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Zonse Zimene Mukuyenera Kudziwa Zokhudza Pyridines

Zonse Zimene Mukuyenera Kudziwa Zokhudza Pyridines

Zonse Zimene Mukuyenera Kudziwa Zokhudza Pyridines

Pyridine ndizofunikira heterocyclic chigawo cha mtundu wa azine. Pyridine imachokera ku benzeni kupyolera mmalo mwa gulu la CH ndi N-atomu. Mapangidwe a Pyridine ali ofanana ndi mawonekedwe a benzene, chifukwa akugwirizana ndi kubwezeretsedwa kwa CH gulu ndi N. Kusiyanitsa kwakukulu kukuphatikizapo:

  1. Kuchokera ku geometry yeniyeni yeniyeni yeniyeni chifukwa cha kukhalapo kwa hetero atomu, kunena momveka bwino, lalifupi nayitrogeni-kaboni zomangira,
  2. Kusintha kwa atomu ya haidrojeni m'mphepete mwa ndegeyo ndi awiri osagwiritsidwa ntchito, monga ndege ya mphete, yomwe ili pamtundu wosakanikirana wa sp2, ndipo sichigwira nawo sextet ya p-electron yonunkhira. Nitrojeni imodzi yokha ndiyo yomwe imayambitsa zinthu zofunika kwambiri za pyridines,
  3. Mphamvu ya dipolomu yokhazikika yomwe imatha kukhala ndi mphamvu yapamwamba yamagetsi ya atomu ya nayitrogeni poyerekeza ndi atomu ya carbon.

Mzere wa Pyridine umapezeka m'magulu angapo ofunikira, kuphatikizapo mavitamini niacin, pyridoxine, komanso mazira.

Katswiri wamagetsi wa ku Scotland, Thomas Anderson anapanga pyridine mu 1849 monga imodzi mwa mankhwala omwe amapanga mafupa a mafupa. Pambuyo pa zaka ziwiri, Anderson anapeza pyridine yoyera ndi distillation ya mafuta a mafupa. Ndi madzi osungunuka kwambiri, osasunthika, osakanikirana ndi madzi, osakanikirana ndi osakanikirana, osunkhira ngati nsomba.

Pyridine imagwiritsidwa ntchito nthawi zonse monga chithunzithunzi cha mankhwala ndi mankhwala a agrochemicals komanso imakhala yosafunika kwambiri komanso yotsekemera. Pyridine ikhoza kuwonjezeredwa ku ethanol ngati mukufuna kuti ikhale yosayenera kuti anthu azidya. Amagwiranso ntchito popanga antihistaminic mankhwala mepyramine ndi tripelennamine, mu vitro kaphatikizidwe ka DNA, pakupanga sulfapyridine (mankhwala ochizira matenda opatsirana ndi matenda a bakiteriya), komanso bactericides, herbicides, ndi madzi otetezera madzi.

Mitundu yambiri yamagulu, ngakhale kuti siidapangidwa kuchokera ku pyridine, ili ndi mapangidwe a mphete. Mankhwalawa amaphatikizapo mavitamini a B monga pyridoxine ndi niacin, chikonga, mankhwala opangidwa ndi nayitrogeni, ndi mankhwala oletsa TB omwe amadziwika ndi isoniazid. Pyridine inalembedwa kalekale monga mankhwala a mafuta a malasha komanso kuchokera ku malasha. Komabe, kufunika kwa pyridine kumapangitsa kuti pakhale njira zopangira ndalama kuchokera ku ammonia ndi acetaldehyde, ndipo matani oposa 20,000 amapangidwa chaka ndi chaka padziko lapansi.

Nomenclature ya pyridine

Dzina lovomerezeka la pyridine, molingana ndi dzina la Hantzsch-Widman lotchulidwa ndi IUPAC, ndilo azine. Koma mayina ovomerezeka pamagulu oyambirira amagwiritsidwa ntchito kawirikawiri; M'malo mwake, dzina la majeremusi limatchula mayina odziwika. IUPAC samalimbikitsa kugwiritsa ntchito azine pamene akutchula pyridine.

