有机化学英文chapter.pdf

Chapter 10 Aldehydes and Ketones In this and next chapters, we will discuss the most important functional group in organic chemistry — the carbonyl group, C=O. Carbonyl compounds are everywhere in nature. Most biologically important molecules contain carbonyl-groups, as do many pharmaceutical agents and many of the synthetic chemicals that touch our everyday lives. Biochemistry is carbonyl chemistry. Almost all metabolic processes used by all living organisms involve one or more of four fundamental carbonyl-group reactions we will discuss in this and next chapters. The digestion and metabolic breakdown of all the major classes of food molecules—fats, carbohydrates, and proteins — take ce by nucleophilic addition reaction, nucleophilic acyl substitutions, a substitution, and carbonyl condensations. Similarly, hormones and other crucial biological molecules are built up from smaller precursors by the same carbonyl-group reactions. 1 H C 3 C O H C 3 2 2p 2p H 2s C = O hybridization H 2p 2 used for sp p bond used for s bonds H C O H 3 9.1 Structure of Carbonyl Groups Carbon-oxygen double bond Carbon-carbon double bond ： C O C C ： C=O C=C Electronegativity: