. Therefore splitting of signal = n+1 = 2+1 = 3( Triplet) The protons marked with b have 3 neighboring protons. Hence splitting of signal = 3+1 = 4 (quatret) → The protons marked with c do not have neighboring protons. Therefore splitting of signal = 0+1=1 (singlet). (ppm-value splitting pattern Location in molecule triplet (t) Protons marked by a singlet (s) Protons marked lay c' I quateret (9) Protons marted by 'bil 1.9 2.2 H₂ C - c (s, ligppm) o- CH₂ - CH₂ (t, o. 8ppm) (1, 2.2 ppm)