Organic Chemistry II CHEM-2425 Ch 21 Substitution Reactions at the Alpha Carbon Part 1

Chapter 21 Lecture Video Part 1 Section 21.1 Introduction: Brief introduction to reactions at the alpha carbon. Section 21.2 Enols: Identify the two factors that stabilize the formation of enols. Convert the keto form to the enol form, or vice versa. Draw the mechanism of enol tautomerization in both acid and base. Section 21.3 Enolates: Know the approximate pKa of an α-hydrogen on the compounds in Table 21.2 and determine what bases are strong enough (Table 21.3) to deprotonate those hydrogens. Draw the resonance structures (and the hybrid) that explains the stabilization of enolates. Section 21.4 Enolates of Unsymmetrical Carbonyl Compounds: Explain which enolate is the kinetic enolate and which is the thermodynamic enolate in an unsymmetrical carbonyl compound. Choose the correct base to form each. Section 21.5 Racemization at the α Carbon: Explain why racemization occurs when the α-carbon is a stereogenic center during enolate formation. Section 21.6 A Preview of Reactions at the Alpha Carbon: Brief preview of reactions coming up later in the chapter. These are the lectures that I use in my Organic Chemistry II course. The textbook I use is Smith, Janice "Organic Chemistry", McGraw Hill, 6th Ed., 2020, ISBN13: 9781260119107. Some images used in this video come from that textbook.