The goal of this lab was to prepare methyl m-nitrobenzoate using electrophilic aromatic substitution. An example of electrophilic aromatic substitution is nitration where a hydrogen atom which is part of a aromatic ring is substituted by an electrophile. For benzene, aromaticity is a stabilizing feature. As such, instead of undergoing electrophilic additions, it undergoes electrophilic substitutions. The nitronium ion is the electrophile which gets attached to the electron rich aromatic ring. Given that benzene rings have low reactivity, the electrophile needs to be very reactive. Also, the electrophile attack can happen at 3 distinct locations, the meta, para or ortho locations, where the substitution takes place. Depending upon where the substitution takes place, the electron density changes, resulting in considerably different reactivity differences1.
The reaction used methyl benzoate and a mixture of nitric and sulfuric …show more content…
There is evidence of 5 distinguishable peaks suggesting 7 protons. Based on the rule of n+1 and spin-spin coupling, the hydrogen peaks identified by c and b in Figure 4 show 2 sub-peaks because of the 1 proton C in the neighborhood. In this case n=1, implying n+1=2 (sub-peaks). Using the same reasoning for Hd, there are 2 protons in the neighborhood: Hc and Hb. This implies 3 sub-peaks, which can be identified in Figure 2. For He and Ha, protons in the neighborhood are absent. As such, n+1=1, indication a multiplicity of 1.
All this confirms the synthesis of the final product. The experiment demonstrated that benzene can undergo substitution reactions that are electrophilic aromatic substitution reactions. Given that benzene rings are used commonly in the production of many organic compounds, the capability to make substitutions to benzene is critical. The NMR and IR spectra results confirmed the identity of the final product. The percent yield was also reasonable.
The reaction used methyl benzoate and a mixture of nitric and sulfuric …show more content…
There is evidence of 5 distinguishable peaks suggesting 7 protons. Based on the rule of n+1 and spin-spin coupling, the hydrogen peaks identified by c and b in Figure 4 show 2 sub-peaks because of the 1 proton C in the neighborhood. In this case n=1, implying n+1=2 (sub-peaks). Using the same reasoning for Hd, there are 2 protons in the neighborhood: Hc and Hb. This implies 3 sub-peaks, which can be identified in Figure 2. For He and Ha, protons in the neighborhood are absent. As such, n+1=1, indication a multiplicity of 1.
All this confirms the synthesis of the final product. The experiment demonstrated that benzene can undergo substitution reactions that are electrophilic aromatic substitution reactions. Given that benzene rings are used commonly in the production of many organic compounds, the capability to make substitutions to benzene is critical. The NMR and IR spectra results confirmed the identity of the final product. The percent yield was also reasonable.