有机质谱

1第二章有机质谱MassSpectroscopy,MSOrganicMassSpectroscopy,OMS2烷烃：CnH2n+1(主)，m/z29，43,57,71,85,99,113,CnH2n,CnH2n-1环烷烃：41,55,56,69,CnH2n-1，CnH2n烯烃：CnH2n-1(主),如m/z41,55,69,83,CnH2n，CnH2n+1环烯：54，68，CnH2n-2，CnH2n-3，醇：CnH2n+1O，31，45，59，CnH2n+1，CnH2n-1(M-18-28,M-18)，CnH2n-2醚：CnH2n+1O的含氧碎片,31,45,59，CnH2n+143,57,71,85,99,113，CnH2n,CnH2n-1峰3硫醇:M-33(-HS),M-34(-H2S),33HS+,34H2S+·，CnH2n+1S的含硫碎片,47,61,75,89···.CnH2n+1(43,57,71,85,99,113···),CnH2n和CnH2n-1胺：CnH2n+2N的含N特征峰,30,44,58,···30+14n.芳香族：M+·强或中等强度。91强峰，γ-H重排92峰，52或66，40或65，39峰或77，78，51苯酚和芳香醚：94，66，40，65，39苯胺：93，66，65，39卤代物：RFM-19,M-20(-F,-HF),CnH2n+1,CnH2nRCl(Br),同位素峰簇,M-35,M-36(-Cl,-HCl)4羧酸M17,M45,45(COOH),59,73,(-H)60羧酸特征峰脂肪醛：M-1,M-29及R+碎片离子,29强峰，43，57，71，44，58，72+14n.酮：RCO+，R+离子,43，57，71，58，72+14n.酯甲酯M31(MOCH3)，乙酯M45(MOC2H5)CnH2nCOOR含氧碎片59+14n峰，（-H）74+14n峰长链酯的双氢重排峰m/z61+14n561008090100605030204070020406080100120140%OFBASEPEAK1030507090110130150Figure2.14.MethylOcatanoateCOCH3OCH2CH2OCH3O121[M-31]MM+1M+2MethyloctanoateCH3(CH2)6COOCH3158(M)159(M+1)160(M+2)160875974COHOCH3H2C7EthylpropionateMwis102,57isformedbylossof45(OCH2CH3)from102.Butylformatewouldnotproducealarge57.Isopropylethanoatewouldproduceanintense43peakandno578C6H12O2(morethan45isomers,suchas:hexanoicacid，isobutylacetate)两种异构体的质谱图(丙酸丙酯,丙酸异丙酯?)M29M41（酯的双氢重排）C2H5CO93-甲基丁酸甲酯M31H2CCOHOCH3+.M15M42106080100120140160020406080100.162(M+)1311037751RIm/zC6H5C2H2COOCH3M31(OCH3)M59(COOCH3)M59-26(C2H2COOCH3)11COOCH3O+.+.+.+.m/z162m/z131m/z103m/z7712C9H10O2的质谱图（a,b,c…）M59(COOCH3)M15m/z135,M15119,M31118,M32苯乙酸甲酯C6H5CH2COOCH313M31(OCH3)MCH3OH)邻甲基苯甲酸甲酯o-CH2C6H5COOCH3M31-28（COOCH3)Whyortho-?P46第一行右M1514Benzoicacid,4-methyl-,methylesterBenzoicacid,3-methyl-,methylesterm/z135,M15119,M31无118,M3215苯甲酸乙酯105:M45(OC2H5)16SearchResults44matchingspecieswerefound.Benzoicacid,ethylester(C9H10O2)2-Methoxy-4-vinylphenol(C9H10O2)Benzylethanoate(C9H10O2)Benzeneaceticacid,methylester(C9H10O2)Acetophenone,4'-methoxy-(C9H10O2)3-Phenylpropanoicacid(C9H10O2)Aceticacid,4-methylphenylester(C9H10O2)Benzoicacid,4-methyl-,methylester(C9H10O2)Oxirane,(phenoxymethyl)-(C9H10O2)Ethanone,1-(3-methoxyphenyl)-(C9H10O2)Benzoicacid,3,4-dimethyl-(C9H10O2)Benzoicacid,2-methyl-,methylester(C9H10O2)Benzoicacid,3-methyl-,methylester(C9H10O2)Benzoicacid,2,5-dimethyl-(C9H10O2)Benzoicacid,3,5-dimethyl-(C9H10O2)Benzoicacid,2,3-dimethyl-(C9H10O2)Benzoicacid,2,6-dimethyl-(C9H10O2)Benzoicacid,2,4-dimethyl-(C9H10O2)Benzaldehyde,4-ethoxy-(C9H10O2)Aceticacid,3-methylphenylester(C