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Duk Kuna Bukatar Sanin Pyridines

Duk Kuna Bukatar Sanin Pyridines

Duk Kuna Bukata Ya San Game Pyridines

Pyridine shine ainihin heterocyclic fili na irin azine. An samu pyridine daga benzene ta hanyar maye gurbin kungiyar ta CH ta hanyar N-atom. Tsarin Pyridine yayi daidai da tsarin benzene, saboda ana danganta shi ta hanyar maye gurbin CH ta hanyar N. Babban bambance-bambance sun haɗa da:

  1. Fita daga sashin yanayi na yau da kullum na yau da kullum saboda kasancewar kwayar hetero, don ƙayyade, ƙananan shaidu na nitrogen-carbon,
  2. Sauyawa na atomatik a cikin motar motar tare da nau'in wutar lantarki mara kyau, kamar a cikin motar zobe, wanda yake a cikin mabudi na sp2, kuma ba shi da wani ɓangare na p-electron. Wannan nitrogen din din guda daya wanda ke da alhakin kayan asali na pyridines,
  3. Ƙaƙƙarfan dindindin mai karfi wanda aka gano zuwa gagarumin wutar lantarki ta atomatik wanda aka kwatanta da carbon atom.

Ƙungiyar tsararraki tana aukuwa a wasu magunguna masu mahimmanci, ciki har da bitamin dacin, pyridoxine, da azines.

Wani masanin kiristancin Scotland, Thomas Anderson ya ƙirƙira pyridine a cikin 1849 a matsayin daya daga cikin mahadi wadanda suka zama man fetur. Bayan shekaru biyu, Anderson ya sami tsabta ta tsabta ta hanyar rarraba kashi na man fetur. Yana da mummunan flammable, marar lahani, ruwa mai narkewa, ruwa mai ruɗɗa mai rauni tare da ƙarancin bambanci, ƙanshi kamar kifi.

Pyridine ana amfani dashi a matsayin mai ƙaddara zuwa pharmaceuticals da agrochemicals kuma yana da mahimmancin haɗari da sauran ƙarfi. Za'a iya ƙara pyridine zuwa ethanol idan kana so ka sanya shi mara amfani ga amfanin mutum. Har ila yau, zane a cikin samar da kwayoyi masu magungunan antihistaminic mepyramine da tripelennamine, in vitro kira na DNA, a cikin samar da sulfapyridine (maganin maganin cututtukan cututtukan cututtuka da cututtuka na kwayan cuta), da bactericides, herbicides, and water repellents.

Yawancin maharan sunadarai, ko da yake ba'a samar da su daga pyridine ba, sun ƙunshi tsarin zobe. Wadannan mahaukaci sun hada da bitamin B kamar pyridoxine da niacin, nicotine, kayan da ke dauke da nitrogen, da magungunan maganin tarin fuka da ake kira isoniazid. Pyridine an tsara shi ne a tarihi ta hanyar samar da gashin kwalba da kuma tarin kwalba. Kodayake, buƙatar samaniya na pyridine ya haifar da ci gaba da hanyoyin bunkasa tattalin arziki daga ammoniya da acetaldehyde, kuma an samar da nauyin 20,000 ton a kowace shekara a duniya.

Sakamakon kira na pyridine

Sunan tsarin pyridine, kamar yadda Hantzsch-Widman nomenclature wanda IUPAC ya nuna, shine azine. Amma sunayen sunadaran don magunguna masu amfani suna da wuya; maimakon haka, ƙididdigar ƙwayoyin hanyoyi suna biyo bayan sunaye sunaye. IUPAC ba ƙarfafa amfani da azine lokacin da ake magana da shi pyridine.

Ƙididdigar mahaifa a azine ya fara ne a nitrogen. An rarraba matsayi ta hanyar haruffa na haruffa na Helenanci (α-γ) da kuma maye gurbin nomenclature wanda ya saba da tsarin tsarin homoaromatic (para ortho, makasudin,) ana amfani dashi wani lokaci. A nan α, β da γ suna nufin wurare biyu, uku, da hudu, bi da bi.

