Explore key organic chemistry concepts in this 50-minute Yale University lecture. Delve into the regiospecificity of epoxide ring openings, challenging textbook representations and experimental data interpretations. Examine the ozonolysis of alkenes through 1,3-dipolar cycloadditions, analyzing HOMO-LUMO interactions. Investigate acetal hydrolysis and the completion of ozonolysis, including reduction and oxidation pathways. Consider the electrophilic component in nucleophilic additions to carbonyl groups. Conclude with an introduction to metal-catalyzed cycloadditions, focusing on alkene dihydroxylation using osmium tetroxide. Gain insights into reaction mechanisms and deepen your understanding of organic chemistry principles through this comprehensive lecture.