Kuwerengera kwa atomu mphete mu azine kumayamba pa nayitrogeni. Kugawa kwa malo omwe ali ndi chilembo chachi Greek (α-γ) ndi mawonekedwe a dzina lomasuliridwa ndi nomenclature omwe amafanana ndi ma homoaromatic systems (para ortho, cholinga,) amagwiritsidwa ntchito nthawi zina. Pano α, β ndi γ akuyang'ana malo awiri, atatu, ndi anayi, motsatira.

Dzina lenileni la zochokera ku pyridine ndi pyridinyl, kumene nambala imatsogolera m'malo amodzi a atomu omwe amatsogoleredwa ndi nambala. Koma dzina la mbiriyakale pyridyl akulimbikitsidwa ndi IUPAC ndipo amagwiritsidwa ntchito kwambiri mmalo mwa dzina lokonzekera. Zomwe zimayambira kupyolera mu kuwonjezera kwa electrophimu kwa atomu ya nayitrogeni imadziwika kuti pyridinium.

4-bromopyridine

2,2'-bipyridine

Dipicolinic acid (pyridine-2,6-dicarboxylic acid)

Njira yofunika kwambiri yopangira pyridinium

Kupanga pyridine

Pyridine inapezeka ngati mankhwala opangidwa ndi mafuta a malasha kapena kuchotsedwa ku malasha. Njirayi inali yopanda ntchito komanso yogwiritsira ntchito: phula la malasha lili pafupi ndi 0.1 peresenti pyridine, moteronso kuyeretsedwa kwa magawo ambiri kunkafunika, komwe kunachepetsanso zotsatira. Masiku ano, pyridine yambiri imagwiritsidwa ntchito pogwiritsa ntchito mayina angapo, ndipo zofala kwambiri zafotokozedwa apa.

Pyridine Synthesis kupyolera mwa Bohlmann-Rahtz

Pyridine Synthesis kupyolera mwa Bohlmann-Rahtz amalola mzere wa mapiritsi amalowa m'malo mwazikulu ziwiri. Kutsekemera kwa enamine pogwiritsa ntchito ethynylketones kumayambitsa pakatikati a aminodiene omwe, atatha kutentha kwa dzuwa, amapanga cyclodehydration kuti apange pyridines 2,3,6-trisubstituted pyridines.

Pyridine Synthesis kudzera mu njira ya Bohlmann-Rahtz

Njirayi ikugwirizana ndi wotchuka wa Hantzsch Dihydropyridine Synthesis kumenemu situ-generation enamine ndi zinyama zimapanga dihydropyridines. Ngakhale Bohlmann-Rahtz Synthesis ndi yodalirika kwambiri, kuyeretsedwa kwa kutentha kwapakati ndi kutentha kwakukulu kumafunikira kuti cyclodehydration ndizovuta zomwe zakhala zopanda ntchito. Zambiri mwa zovuta zagonjetsedwa, zomwe zimapangitsa Bohlmann-Rahtz Synthesis kukhala ofunika kwambiri mapiritsidi m'badwo.

Ngakhale kuti palibe kafukufuku wamakono omwe wapangidwa, omangamanga angadziŵike ndi H-NMR. Izi zikuwonetsa kuti chogulitsa chachikulu choyamba cha Michael Addition ndi puloteni yotsatila ikhoza kukhala 2Z-4E-heptadien-6-imodzi yomwe imachotsedwa ndi kuyeretsedwa kupyolera mu chromatography ya column.

Choncho, kutentha kwakukulu kwambiri kwa kutentha kwa madzi kumakhala kofunikira kuti tithandize Z/E mausomerizations omwe ali chofunika kwambiri kwa heteroannelation.

