CHED 573 |
| In 2005, Chi and coworkers reported an unusual electrophilic aromatic addition reaction (AdEAr) (J. Org. Chem. 2005, 70, 1222-1226). The AdEAr and electrophilic aromatic substitution (EAS) pathways share a common initial mechanistic step. After one electrophilic aromatic bromination of the usual variety, the addition of a second bromine is thought to proceed with further addition of methanol rather than deprotonation (like in EAS). This addition of methoxy is observed only under basic methanolic conditions. It seems that an intermediate of the AdEAr reaction must be further stabilized. The intermediate seems to be stabilized by a nitrogen containing base or by an excess of NaHCO3. Our initial results indicate that the report of the AdEAr occurs as specified in the above Journal. A variety of compounds were utilized in our research. Our B3LYP/6-31G(d) gas phase and B3LYP/6-31G(d) IEFPCM calculations agree that the EAS products is enthalpically favored over the AdEAr product. |
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Undergraduate Research Poster Session: Organic Chemistry
11:00 AM-1:00 PM, Monday, March 26, 2007 Hyatt Regency Chicago -- Riverside Center, Poster
Division of Chemical Education |