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首页 吡啶及其衍生物(英文)

吡啶及其衍生物(英文).pdf

吡啶及其衍生物(英文)

zxliaohz
2010-06-14 0人阅读 举报 0 0 暂无简介

简介:本文档为《吡啶及其衍生物(英文)pdf》,可适用于考试题库领域

PYRIDINEANDPYRIDINEDERIVATIVESSincetheearlytwentiethcentury,pyridinederivativeshavebeencommerciallyimportant,butmostprominentlysoduringWorldWarIIandthereafterManypyridinesofcommercialinterestfindapplicationinmarketareaswherebioactivityisimportant,asinmedicinaldrugsandinagriculturalproductssuchasherbicides,insecticides,fungicides,andplantgrowthregulatorsHowever,pyridinesalsohavesignificantmarketapplicationsoutsidetherealmofbioactiveingredientsForinstance,polymersmadefrompyridinecontainingmonomersaregenerallysoldonthebasisoftheiruniquephysicalpropertiesandfunction,ratherthanforanybioactivityPyridinescanbeclassifiedasspecialtychemicalsbecauseofarelativelylowersalesvolumethancommoditychemicalsTheyaremostoftensoldinthemarketplaceaschemicalintermediatesusedtomanufacturefinalconsumerproductsPyridinecompoundsaredefinedbythepresenceofasixmemberedheterocyclicringconsistingoffivecarbonatomsandonenitrogenatomThecarbonvalenciesnottakenupinformingtheringaresatisfiedbyhydrogenatomsThearrangementofatomsissimilartobenzeneexceptthatoneofthecarbon−hydrogenringsetshasbeenreplacedbyanitrogenatomTheparentcompoundispyridineitself()Substituentsareindicatedeitherbythenumberingshown,through,orbytheGreekletters,α,βorγTheGreeksymbolsrefertothepositionofthesubstituentrelativetotheringnitrogenatom,andareusuallyusedfornamingmonosubstitutedpyridinesTheortho,meta,andparanomenclaturecommonlyusedfordisubstitutedbenzenesisnotusedinnamingpyridinecompoundsImportantcommercialalkylpyridinecompoundsareαpicoline(),βpicoline(),γpicoline(),,lutidine(),,lutidine(),ethylmethylpyridine(),and,,collidine()Ingeneral,thealkylpyridinesserveasprecursorsofmanyothersubstitutedpyridinesusedincommerceThesefurthersubstitutedpyridinecompoundsderivedfromalkylpyridinesareinturnoftenusedasintermediatesinthemanufactureofcommerciallyusefulfinalproductsPYRIDINEANDPYRIDINEDERIVATIVESSincetheearlytwentiethcentury,pyridinederivativeshavebeencommerciallyimportant,butmostprominentlysoduringWorldWarIIandthereafterManypyridinesofcommercialinterestfindapplicationinmarketareaswherebioactivityisimportant,asinmedicinaldrugsandinagriculturalproductssuchasherbicides,insecticides,fungicides,andplantgrowthregulatorsHowever,pyridinesalsohavesignificantmarketapplicationsoutsidetherealmofbioactiveingredientsForinstance,polymersmadefrompyridinecontainingmonomersaregenerallysoldonthebasisoftheiruniquephysicalpropertiesandfunction,ratherthanforanybioactivityPyridinescanbeclassifiedasspecialtychemicalsbecauseofarelativelylowersalesvolumethancommoditychemicalsTheyaremostoftensoldinthemarketplaceaschemicalintermediatesusedtomanufacturefinalconsumerproductsPyridinecompoundsaredefinedbythepresenceofasixmemberedheterocyclicringconsistingoffivecarbonatomsandonenitrogenatomThecarbonvalenciesnottakenupinformingtheringaresatisfiedbyhydrogenatomsThearrangementofatomsissimilartobenzeneexceptthatoneofthecarbon−hydrogenringsetshasbeenreplacedbyanitrogenatomTheparentcompoundispyridineitself()Substituentsareindicatedeitherbythenumberingshown,through,orbytheGreekletters,α,βorγTheGreeksymbolsrefertothepositionofthesubstituentrelativetotheringnitrogenatom,andareusuallyusedfornamingmonosubstitutedpyridinesTheortho,meta,andparanomenclaturecommonlyusedfordisubstitutedbenzenesisnotusedinnamingpyridinecompoundsImportantcommercialalkylpyridinecompoundsareαpicoline(),βpicoline(),γpicoline(),,lutidine(),,lutidine(),ethylmethylpyridine