Njira zingapo zomwe zimapangitsa kuti maselo a tetra ndi mapiritsi amtundu umodzi asinthidwe posachedwapa. M'malo mogwiritsa ntchito butynone monga gawo lapansi, Bagley anayesa solvents zosiyanasiyana kuti asinthe kutsika kosasinthasintha komanso kocheperako 4- (trimethylsilyl) koma-3-yn-2-imodzi. Izo zinawonetseredwa kuti DMSO ndi EtOH okha ndizo zowonongeka bwino. EtOH imavomerezedwa kukhala polar ndi protic zosungunula ndi DMSO monga polar aprotic zosungunulira. Muzigawo ziwirizi, protodesilylation zinachitika pokhapokha. Bagley adasonyezanso kuti asidi catalysis amalola kuti mpweya uzikhalabe pansi.

Acid catalysis imathandizanso kuwonjezera pa conjugate. Mitundu yambiri ya enamine inagwiritsidwa ntchito ndi ethynyl ketoni mu (5: 1) kusakaniza kwa asidi acid ndi toluene kukwaniritsa mapuloteni opangidwira ntchito pamtunda umodzi mu zokolola zabwino.

Pambuyo pa kupambana kwa Brønstedt asidi catalysis, katswiri wamaphunziro anafufuza kuti akwanitse Lewis asidi othandizira. Malo abwino kwambiri Amagwiritsa ntchito makumi awiri mol% ytterbium triflate kapena fifteen mol% zinc bromide mu refluxing toluene. Ngakhale kuti kachitidwe kafukufuku sikanatheke, tingaganize kuti kugwirizana kwa chothandizira kumayendetsa kayendedwe kake, Michael Addition, ndi isomerization.

Zovutazo ndizochepa zofanana ndi magawo omwe ali ndi asidi. Mwachitsanzo, asidi-omwe amachititsa kuti mavitaminiwa asokonezeke amachitika ndi cyano komanso tert-butylester monga magulu ochotsera magetsi. Njira ina yofatsa ndiyo kugwiritsa ntchito Amberlyst-15 ion kusinthanitsa reagent yomwe imalekerera tert-kugwiritsa ntchito.

Popeza kuti ma enamine sapezeka mosavuta, komanso kuti zipangizo zowonjezereka zikhale bwino, zotsatira za 3 zimagwiritsidwa ntchito pogwiritsa ntchito ammonum acetate monga magwero a amino gulu. Mu njirayi yothandiza, enamine imapangidwa mu situ zomwe zimachita ndi alkynone alipo.

Muyeso yoyamba, ZnBr2 ndipo AcOH ankagwiritsidwa ntchito monga mankhwala othandizira kuti ayambe kusungunuka. Komabe, zakhala zatsimikiziridwa kuti magawo omwe amadziwika ndi asidi nthawi zonse amatenga malo ofatsa ndi EtOH monga zosungunulira.

Chichibabin Synthesis

Chichibabin pyridine kaphatikizidwe kanali koyamba ku 1924 ndipo idakali ntchito yaikulu mu makampani a mankhwala. Imeneyi imapangidwira, yomwe imaphatikizapo kuchepa kwa aldehydes, ketoni, α, β-unsaturated carbonyl mankhwala. Komanso, mawonekedwe onsewa angaphatikizepo kuphatikiza kwa mankhwala omwe ali pamwambawa ndi ammonia woyera kapena omwe amachokera.

Kupanga Pyridine

Kuthamanga kwa formaldehyde ndi acetaldehyde

Mitundu yamakono ndi acetaldehyde ndiwo makamaka magwero a pyridine osasinthidwa. Osachepera, amakhala okwera mtengo ndipo amapezeka mosavuta.

