Question

help with 3 and 4

on from risic vent for the ons formed POSTLAB QUESTIONS 1. Sulfuric acid serves three functions in this action: 1) in the format dcia; 2) as the Lewis acid catalyst for electrophilic aromatic substituto reaction by dissolving the methul benzoate. Based on the procond explain why nitration occurs primarily at the meta position and no 2. What two techniques were used in this experiment to prevent dinica 3. What would be the structure of the dinitro ester if it were formed, and w reformed and what is the probability that second nitration reaction would occur in the same ring of methyl- 4. Using the mass spectrum shown below for methyl-m-nitrobenzoqate, patterns by providing structures for major peaks observed in m trum shown below for methyl-m-nitrobenzogate. Interpret the fragmentatie ng structures for major peaks observed in mass spectra, Hint: majoragments are due to bond cleavage next to C=O (alkoxy group loss, -OR) and hydrogen 100 methyl 3-nitrobenzoate in this reaction: 1) in the formation of the nitronium ion from ar electrophilic aromatic substitution; and 3) as the solvent for benzoate. Based on the protonated methyl benzoate ions for position and not at ortho or para. experiment to prevent dinitration of methyl benzoate? e ning of methyl-m-nitrobenzoate? Explain. group loss, -OR) and hydrogen rearrangements. 150 Fraction of Base Peak (%) 104 120 181 0 l l................. l .. M/Z

Answer 1

OCH3 ON HNO3 OCH3 H2SO4 NO2 methyl 3-nitrobenzoate NOZ methyl 3,5-dinitrobenzoate Probability of nitration of methyl-3-nitrobenzoate is very less because nitro and COOCH, both group are strong electron withdrawing. They deactivate the benzene ring. OCH OCH NO2 Chemical Formula: C.H.NO,** m/z: 181 NO2 Chemical Formula: C-HXNO3 m/z: 150.02 (100.0%) Base peak - NO₂ NO2 Chemical Formula: C,H,O*+ m/z: 104 Chemical Formula: C.H.** m/z: 76