(),and,,collidine()Ingeneral,thealkylpyridinesserveasprecursorsofmanyothersubstitutedpyridinesusedincommerceThesefurthersubstitutedpyridinecompoundsderivedfromalkylpyridinesareinturnoftenusedasintermediatesinthemanufactureofcommerciallyusefulfinalproductsPYRIDINEANDPYRIDINEDERIVATIVESVolKirkOthmerEncyclopediaofChemicalTechnology(thEdition)Asisthecasewithmostspecialtyorganiccompounds,pyridinesalesaregenerallynotpublicized,andindustrialprocessesfortheirmanufactureareeitherretainedastradesecretsorpatented(seePATENTSANDTRADESECRETS)Uptoabout,mostpyridineswereisolatedfromcoaltarfractionshowever,aftersyntheticmanufacturebegantotakeaneverincreasingshareofproductssoldBy,overofallpyridineswereproducedbysyntheticmethodsPyridinewasfirstsynthesizedin()fromacetyleneandhydrogencyanideHowever,αpicoline()wasthefirstpyridinecompoundreportedtobeisolatedinpureform()Interestingly,itwasthemarketneedfor()thatmotivatedthedevelopmentofsyntheticprocessesforpyridinesduringthes,inpreferencetotheirisolationfromcoaltarsourcesThebasisformostcommercialpyridinesynthesesinusecanbefoundintheearlyworkofChichibabin()Therearefewselectivecommercialprocessesforpyridine()anditsderivatives,andalmostallmanufacturingprocessesproduce()alongwithaseriesofalkylatedpyridinesinadmixtureThechemistryofpyridinesissignificantlydifferentfromthatofbenzenoidsPyridinesundergosometypesofreactionthatonlyhighlyelectrondeficientbenzenoidsundergo,anddonotundergosomefacilereactionsofbenzenoids,suchasFriedelCraftsalkylationandCacylation,forexamplePhysicalPropertiesThephysicalpropertiesofpyridinesaretheconsequenceofastable,cyclic,πelectron,πdeficient,aromaticstructurecontainingaringnitrogenatomTheringnitrogenismoreelectronegativethantheringcarbons,makingthetwo,four,andsixringcarbonsmoreelectropositivethanotherwisewouldbeexpectedfromaknowledgeofbenzenoidchemistriesThearomaticπelectronsystemdoesnotrequiretheparticipationofthelonepairofelectronsonthenitrogenatomhencethetermsweaklybasicandπdeficientusedtodescribepyridinecompoundsTheringnitrogenofmostpyridinesundergoesreactionstypicalofweak,tertiaryorganicaminessuchasprotonation,alkylation(qv),andacylationLiquidpyridineandalkylpyridinesareconsideredtobedipolar,aproticsolvents,similartodimethylformamideordimethylsulfoxideMostpyridinesformasignificantazeotropewithwater,allowingseparationofmixturesofpyridinesbysteamdistillationthatcouldnotbeseparatedbysimpledistillationaloneThesameazeotropiceffectwithwateralsoallowsrapiddryingofwetpyridinesbydistillationofasmallforecutofwaterazeotropePyridineManyphysicalpropertiesofpyridineareunlikethoseofbenzene,itshomocycliccounterpartForinstance,pyridinehasaboilingpoint°Chigherthanbenzene(vs°C),andunlikebenzene,itismisciblewithwaterinallproportionsatambienttemperaturesThemuchhigherdipolemomentofpyridinerelativetobenzeneisresponsible,insignificantpart,forthehigherboilingpointandwatersolubilityBenzeneandpyridinearearomaticcompoundshavingresonanceenergiesofsimilarmagnitude,andbotharemisciblewithmostotherorganicsolventsPyridineisaweakorganicbase(pKa=:),beingbothanelectronpairdonorandaprotonacceptor,whereasbenzenehaslittletendencytodonateelectronpairsoracceptprotonsPyridineislessbasicthanaliphatic,tertiaryaminesTablelistssomephysicalpropertiesofpyridine,andTablecomparesphysicalpropertiesofpyridinetosomealkylandalkenylpyridinebasesTablePhysicalPropertiesofPyridinePhysicalpropertyValueenthalpyoffusionat¡:±C,kJmolbenthalpyofvaporization,kJmolbat°C°CAsisthecasewithmostspecialtyorganiccompounds,pyridinesalesaregenerallynotpublicized,andindustrialprocessesfortheirmanufactureareeitherretainedastradesecretsorpatented(seePATENTSANDTRADESECRETS)Uptoabout,mostpyridineswereisolatedfromcoaltarfractionshowever,aftersyntheticmanufacturebegantotakeaneverincreasingshareofproductssoldBy,overofallpyridineswereproducedbysyntheticmethodsPyridinewasfirstsynthesizedin()fromacetyleneandhydrogencyanideHowever,αpicoline()wasthefirstpyridinecompoundreportedtobeisolatedinpureform()Interestingly,itwasthemarketneedfor()thatmotivatedthedevelopmentofsyntheticprocessesforpyridinesduringthes,inpreferencetotheirisolationfromcoaltarsourcesThebasisformostcommercialpyridinesynthesesinusecanbefoundintheearlyworkofChichibabin()Therearefewselectivecommercialprocessesforpyridine()anditsderivatives,andalmostallmanufacturingprocessesproduce()alongwithaseriesofalkylatedpyridinesinadmixtureThechemistryofpyridinesissignificantlydifferentfromthatofbenzenoidsPyridinesundergosometypesofreactionthatonlyhighlyelectrondeficientbenzenoidsundergo,anddonotundergosomefacilereactionsofbenzenoids,suchasFriedelCraftsalkylationandCacylation,forexamplePhysicalPropertiesThephysicalpropertiesofpyridinesaretheconsequenceofastable,cyclic,πelectron,πdeficient,aromaticstructurecontainingaringnitrogenatomTheringnitrogenismoreelectronegativethantheringcarbons,makingthetwo,four,andsixringcarbonsmoreelectropositivethanotherwisewouldbeexpectedfromaknowledgeofbenzenoidchemistriesThearomaticπelectronsystemdoesnotrequiretheparticipationofthelonepairofelectronsonthenitrogenatomhencethetermsweaklybasicandπdeficientusedtodescribepyridinecompoundsTheringnitrogenofmostpyridinesundergoesreactionstypicalofweak,tertiaryorganicaminessuchasprotonation,alkylation(qv),andacylationLiquidpyridineandalkylpyridinesareconsideredtobedipolar,aproticsolvents,similartodimethylformamideordimethylsulfoxideMostpyridinesformasignificantazeotropewithwater,allowingseparationofmixturesofpyridinesbysteamdistillationthatcouldnotbeseparatedbysimpledistillationaloneThesameazeotropiceffectwithwateralsoallowsrapiddryingofwetpyridinesbydistillationofasmallforecutofwaterazeotropePyridineManyphysicalpropertiesofpyridineareunlikethoseofbenzene,itshomocycliccounterpartForinstance,pyridinehasaboilingpoint°Chigherthanbenzene(vs°C),andunlikebenzene,itismisciblewithwaterinallproportionsatambienttemperaturesThemuchhigherdipolemomentofpyridinerelativetobenzeneisresponsible,insignificantpart,forthehigherboilingpointandwatersolubilityBenzeneandpyridinearearomaticcompoundshavingresonanceenergiesofsimilarmagnitude,andbotharemisciblewithmostotherorganicsolventsPyridineisaweakorganicbase(pKa=:),beingbothanelectronpairdonorandaprotonacceptor,whereasbenzenehaslittletendencytodonateelectronpairsoracceptprotonsPyridineislessbasicthanaliphatic,tertiaryaminesTablelistssomephysicalpropertiesofpyridine,andTablecomparesphysicalpropertiesofpyridinetosomealkylandalkenylpyridinebasesTablePhysicalPropertiesofPyridinePhysicalpropertyValueenthalpyoffusionat¡:±C,kJmolbenthalpyofvaporization,kJmolbat°C°CPYRIDINEANDPYRIDINEDERIVATIVESVolKirkOthmerEncyclopediaofChemicalTechnology(thEdition)criticaltemperature,°Ccriticalpressure,MPacenthalpyofformation,gasat°C,kJmolbGibbsfreeenergyofformation,gasat°C,kJmolbheatcapacity,gasat°C,J(K¢mol)ignitiontemperature,°Cexplosionlimit,−surfacetension,liquidat°C,mN=m(=dyn=cm)viscosity,liquidat°C,mPa(=cP)dielectricconstant,liquidat°C,εthermalconductivity,liquidat°C,W(K¢m)aRefbToconvertkJtocal,dividebycToconvertMPatoatm,multiplybyTablePhysicalPropertiesofPyridine,Alkyl,andAlkenylpyridineDerivativesaWaterazeotropeCompoundCASRegistryNumberStructurenumberMolwtFreezingpoint,°CBoilingpoint,°CDensity,dIndexofrefraction,nWatersolubilitybat°C,gmLpKaat°C,inwatercBpd,°CWater,pyridine()¡:epicolinef,g()¡:epicolineg()¡:epicolinef,g()e,lutidine()¡:,lutidine¡e,lutidine¡:,lutidine()¡:e,lutidine¡:,lutidine()¡:,,collidine()¡:ethylmethylpyridine()¡:vinylpyridine()hvinylpyridinehaRef,unlessotherwisenotedbRefcRefdRefeMisciblefIgnitiontemperature=±Cfor()and°Cfor()gExplosionlimit=::for()and−for()and()hAtkPa(mmHg)OtherPyridineBasesThenucleophilicityandbasicityofpyridinescanbereducedbylarge,stericallybulkygroupsaroundthenitrogenatom,suchastertbutylintheandpositionsStericallyundemandinggroupslikemethyltendtoincreasebasicityrelativetoparentpyridine,asexpectedElectronwithdrawingsubstituentscanalsoreducepyridinebasicityandnucleophilicity,DichloropyridineisstericallyhinderedandalsocontainsstrongelectronwithdrawingsubstituentsAssuch,itcannotbetitratedbyacid,evenbyusingextremelyacidicmediasuchasperchloriccriticaltemperature,°Ccriticalpressure,MPacenthalpyofformation,gasat°C,kJmolbGibbsfreeenergyofformation,gasat°C,kJmolbheatcapacity,gasat°C,J(K¢mol)ignitiontemperature,°Cexplosionlimit,−surfacetension,liquidat°C,mN=m(=dyn=cm)viscosity,liquidat°C,mPa(=cP)dielectricconstant,liquidat°C,εthermalconductivity,liquidat°C,W(K¢m)aRefbToconvertkJtocal,dividebycToconvertMPatoatm,multiplybyTablePhysicalPropertiesofPyridine,Alkyl,andAlkenylpyridineDerivativesaWaterazeotropeCompoundCASRegistryNumberStructurenumberMolwtFreezingpoint,°CBoilingpoint,°CDensity,dIndexofrefraction,nWatersolubilitybat°C,gmLpKaat°C,inwatercBpd,°CWater,pyridine()¡:epicolinef,g()¡:epicolineg()¡:epicolinef,g()e,lutidine()¡:,lutidine¡e,lutidine¡:,lutidine()¡:e,lutidine¡:,lutidine()¡:,,collidine()¡:ethylmethylpyridine()¡:vinylpyridine()hvinylpyridinehaRef,unlessotherwisenotedbRefcRefdRefeMisciblefIgnitiontemperature=±Cfor()and°Cfor()gExplosionlimit=::for()and−for()and()hAtkPa(mmHg)OtherPyridineBasesThenucleophilicityandbasicityofpyridinescanbereducedbylarge,stericallybulkygroupsaroundthenitrogenatom,suchastertbutylintheandpositionsStericallyundemandinggroupslikemethyltendtoincreasebasicityrelativetoparentpyridine,asexpectedElectronwithdrawingsubstituentscanalsoreducepyridinebasicityandnucleophilicity,DichloropyridineisstericallyhinderedandalsocontainsstrongelectronwithdrawingsubstituentsAssuch,itcannotbetitratedbyacid,evenbyusingextremelyacidicmediasuchasperchloricPYRIDINEANDPYRIDINEDERIVATIVESVolKirkOthmerEncyclopediaofChemicalTechnology(thEdition)acidinaceticacidsolventGenerally,hydrophobicsubstituentsonthepyridineringreducewatersolubility,polaronescapableofhydrogenbondingasacceptorordonor,increaseitTablegivesthecorrespondingphysicalpropertiesofsomecommerciallyimportantsubstitutedpyridineshavinghalogen,carboxylicacid,ester,carboxamide,nitrile,carbinol,aminomethyl,amino,thiol,andhydroxylsubstituentsTablePhysicalPropertiesofSubstitutedPyridinesaCompoundCASRegistryNumberStructurenumberMolwtFreezingpoint,°CBoilingpoint,°CDensity,dIndexofrefraction,nDWatersolubilitybat°C,gmLpKacat°Cinwaterchloropyridine()¡:−d,dichloropyridine−efbromopyridine−picolinicacidg−hnicotinicacidi()−hisonicotinicacidj−hmethylpicolinatekethylnicotinate−−picolinamidedeclnicotinamide()−cyanopyridine()−−¡:cyanopyridine()−mcyanopyridine()npyridylcarbinol()¡:opyridylcarbinol−popicolylamineopicolylamine¡:omercaptopyridine−¡:mercaptopyridine−pyridone()>hydroxypyridine()pyridone()q>aminopyridine()>aminopyridine()>aminopyridine()dimethylaminopyridine()raMeasur

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吡啶及其衍生物(英文)

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