  1. Njira yoyamba ikuphatikizapo kupanga acrolein kuchokera formaldehyde ndi acetaldehyde kupyolera mu Knoevenagel condensation.
  2. Chotsitsa chimachotsedwa ku acrolein ndi acetaldehyde ndi ammonia, kupanga dihydropyridine.
  3. Chomaliza ndi njira yokhudzana ndi okosijeni ndi chothandizira chokhazikika kuti apereke pyridine.
  4. Zomwe tazitchula pamwambazi zimagwiritsidwa ntchito mu gazi gawo ndi kutentha kwa 400-450 ° C. Chipangidwecho chimapangidwa ndi pyridine, picoline kapena mopangidwa ndi methylated pyridines, ndi lutidine. Komabe, zolembazo zimagwiritsidwa ntchito ndi chothandizira chomwe chimagwiritsidwa ntchito komanso pamlingo wina, zimasiyana ndi zofuna za wopanga. Kawirikawiri, chothandizira ndi kusintha zitsulo mchere. Zowonjezeka kwambiri ndi manganese (II) fluoride kapena cadmium (II) fluoride, ngakhale kuti thallium ndi cobalt mankhwala akhoza kukhala njira zina.
  5. Pyridine imapezedwanso kuchokera ku zinthu zomwe zimagwiritsidwa ntchito m'njira zosiyanasiyana. Chiwerengero chachikulu cha Chichibabin pyridine kaphatikizidwe ndi zochepa zokolola, kutembenuza pafupifupi 20% ya mankhwala otsirizira. Pa chifukwa ichi, mitundu yosadziwika ya chigawo ichi ndi yochepa kwambiri.

Bönnemann cyclization

Bönnemann cyclization ndi mapangidwe a trimer kuchokera kuphatikiza magawo awiri a acetylene molekyulu ndi gawo la nitrile. Kwenikweni, ndondomekoyi ndi kusinthidwa kwa Reppe kaphatikizidwe.

Makinawa amathandizidwa ndi kutentha kuchokera kutentha kwapamwamba ndi kupanikizika kapena kupyolera muzithunzithunzi zopangidwa ndi zithunzi. Poyengedwa ndi kuwala, Bönnemann cyclization imafuna CoCp2 (cyclopentadienyl, 1,5-cyclooctadiene) kuti akhale ngati chothandizira.

Njira imeneyi ikhoza kupanga mapulogalamu a pyridine malinga ndi mankhwala omwe amagwiritsidwa ntchito. Mwachitsanzo, acetonitrile idzapereka 2-methylpyridine, yomwe ikhoza kukhala dealkylation kuti ipange pyridine.

Njira zina

Kröhnke pyridine kaphatikizidwe

Njira imeneyi imagwiritsa ntchito pyridine ngati reagent, ngakhale kuti sichidzaphatikizidwa pamapeto pake. Mosiyana ndi zimenezo, zomwe zidzachititse zimapanga ma pyridines m'malo mwake.

Mukayankhidwa ndi α-bromoesters, pyridine idzachita momwe Michael amachitira ndi omwe alibe unsaturated carbonyls kuti apange substriduted pyridine ndi pyridium bromide. Zomwe zimachitidwazo zimadwala ndi ammonia acetate mkati mwa 20-100 ° C.

Kukonzanso kwa Ciamician-Dennstedt

Izi zikuphatikizapo kukula kwa pyrrole ndi dichlorocarbene kupanga 3-chloropyridine.

Gattermann-Skita kaphatikizidwe

Pochita izi, mchere wamchere umayendetsedwa ndi dichloromethylamine pamaso pa maziko.

Boger pyridine kaphatikizidwe

Zotsatira za mapiritsidi

Zotsatira zotsatirazi zikhoza kunenedweratu za pyridines kuchokera kumagetsi awo:

  1. The heteroatom imapangitsa pyridines kusagwira ntchito mosavuta kumagetsi opangidwa ndi mafuta onunkhira opangidwira. Mosiyana ndi zimenezi, mapirini amatha kuwonongeka. Mapiriniini amachitapo kanthu pochita m'malo mwa electrophilic (SEAr) mobwerezabwereza koma m'malo mwachitsulo (SNAr) mosavuta kuposa benzene.
  2. Kuwombera kwa electrophilic reagents makamaka pa Natom ndi pa bC-atomu, pamene nucleophilic reagents amakonda a-ndi cC-atomu.