Sunan tsarin da aka gano na pyridine shine pyridinyl, inda lamba ya wuce matsayin da aka sanya ta atomatik da aka ƙaddara ta lamba. Amma sunan tarihi pyridyl an bayar da shawarar ta IUPAC kuma an yi amfani dashi a madadin sunan tsarin. Abinda ya samo asali ne ta hanyar bita mai amfani da na'urar nitrogen shine aka sani da shi pyridinium.

4-bromopyridine

2,2'-bipyridine

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

Ainihin nauyin pyridinium cation

Samar da pyridine

An samo Pyridine a matsayin hanyar samar da kwalba ko cire daga tashar kwal. Wannan hanya ba ta da kyau kuma aiki-cinyewa: tarin kwalba yana kusa da 0.1 bisa dari na pyridine, kuma saboda haka ana bukatar tsarkakewa da yawa, wanda ya rage yawan kayan aiki. Yau, yawancin pyridine ana sarrafa su ta hanyar amfani da wasu nau'in halayen halayen, kuma mafi yawan waɗanda aka fi kowa suna tattauna a nan kasa.

Pyridine kira ta hanyar Bohlmann-Rahtz

Hadin Pyridine ta hanyar Bohlmann-Rahtz yana ba da damar tsara pyridines a manyan matakai biyu. Jigilar katako ta hanyar amfani da ethynylketones yana haifar da tsaka-tsakin aminodiene wanda, bayan da isomerization ya haifar da zafi, ya shawo cyclodehydration don samar da pyridines 2,3,6-trisubstituted.

Hidimar Pyridine ta hanyar hanyar Bohlmann-Rahtz

Hanyar yana da alaka da Hantzsch Dihydropyridine Synthesis inda akea wuri-arancin da ake ciki da kuma jinsin halitta samar da dihydropyridines. Kodayake Bohlmann-Rahtz kira yana da kyau sosai, tsarkakewa na matsakaici da kuma yanayin zafi mai tsanani wanda ake buƙata don haɓakar cyclodehydration kalubale ne wanda ya iyakance amfaninta. Yawancin kalubale sun rinjaye, sautin Bohlmann-Rahtz ya fi muhimmanci a cikin pyridines tsara.

Ko da yake ba a gudanar da binciken bincike na injiniya ba, za a iya bayyana tsaka-tsaki tsakanin H-NMR. Wannan ya nuna cewa babban samfurin na farko Michael Addition da kuma hanyar proton na gaba iya zama 2Z-4E-heptadien-6-daya da aka cire da kuma tsarkake ta shafi chromatography.

Saboda haka akwai yanayin zafi mai haɗari mai zurfi don sauƙaƙe Z/E isomerizations wanda shine abin da ake buƙata don haɓakawa.

Yawancin hanyoyin da ke ba da damar yin amfani da tetra da pyridines masu tasowa a cikin tsari guda daya an ci gaba kwanan nan. Maimakon yin amfani da butynone a matsayin madauri, Bagley yayi gwajin gwaje-gwaje daban-daban don canzawa maras amfani da 4- (trimethylsilyl) amma-3-yn-2-daya. An nuna cewa kawai DMSO da EtOH su ne mafita masu kyau. Ana nuna darajar yayinda ake amfani da shi a matsayin mai yaduwa da ƙwararru. Vs. DMSO a matsayin ƙananan kwalliya. A cikin wadannan maganin biyu, an yi amfani da ƙarancin hanzari. Bagley ya nuna cewa acid catalysis yana ba da damar cyclodehydration don ci gaba a ƙananan zafin jiki.

Acid catalysis kuma yana ƙarfafa ƙarin haɗin gwiwa. An yi tasiri mai tsabta mai tsabta tare da ethynyl ketones a cikin (5: 1) cakuda acetic acid da ukuene don samar da pyridines masu aiki a mataki daya a cikin kyakkyawan ƙwaya.

Bayan nasarar nasarar Brønstedt acid catalysis, chemist yayi nazarin ikon Lewis acid catalysts. Yanayi mafi kyau Ana amfani da su ashirin mol% ytterbium ko goma sha biyar mol% zinc bromide a cikin refluxing toluene. Ko da yake ba a gudanar da bincike na injiniya ba, zamu iya ɗauka cewa daidaituwa ta hanyar mai haɓaka ya ƙaddamar da ruwan sanyi, Additional Michael, da kuma matakan isomerization.

Rushewar ita ce iyakancewa tareda daidaitattun abubuwa. Alal misali, haɗarin acid-catalyzed decomposition na enamines faruwa da cyano da kuma tert-butylester a matsayin raƙuman ƙungiyoyinsu. Wata hanya mai sauƙi shine aikace-aikace na Amberlyst-15 ion canza musayar abin da ke jurewa tert-butylesters.

Tun da yake baza'a iya samuwa ba, kuma don inganta kayan aikin, ana aiwatar da wani nau'in 3-bangaren da amfani da ammonium acetate a matsayin tushen asalin amino. A cikin wannan hanya mai inganci, ana haifar da bayani a wuri wanda ya haɓaka da alkynone ba.

A cikin gwajin farko, ZnBr2 kuma AcOH an yi amfani da shi azaman karin haɗari tare da toluene kamar sauran ƙarfi. Duk da haka, an riga an nuna cewa acid-sensitive substrates ko da yaushe amsa a cikin m yanayi tare da EtOH a matsayin sauran ƙarfi.

Chichibabin kira

An kira rahoton farko na Chichibabin pyridine a cikin 1924 kuma har yanzu shine babban aikace-aikace a masana'antun sunadarai. Yana da motsi jiki, wanda ya haɗa da nauyin motsa jiki na aldehydes, ketones, α, β-unsaturated carbonyl mahadi. Bugu da ƙari, yawan nau'i na wannan haɗuwa zai haɗa da haɗuwa da samfurorin da aka samo a cikin ammonia mai tsarki ko abubuwan da suka samo.

Darasi na Pyridine

Condensation na formaldehyde da acetaldehyde

Formaldehyde da acetaldehyde sune yafi tushen tushen pyridine. Aƙalla, suna da araha kuma suna iya karuwa.

  1. Mataki na farko ya ƙunshi samuwar acrolein daga formaldehyde da acetaldehyde ta hanyar Knoevenagel sanyaya.
  2. An samo samfurin ƙarshe daga acrolein da acetaldehyde da ammoniya, ta zama dihydropyridine.
  3. Tsarin karshe shine samin maganin maganin shayarwa tare da mai karfi na jihar don samar da pyridine.
  4. An yi wannan aikin a cikin wani lokaci na gas tare da yanayin zafin jiki na 400-450 ° C. Gidan da aka kafa ya ƙunshi pyridine, picoline ko methylated pyridines, da kuma lutidine. Duk da haka, abun da ke ciki shine batun ƙaddamarwa da amfani kuma har zuwa wasu, ya bambanta da bukatun masu sana'a. Yawanci, mai haɓakawa shine gishiri mai sauƙi. Mafi yawan sunadaran ne (II) fluoride ko cadmium (II) fluoride, ko da yake thallium da kuma mahadar cobalt zasu iya zama madadin.
  5. Ana gano adadin pyridine daga samfurori a cikin tsari mai yawa. Mafi yawan iyakokin kira na Chichibabin pyridine shine ƙananan yawan amfanin ƙasa, ana fassara zuwa game da 20% na samfurori na ƙarshe. Saboda wannan dalili, siffofin marasa tsari na wannan fili basu da yawa.

