第十一章-2第四军医大学药学.pptVIP

4) Alcoholysis of Amides;3.1.3. Ammonolysis;2) Ammonolysis of Acid Anhydrides;3) Ammonolysis of Esters;4) Ammonolysis of Amides and Nitriles;3.1.4. Reaction of Acyl Chlorides with the Salts of Carboxylic Acids;Summary of Interconversion of Carboxylic Acid Derivatives;;;3.2. Reaction with Organometallic Reagents;Mechanism:;3) Reaction with a 2°amide gives a ketone;3.2.2. Reaction with Organolithium Reagents;3.2.3. Reaction of Acyl Chlorides with Lithium Diorganocuprates;3.3. Reduction;2) Reduction with NaBH4;3.3.2. Dissolving-Metal Reduction;3.3.3. Hydrogenation;;Imides (pKa 8–10) are considerably more acidic than amides and readily dissolve in 5% aqueous NaOH by forming water-soluble salts, because the anion formed by ionization of an imide delocalize the negative charge on nitrogen and the two carbonyl oxygens.;3.4.2. Hofmann rearrangement;Mechanism ;Hofmann rearrangement: Intramolecular or intermolecular?;Stereochemistry at the migrating group:;3.4.3. Dehydration;Thioesters;If thioester is added to the order of reactivity, the sequence is as following:;Biological Acylation; Many biochemical acylations involve transfer of acyl groups from thioesters of coenzyme A (CoA);4. Derivatives of Carbonic Acid and Orthocarboxylic acids;A derivative of carbonic acid containing an OH group is unstable, and decomposes to carbon dioxide. ;Some important derivatives of carbonic acid are stable. Fox example:;Most derivatives of carbonic acid are made from one of three industrially available compounds: phosgene, urea, or cyanamide.;4.1.1. Phosgene, COCl2 A highly poisonous gas, is manufactured by the reaction between carbon monoxide and chlorine.;4.1.2. Urea, H2NCONH2 Urea is excreted in the urine as the chief nitrogen-containing end product of protein metabolism.;Treatment of urea with acid chlorides or anhydrides yields ureides;Urea is heated above melting point to give biuret ;;Guanidine, pKa 13.6, is almost as basic as hydroxide ion. Its conjugate acid is a weaker acid than a