Kuwonjezera pa Electrophilic pa Nitrogeni

Muzochita zomwe zimaphatikizapo kupanga mapangidwe apamtima pogwiritsira ntchito magulu awiri a electron pa nitrojeni, monga protonation ndi quaternization, mapirini amadziwika ngati aliphatic chapamwamba kapena zonunkhira amines.

Pamene pyridine imakhala ngati maziko kapena nucleophile, imapanga pyridinium cation yomwe sextet yamoto imasungidwa, ndipo nayitrogeni imalandira ndalama zabwino.

Kutsindikiza pa Mavitrogeni

Pyridines amapanga crystalline, kawirikawiri yochuluka, salt ndi protic acid.

Kuthamangitsidwa pa nitrogeni

Izi zimapezeka mosavuta ndi mapuloteni ndi nitronium salt, monga nitronium tetrafluoroborate. Ma protic azrating agents monga nitric acid, ndithudi, amatsogoleredwa ku N-protonation.

Acylation pa nitrogen

Mankhwala a ma acid ndi arylsulfonic acids amachita mofulumira ndi pyridines yopanga 1-acyl- ndi 1- arylsulfonylpyridinium salt mu njira.

Alkyl halides ndi sulphate zimamveka mosavuta ndi pyridines yopereka quaternary salridinium salt.

Mapulogalamu Achidule

Mosiyana ndi benzene, mawonekedwe ambiri opangidwa ndi nucleophilic angapangidwe bwino ndi motsimikizika ndi pyridine. Chifukwa chakuti mpheteyi imakhala ndi mphamvu yochepa ya electron ya maatomu a carbon. Kuchita izi kumaphatikizapo kuchotseratu ndi kuchotsedwa kwa hydride ion ndi kuwonjezera kuwonjezera kuti mupeze kapangidwe ka aryne ndipo nthawi zambiri mupitirize ku 2- kapena 4-malo.

Pyridine yekha sungathe kupanga mapangidwe angapo opatsirana pogwiritsa ntchito nucleophilic. Komabe, kusintha kwa pyridine ndi mabromine, zidutswa za sulfonic asidi, chlorini, ndi fluorine zingayambitse gulu lochoka. Mapangidwe a organolithium mankhwala akhoza kubwezedwa kuchokera ku gulu lopanda bwino la fluorine. Pakadwala kwambiri, nucleophilic imatha kuchita ndi alkoxides, thiolates, amines, ndi ammonia mankhwala.

Ndi ochepa heterocyclic Zomwe zimachitika zingatheke chifukwa chogwiritsa ntchito gulu losauka monga hydride ion. Zotsatira za Pyridine pa 2-malo angapezeke kudzera mu Chichibabin. 2-aminopyridine ikhoza kupitilira pamene sodium amide imagwiritsidwa ntchito monga nucleophile. Molekyujeni wa haidrojeni imapangidwa pamene mapulotoni a gulu la amino akuphatikiza ndi hydride ion.

Mofanana ndi benzene, mapiritsidi mapepala monga heteroaryne amatha kupezeka mmalo mwake m'malo mwa nucleophilic m'malo mwa pyridine. Kugwiritsa ntchito zamchere zamchere monga sodium ndi potaziyamu tert-butoxide kungathandize kuthetsa zowonjezera zowonjezera pirinini pamene mukugwiritsa ntchito ufulu kuchoka pagulu. Pambuyo pa kukhazikitsidwa kwa nucleophile ku mgwirizano katatu, umachepetsanso chisankho ndipo imatsogolera kupanga mapangidwe omwe ali ndi adducts awiri.

