CHEM 3332 1st Edition Lecture 15Outline of Last Lecture I. Friedel-Crafts Acylation – solves some problems with F-C alkylationA. Synthesis of a necessary reagent – the acyl chlorideB. Generation of E+C. Advantages of acylation over alkylation1. Polyacylation is not a problem2. No C+ rearrangement, so F-C acylation is best method for synthesizing unbranched alkylbenzenesD. Gatterman-Koch Formlyation: The Proper Synthesis of BenzaldehdeReactions of Substituted BenzenesHow does a substituent on the benzene ring affect the 5 EAS reactions?I. Reactivity (rxn rate): 2 types of substituents causes ring to be more reactive than beforeII. Orientation of the incoming group: 2 types of substituents: ortho/para directorsException: halogens, O/POutline of Current Lecture Substituents as Activators/DeactivatorsHow do substituents affect reactivity?An electron releasing substituent:An electron withdrawing substituentThe electron withdrawl takes place in two ways:I. Inductive: differences in the electronegativities of the atoms-CH3-CLII. Resonance:Activator:Deactivator:Substituents as Directors:Meta Directors:Ortho ResultPara ResultMeta ResultOrtho/Para Directors:Orto Result:These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Para Result:Meta Result:The Special Case of the Halogens:Deactivating:Orth/Para Directing:Examples:1.2.3.Synthetic Applications:Orientation in Disubstituted BenzenesI. The “No Brainer” Case:II. A Bigger ChallengeIII. The Biggest Challenge:Examples: Current
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