9H10O2)Aceticacid,2-methylphenylester(C9H10O2)1,3-Dioxolane,2-phenyl-(C9H10O2)Ortho-methoxyacetophenone(C9H10O2)3-Methyl-p-anisaldehyde(C9H10O2)4-Ethylbenzoicacid(C9H10O2)Benzaldehyde,2-ethoxy-(C9H10O2)Ethanone,1-(2-hydroxy-5-methylphenyl)-(C9H10O2)Benzeneaceticacid,α-methyl-(C9H10O2)1H-Indene-1,2-diol,2,3-dihydro-,cis-(C9H10O2)2H-1,5-Benzodioxepin,3,4-dihydro-(C9H10O2)Propanoicacid,phenylester(C9H10O2)4-Hydroxy-3-methylacetophenone(C9H10O2)4-Hydroxy-2-methylacetophenone(C9H10O2)1H-Indene-1,2-diol,2,3-dihydro-,trans-(C9H10O2)ortho-Hydroxypropiophenone(C9H10O2)p-Tolylaceticacid(C9H10O2)m-Tolylaceticacid(C9H10O2)1-Propanone,1-(4-hydroxyphenyl)-(C9H10O2)Benzeneaceticacid,α-methyl-,(R)-(C9H10O2)Benzeneaceticacid,α-methyl-,(S)-(C9H10O2)2-Propanone,1-phenoxy-(C9H10O2)O-tolylaceticacid(C9H10O2)4-Chromanol(C9H10O2)Benzaldehyde,3-ethoxy-(C9H10O2)羰基化合物---酰胺及氨基酸类酰胺类化合物的裂解反应与酯类化合物类似有明显的分子离子峰-裂解:44+14n,43+14n-氢的重排:59+14n-氢的转移:44+14n,3018RCH2ONR'R''R''R'NCO+RCH2R'R''N+CO+orH2CCOHNR'R''RCH2CONR'CH2R'HNCH2H2NCH2-HRCHCOH++++.m/z44+14nm/z43+14nor16+14nm/z59+14nm/z44+14nm/z3019Propanamide:Mwis73,44isformedbylossof29(CH2CH3)from73.N,N-Dimethylformamidewouldnotproduceanintense44fragmentinsteadofmolecularion.(73highestpeak).20分子式C11H15NO两种异构体的质谱图如下，解释之4060801001201401601800204060801005177148177135105RIm/zM29(C2H5)M42(C3H7)-氢的重排21CH2CH2CH2NHCOCH391597387HCONHCH2CH2CH2CH3105134148m/z135-H-氢的重排224060801001201401601800204060801005139659111817773RIm/z-氢的重排23习题P62-1-1某质谱图高m/z区离子的m/z及RI如下推导其分子式m/z:6162636465RI:8.71004.8310.7835Cl4C?37ClC2H3Cl241.AC2H3Cl,分子离子峰为62，因为M:(M+2)=100:31≈3:1,含一个Cl，62-35=27，所以含-C2H3，为C2H3Cl，UN=1（不饱和度为1）。251BC2H6S分子离子峰为62，因为M:(M+2)/=100:4.4,说明可能含一个S，62-32=30，所以最多还有2个C，则含-C2H6，为C2H6S，UN=0（不饱和度为0）。若含1个C，则含1个O，(M+2)/M=（4.4+0.2）%与已知不符，(M+1)/M=1.1+0.8也与已知值3.8相差较远；且该结构CH2OS不存在。所以应为C2H6S.262.C2H2Cl2,ClCH=CHCl假设分子离子峰为96，因为M:(M+2)：（M+4）=67：43：7≈9：6:1,含二个Cl（2*32.5%），96-2*35=26，所以只能含-C2H2，为C2H2Cl2，UN=1。27质谱图中常见低质荷比碎片离子及可能来源见表２.９。熟悉这些离子及其可能来源对解析质谱及推导化合物的结构大有帮助。表２.8,-氢的重排28某化合物谱图如下，试推断其结构。m/z=100(M),20%m/z=101(M+1),1.34%m/z=102(M+2),0.08%29习题P64-5c结构未知（C6H12O，酮）解析：1．100，分子离子峰2．85，失去CH3（15）的产物3．57,丰度最大,稳定结构失去CO(28)后的产物4.(CH3)3C-CO-CH3习题P64-5aseeP40fig2.1830本章的主要内容第一节质谱基本知识第二节分子离子峰和分子式第三节有机分子裂解类型与过程第四节各类有机化合物的质谱第五节质谱解析及应用大分子质谱的发展与应用31第五节质谱解析及应用32质谱解析一般程序1)标出各峰的质荷比数，尤其注意高质荷比区的峰2)识别分子离子峰。高质荷比区假定分子离子峰，判断其与相邻碎片离子峰关系是否合理3)查看有否A+2元素(Cl,Br,SiorS)查看A+1峰,计算碳原子数，推算N，O的数目，再推算H的数目CxHyNzOw(Ss)RI(M+1)/RI(M)×100=1.1x+0.37z+0.8sRI(M+2)/RI(M)×100=（1.1x）2/