Electrophilic Substitutions

Mitundu yambiri ya pyridine yokhala ndi electrophilic ingathe kupitirira mpaka pena kapena musapitirire kwathunthu. Kumbali inayi, chiwalo cha heteroaromatic chikhoza kupititsidwa mwa kugwiritsidwa ntchito kwapiritsi ya electron. Mafuta a Friedel-Crafts (acylation) ndi chitsanzo cha alkylations ndi acylations. Mbaliyi imalephera kupangira pyridine chifukwa izi zimawonjezera kuwonjezera kwa atomu ya nayitrogeni. Zomwe zimaloweza m'malo mwake zimachitika makamaka ku malo atatu omwe ndi imodzi mwa maatomu a mpweya okwera ma electron omwe ali mu mphete zomwe zimapangitsa kuti zikhale zowonjezereka.

Maonekedwe a Pyridine N-Oxide

Mitundu ya electrophilic ingayambitse kusintha kwa malo a pyridine pa 2- kapena 4-malo chifukwa chotsutsana ndi machitidwe ovuta. Komabe, njira zowonetsera zingagwiritsidwe ntchito pamene mukupanga electrophilic m'malo mwa pyridine N-oxide. Pambuyo pake amatsatiridwa ndi atomu ya nitrogeni. Choncho, kutsekula kwa oxygen kumadziwika kuti kuchepetsa kuchulukitsa kwa nitrojeni ndikukweza m'malo a 2-malo ndi 4-carbon carroons.

Mavitamini a divalent sulfure kapena phosphorous ochepa omwe amadziwika kuti ali okosijeni mosavuta makamaka amagwiritsidwa ntchito kuchotsa atomu ya oksijeni. Triphenylphosphine oxide ndi kachulukidwe kamene kamapangidwa pambuyo poyipitsidwa ndi rethasthenyl ya Triphenylphosphine. Ndilo reagent ina yomwe ingagwiritsidwe ntchito kuchotsa atomu ya oksijeni kuchokera ku chinthu china. Zomwe zili pansipa zikufotokozera momwe magetsi ambiri amagwiritsira ntchito pyridine.

Pofuna pyridine nitration amafuna zinthu zina zovuta, ndipo kawirikawiri zimakhala zochepa. Zimene zimachitika m'thupi la pentixide ndi pyridine pamaso pa sodium zimatha kupanga mapangidwe a 3-nitropyridine. Zomwe zimachokera ku pyridine zimapezeka kudzera mu nitration ya nitronium tetrafluoroborate (NO2BF4) posankha atomu ya nayitrogeni mofulumira komanso pamagetsi. Kuphatikiza kwa mankhwala awiri a 6-dibromo pyridine kungachititse mapangidwe a 3-nitropyridine atachotsedwa maatomu a bromine.

Kutsimikiza kwachindunji kumawoneka ngati kosavuta kuposa kulumidwa kwachindunji kwa pyridine. Kutentha kwa pyridine ku 320 ° C kungapangitse pyridine-3-sulfonic asidi mofulumira kusiyana ndi otentha sulfuric acid pa kutentha komweku. Kuwonjezera kwa sulfur element ku atomu ya nayitrogeni ikhoza kupezeka poyambitsa gulu la SO3 pamaso pa mercury (II) sulphate yomwe imakhala chothandizira.

Kukonzekera molunjika ndi bromination kungapitirize mosiyana kwambiri ndi nitration ndi sulfonation. 3-bromopyridine ikhoza kupezeka mwa kuyang'ana kwa bromine ya maselo mu sulfuric acid pa 130 ° C ndi pyridine. Pa chlorination, zotsatira za 3-chloropyridine zikhoza kukhala zochepa pamaso pa aluminium chloride zomwe zimathandiza kwambiri pa 100 ° C. Kuyankha molunjika kwa halogen ndi palladium (II) kungayambitse onse 2-bromopyridine ndi 2-chloropyridine.

