A synthesis of the broad–spectrum antibiotic, metronidazole, is outlined below:

i) Suggest a mechanism to account for Step 1 in the sequence. (3 marks) 

ii) Suggest a mechanism to account for Step 3 in the sequence. In your answer explain the reason for the regioselectivity of this transformation. (4 marks)

Transcribed Image Text:

2 equivalents heat in acetic acid NH3 H. H3C H. Step 1 NH ČH3 1. conc. HNO3/ conc. H2SO4 Step 2 2. neutralisation NO2 NO2 ZON N. NH HN N. N. Step 3 CH3 CH3 CH3 2-methyl-4(5)-nitroimidazole metronidazole 2 equivalents heat in acetic acid NH3 H. H3C H. Step 1 NH ČH3 1. conc. HNO3/ conc. H2SO4 Step 2 2. neutralisation NO2 NO2 ZON N. NH HN N. N. Step 3 CH3 CH3 CH3 2-methyl-4(5)-nitroimidazole metronidazole

Answer rating: 100% (QA)

1 In step 1 1 mol of glyoxal reacts with 2 mols of ammo... View the full answer