Bönnemann cyclization

Bönnemann cyclization shi ne kafa wani trimer daga hade biyu sassa na acetylene kwayoyin kuma wani ɓangare na nitrile. A gaskiya, tsari shine gyare-gyaren Rabin kira.

Ana amfani da ingancin ta hanyar zafi ko zafi daga yanayin zafi da matsin lamba ko ta hanyar haɗuwa da hoto. Lokacin da haske ya kunna, Bönnemann cyclization na bukatar CoCp2 (cyclopentadienyl, 1,5-cyclooctadiene) don yin haɗari.

Wannan hanya za ta iya samar da jerin sifofin da aka tsara ta pyridine dangane da mahaɗan da ake amfani dashi. Alal misali, acetonitrile zai haifar da 2-methylpyridine, wanda zai iya shawo kan kwayar halitta don samar da pyridine.

Sauran hanyoyin

Harshen Kröhnke pyridine

Wannan hanya tana amfani da pyridine a matsayin mai haɗari, ko da yake ba za a haɗa shi a samfurin ƙarshe ba. Sabanin haka, aikin zai samar da pyridines.

A lokacin da aka amsa tare da mahaukacin kwalliya, pyridine za su dauki nauyin Michael kamar yadda carbonyls basu da shi don samar da pyridine da pyridium bromide. Ana biyan wannan maganin tare da ammonia acetate a cikin 20-100 ° C yanayi mai kyau.

Ciamician-Dennstedt gyarawa

Wannan ya hada da ƙaddamar da pyrrole tare da dichlorocarbene forming 3-chloropyridine.

Gattermann-Skita kira

A cikin wannan yanayin, malonate ester gishiri ya haɓaka da dichloromethylamine a gaban wani tushe.

Boger pyridine kira

Ayyuka na pyridines

Za'a iya kwatanta wadannan halayen nan na pyridines daga tsarin lantarki:

  1. Heteroatom yana sa pyridines ba su da kullun ga tsarin canzawa na electrophilic na al'ada. Hakanan, pyridines suna da saukin kamuwa da harin nucleophilic. Pyridines suna samun karɓan zaɓuɓɓuka na electrophilic (SEAr) fiye da ba tare da haɗuwa ba amma maye gurbin (SNAr) mafi sauki fiye da benzene.
  2. Masu haɗin gwargwadon electrophilic sun kai hari mafi kyau a cikin Natom da kuma a bC-atomes, yayin da masu haɗarin nucleophilic sun fi son a- da cC-atomes.

Ƙarar Electrophilic a Nitrogen

A cikin halayen da ya haɗa da yin amfani da jabu ta hanyar amfani da nau'in lantarki guda ɗaya a cikin kwayar zobe, kamar su protonation da tsaka-tsayi, pyridines suna nuna hali kamar na aliphatic magunguna ko amines aromatic.

Lokacin da pyridine ya haɓaka a matsayin tushe ko wani magungunan kwalliya, shi ya zama cationin pyridinium wanda aka dakatar da shi, kuma nitrogen ta sami takardar shaida mai kyau.

Protonation a Nitrogen

Pyridines samar da crystalline, akai-akai hygroscopic, salts da mafi yawan protic acid.

Nitration a Nitrogen

Wannan yana faruwa ne da sauri ta hanyar maganin pyridines tare da saltson nitronium, irin su nitronium tetrafluoroborate. Masu amfani da hade mai cin hanci kamar nitric acid, ba shakka, kai tsaye ga N-protonation.

Acylation a nitrogen

Acid chlorides da acid arylsulfonic yi sauri tare da pyridines samar da 1-acyl- da 1-arylsulfonylpyridinium salts a cikin bayani.

Alkyl halides da sulfates sunyi sauƙi tare da pyridines suna bada saltsin pyridinium quaternary.