Mapulogalamu a Pyridine

Chimodzi mwa zipangizo zomwe zimakhala zofunikira kwambiri ku chemical factories ndi pyridine. Mu 1989, chiwerengero chonse cha pyridine padziko lonse chinali ma 26K tonnes. Malinga ndi 1999, 11 kuchokera ku 25 yayikulu yopanga zojambula zozungulira malo inali ku Ulaya. Ambiri opanga pyridine ankaphatikizapo Koei Chemical, Imperial Chemical Industries, ndi Evonik Industries.

Kumayambiriro kwa 2000s, kupanga pyridine kunakula ndi chigawo chachikulu. Mwachitsanzo, dziko la China lokha limagwiritsa ntchito mphamvu zamtundu wa 30,000. Masiku ano, mgwirizanowu pakati pa US ndi China umayambitsa kupanga kwapamwamba kwambiri pa dziko lapansi.

Mankhwala osokoneza bongo

Pyridine imagwiritsiridwa ntchito kwambiri monga chithunzithunzi cha mankhwala awiri a herbicides diquat ndi paraquat. Pokonzekera mapiritsi a pyrithione, pyridine amagwiritsidwa ntchito ngati chigawo chachikulu.

Zomwe zimachitika pakati pa Zincke ndi pyridine zimabweretsa kupanga mankhwala awiri - laurylpyridinium ndi cetylpyridinium. Chifukwa cha mankhwala awo ophera tizilombo toyambitsa matenda, timagulu timene timagwiritsa ntchito mankhwalawa timaphatikizapo mankhwala opangira mano ndi pakamwa.

Kuukira kwa alkylating agent kwa pyridine kumabweretsa amchere a N-alkylpyridinium, cetylpyridinium chloride kukhala chitsanzo.

Paraquat Synthesis

Solvent

Ntchito ina yomwe pyridine imagwiritsiridwa ntchito ndi knoevenagel condensations, yomwe imagwiritsidwa ntchito ngati gawo lokhazikika, lokha, komanso lokhazikika. Pyridine makamaka ndi yabwino kwambiri kwa dehalogenation, komwe imakhala ngati maziko a kuwonongeka pamene akugwiritsira ntchito hydrogen halide kupanga mchere wa pyridinium.

Muziyandikana ndi zowoneka, Pyridine amachititsa kuti anhydride kapena carboxylic acid halides. Zomwe zimagwira ntchito kwambiri ndi 4- (1-pyrrolidinyl) pyridine ndi 4-dimethylaminopyridine (DMAP), zomwe zimachokera ku pyridine. Pochita zozizwitsa, Pyridine amagwiritsidwa ntchito ngati maziko.

Mapangidwe a pyridinium kupyolera mu kuwonongedwa kwa pyridine

Pyridine ndi chinthu chofunika kwambiri mu makina ovala nsalu. Kuwonjezera pa kugwiritsidwa ntchito monga zosungunulira popanga mphira ndi dyes, zimagwiritsidwanso ntchito kupititsa patsogolo mphamvu ya pathotoni.

Boma la US Food and Drug Administration limavomereza kuwonjezera kwa pyridine pangТono kakang'ono ku zakudya kuti awapatse chisangalalo chowawa.

Mu njira zothetsera mavuto, kudziwika kwa pyridine kuli pafupi 1-3 mmol·LL-1 (79-237 mg · L-1). Kukhala maziko, pyridine angagwiritsidwe ntchito ngati Karl Fischer reagent. Komabe, imidazole nthawi zambiri amagwiritsidwa ntchito monga choloweza m'malo mwa pyridine monga imidazole imakhala ndi fungo lokoma.

Kukonzekera kwa Piperidine

Pyridine hydrogenation ndi catalyst ya ruthenium-, cobalt-, kapena nickel pamatentha otentha amachititsa kupanga piperidine. Ichi ndi chofunikira kwambiri cha mimba ya nayitrogen yomwe ndi malo ofunika kwambiri.

