1、3.1COOH(生成酯)COOHNaOHNaHCO3,Na2CO3RCOORNa钠盐与一级活泼卤代烷反应,生成酯:COORNaCH2SN2COORCICH2+NaCI+H2O+重金属盐与卤代烷反应,生成酯(对C=C无影响):COORAg+CICH3CH3SN2COOR+AgCICOOHR CH2N2-+CH3COOR+N2CH2NN-+H+CH3NN+CH3+N23.2 H的卤化RCH2COOHX2PX3RCHCOOHXX2PX3RC-COOHXXRCHCOONaXNaCNRCHCOONaCNH3O+RCHCOOHCOOH3.3COOH生成羧酸衍生物3.3.1 酯化反应COOHRORH+HCO
2、R+H2OORROH的反应活性:1 23 酯化反应机理(1 2 ROH):RCOHOOH2R+COORRH+H2OH+-COORRCOOHRH+COOHRH+ROHRCOHO+OHHRCOOHCH3H+C2H5OH*COOC2H5CH3+H2O*当用叔醇时,用不同的机理:COOHRH+COOC(CH3)3R+H2O+(CH3)3COH*(CH3)3C-OHH+(CH3)3C-OH2+*(CH3)3C+-H2O*COOHR(CH3)3C+COC(CH3)3OHR+-H+COOC(CH3)3RCOOH浓硫酸COOH2+-H2OCO+ROHCOORH+COOR-H+3.3.2 形成酰卤1.制酰氯:S
3、OCI2PCI5PCI3COOHR+CISCIOCOROSOCI+HCICOCIR+SO2+HCICOOHRPCI3COCIR+H3PO3PCI5)(POCI3+HCI()2.制酰溴:用PBr3COOHRPBr3COBrR3.3.3 形成酸酐COOHR2去水剂COORCOR+H2OCOOHRNaOHCOONaRCOCIRCOORCOR+NaCI3.3.4形成酰胺羧酸与NH3RNH2R2NH反应COOHR+NH3COONH4RCONH2R+H2OCO-OHRNH3+CO-OH2RNH2+3.4还原反应常用还原剂:LiAlH4(对烯键炔键无影响)B2H6(对烯键炔键有影响)RCOOHLiAlH4醚
4、H2ORCH2OHRCOOHH2ORCH2OHB2H6B2H6的还原反应活性:-COOH C=O -CN-COOR -COCI3.5脱羧反应3.5.1 一元羧酸的脱羧反应1.脱羧成烃RCOONaNaOH,CaORH+CO2COOH+CO22.脱羧成卤代烃汉斯狄克反应(Huns diecker,H.)RCOOHAgNO3KOHRCOOAgBr2CCl4R-Br机理:RCOOAgBr2RCOOBrRCOOBr+RCO2+BrR-Br反应活性:R:123克利斯托反应(Cristol,s.t.)RCOOHHgO,Br2CCl4R-BrCO2+H2O+HgBr2反应活性:R:123柯齐反应(Kochi,J.K.)在金属 Li k Ca 的卤化物与四乙酸铅作用下:RCOOH+Pb(OAc)4+LiCl苯回流RCl+LiOAc+Pb(OAc)2+HOAcR的空间结构对反应的影响不大,反应产率很好3.5.2 二元羧酸的脱羧反应及规律由于-COOH是吸电子基,二元羧酸的脱羧反应 容易进行但两个羧基的空间位置不同,脱去的基团不同.COOHCOOHHCOOHCO2+CO2+H2OCH2COOHCOOHCH3COOHCO2+OOOHOHOOO+H2OOOHOOHOOO+H2OOOHOOHO+H2O+CO2COOHCOOH+H2O+CO2O