Ƙunƙwasawa na Nucleophilic

Sabanin benzene, yawancin maye gurbin nucleophilic na iya zama da kyau tare da ingantawa ta hanyar pyridine. Domin saboda zobe yana da ƙananan ƙananan lantarki na ƙwayoyin carbon. Wadannan halayen sun haɗa da maye gurbin tare da cirewar jigilar hydride da haɓakawa don samun daidaitattun matakan matsakaici kuma yawanci ci gaba zuwa 2- ko 4-matsayi.

Pyridine kadai ba zai haifar da samuwar sauye-sauyen nucleophilic ba. Duk da haka, gyaran haɓakar pyridine tare da bromine, sulfonesic acid gutsutsure, chlorine, da kuma fluorine zai iya haifar da ƙungiyar barin. Za a iya samo asalin kwayoyin organolithium daga mafi kyawun barin ƙungiya na fure. A matsin lamba, nucleophilic zai iya amsawa tare da alkoxides, magunguna, amines, da ammonia mahadi.

Few heterocyclic halayen zasu iya faruwa saboda amfani da ɓangaren matalauta kamar hydride ion. Abubuwan da za a iya gina pyridine a matsayin 2 za a iya samuwa ta hanyar amsawar Chichibabin. 2-aminopyridine zai iya ci gaba da ci gaba yayin da ake amfani da sodium amide a matsayin mai amfani da shi. An kafa kwayar halittar hydrogen lokacin da protons na amino kungiyar suka hada da hydride ion.

Misali kamar benzene, pyridines za a iya samun tsaka-tsakin yanayi kamar su heteroaryne ta hanyar maye gurbin nucleophilic zuwa pyridine. Yin amfani da alkaline mai karfi irin su sodium da potassium tert-butoxide na iya taimakawa wajen kawar da abubuwan da ke tattare da pyridine lokacin amfani da dama barin kungiyar. Bayan an gabatar da mahalartacciyar zuwa kashi uku, yana rage yawan zaɓin da zai jagoranci gawarwar cakuda wanda yana da addu'o'i guda biyu.

Ƙungiyoyin Electrophilic

Yawancin wakilan lantarki na pyridine zasu iya ci gaba har zuwa wani batu ko ba su ci gaba da gaba ɗaya ba. A wani ɓangaren kuma, za a iya motsa batun haɓaka ta hanyar aiki na bada kyautar lantarki. Friedel-Crafts alkylation (acylation) misali ne na alkylations da acylations. Wannan batu ba zai karbi pyridine ba tun lokacin da ya haifar da adadin nitrogen. Sauran sunaye ne a matsayi uku wanda shine ɗaya daga cikin carbon carbon-rich carbon da ke cikin zobe wanda zai sa ya dace da ƙarin adadin lantarki.

Tsarin Pyridine N-Oxide

Hanyoyin zaɓuɓɓuka na Electrophilic zai iya haifar da sauyawa matsayin matsayi na pyridine a 2- ko 4-matsayi saboda mummunar haɗari σ. Duk da haka, ana iya amfani da hanyoyi gwaji yayin yin gyare-gyaren electrophilic akan N-oxide pyridine. An kuma biyo bayan nitrogen atom deoxygenation. Saboda haka, gabatarwar oxygen an san shi don rage yawan abu a kan nitrogen kuma inganta canzawa a matsayin 2 da 4-matsayin carbons.

Magunguna na sulfur mai yawan sukari ko phosphorus guda ɗaya ana san su da sauƙi a sauyewa saboda haka yafi amfani dasu don cire oxygen atom. Triphenylphosphine oxide ne mai fili wanda aka kafa bayan an cire shi daga tsarin Triphenylphosphine. Yana da wani nau'in hawan gwaiwar da za a iya amfani dasu don kawar da iskar oxygen daga wani abu. Bayanan da ke ƙasa ya kwatanta yadda canzawa na electrophilic talakawa ya haɗu da pyridine.