Reagents Specialty Chochokera Pyridine

Mu 1975, William Suggs ndi James Corey anayamba pyridinium chlorochromate. Amagwiritsidwa ntchito kuti oxidize zakumwa zapakati ku ketoni ndi zakumwa zapadera kwa aldehydes. Pyridinium chlorochromate nthawi zambiri amapangidwa pamene pyridine yowonjezeredwa ku yankho la hydrochloric ndi chromic acid.

C5H5N + HCl + CrO3 → [C5H5NH] [CrO3Cl]

Ndi chromyl chloride (CrO2Cl2) pokhala khansa, njira ina iyenera kuyendetsedwa. Mmodzi wa iwo ndigwiritsire ntchito pyridinium chloride kuti awononge chromium (VI) oksididi.

[C5H5NH+] Cl- + CrO3 → [C5H5NH] [CrO3Cl]

Reactant ya Sarret (yovuta kwambiri ya chromium (VI) oxide ndi ma pyterine heterocycle mu pyridine), pyridinium chlorochromate (PCC), Cornforth reagent (pyridinium dichromate, PDC), ndi Collins reagent (zovuta za chromium (VI) oxidi ndi pyridine heterocycle mu dichloromethane) ndi ofanana ndi chromium-pyridine mankhwala. Amagwiritsidwanso ntchito kuti azitayidwa, monga kutembenuka kwa zakumwa zapakati ndi zapadera kwa ketoni.

Ma reagents a Sarret ndi Collins sizongokhalira kukonzekera, koma ndizoopsa. Zimakhala zochepa kwambiri ndipo zimatha kunyalanyaza panthawi yokonzekera. Chifukwa chake, ntchito ya PDC ndi PCC inalimbikitsidwa. Ngakhale kuti ma reagents awiriwa amagwiritsidwa ntchito kwambiri mu 70s ndi 80s, iwo sagwiritsidwa ntchito mobwerezabwereza chifukwa cha poizoni wawo ndipo amatsimikizira kuti matendawa ndi oopsa.

Kapangidwe kake ka Crabtree

Pogwirizanitsa mapangidwe, pyridine amagwiritsidwa ntchito kwambiri monga ligand. Zimachokera, monga momwe zimayambira 2,2'-bipyridine, yomwe ili ndi mamolekiti a 2 pyridine omwe amamangidwa ndi mgwirizano umodzi, ndi terpyridine, molekyumu ya mphete za 3 pyridine zogwirizana pamodzi.

Chitsulo cholimba cha Lewis chingagwiritsidwe ntchito monga mmalo mwa pyridine ligand yomwe ili gawo la chitsulo chovuta. Chikhalidwe ichi chikugwiritsidwa ntchito mu catalysis ya polymerization ndi machenjezo a hydrogenation, pogwiritsa ntchito, mwachitsanzo, Carabtree chothandizira. The pyridine Lingard yomwe imaloweza mmalo mwazobwezeretsedwa kubwereranso itatha.

Zothandizira

Nomenclature ya Organic Chemistry: Mayankho a IUPAC ndi Mayina Amene Amapatsidwa 2013 (Buluu la Buluu). Cambridge: Royal Society ya Chemistry. 2014. p. 141.

Anderson, T. (1851). "Ueber ndi Producte der trocknen Destillation thierischer Materien" [Pamakina opangidwa ndi zowonongeka za zinyama]. Annalen der Chemie und Pharmacie. 80: 44.

Sherman, AR (2004). "Pyridine". Pa Paquette, L. Encyclopedia ya Reagents kwa Organic Synthesis. e-EROS (Encyclopedia of Reagents kwa Organic Synthesis). New York: J. Wiley & Ana.

Behr, A. (2008). Katalyse wamtundu watsopano. Weinheim: Wiley-VCH. p. 722.