Daidaita farashin pyridine yana buƙatar matsanancin yanayi, kuma yana da ƙananan ƙwayoyi. Ayyukan dinitrogen pentoxide tare da pyridine a gaban sodium zai iya haifar da samuwar 3-nitropyridine. Za'a iya samuwa abubuwan da ake amfani da su na pyridine ta wurin nitration na nitronium tetrafluoroborate (NO2BF4) ta hanyar ɗaukar atomatik nitrogen a sannu-sannu da kuma na lantarki. Harkokin mahadi biyu na 6-dibromo pyridine zai iya haifar da samuwar 3-nitropyridine bayan an cire bama-bromine.

An yi la'akari da ƙayyadaddun ƙayyadaddun wuri fiye da sulhunin sulfonation na pyridine. Ruwan pyridine a 320 ° C zai iya haifar da pyridine-3-sulfonic acid fiye da tafasa sulfuric acid a yanayin yanayin. Ƙarin sulfur kashi zuwa nitrogen nitrogen za a iya samu ta hanyar amsa ƙungiyar SO3 a gaban mercury (II) sulfate wanda ya zama mai haɗari.

Daidaita gwargwado da bromination na iya ci gaba da sabanin nitration da sulfonation. 3-bromopyridine za'a iya samuwa ta hanyar maganin bromine kwayoyin a sulfuric acid a 130 ° C tare da pyridine. Bayan chlorination, sakamakon 3-chloropyridine zai iya zama low a gaban aluminum chloride wanda yayi a matsayin mai haɗaka a 100 ° C. Hanyar kai tsaye na halogen da palladium (II) na iya haifar da 2-bromopyridine da 2-chloropyridine.

Aikace-aikace na Pyridine

Daya daga cikin kayan da ke da matukar muhimmanci ga masana'antun sinadaran shine pyridine. A 1989, yawan samar da pyridine a dukan duniya shine 26K tonnes. Kamar yadda na 1999, 11 daga 25 manyan wuraren samar da pyridine sun kasance a Turai. Babban magungunan pyridine sun hada da Koei Chemical, Masana'antu na Harkokin Kasuwanci, da kuma Evonik Industries.

A farkon 2000s, samar da pyridine ya karu ta hanyar haɗari mai girma. Alal misali, kasar Sin kadai ta sami damar samar da kayan aikin 30,000 a kowace shekara. A yau, hadin gwiwar tsakanin Amurka da kasar Sin ya haifar da samar da mafi girma a duniya.

magungunan kashe qwari

Pyridine an fi amfani dashi a matsayin mai ƙaddara zuwa biyu da diquat da paraquat herbicides. A cikin shirye-shirye na furotin na tushen pyrithione, an yi amfani da pyridine a matsayin tushen asali.

Aikin tsakanin Zincke da sakamakon pyridine a cikin samar da mahadi biyu - laurylpyridinium da cetylpyridinium. Saboda magungunan maganin antiseptic, an haɗa nau'ikan guda biyu zuwa ga hakori da maganganun maganganu.

Wani harin da wani wakilin alkylating ya kai ga sakamakon pyridine a cikin salts N-alkylpyridinium, cetylpyridinium chloride daya misali.

Alamar Paraquat

Ƙididdiga

Wani aikace-aikacen da ake amfani da pyridine yana cikin raguwa na Knoevenagel, inda aka yi amfani dashi azaman mai sauƙi, polar, da kuma sauran ƙwayoyi. Pyridine yana da mahimmanci na musamman don dehalogenation, inda ya zama tushen tushen kawarwa yayin haɗakar da sakamakon hydrogen halide don samar da gishiri pyridinium.

A cikin acylations da esterifications, Pyridine ta kunna anhydrides ko hamsin carboxylic acid. Har ma mafi aiki a cikin wadannan halayen su ne 4- (1-pyrrolidinyl) pyridine da 4-dimethylaminopyridine (DMAP), waxanda suke da alamun pyridine. A cikin motsin motsi, Pyridine ana amfani dashi a matsayin tushe.

Formation of pyridinium ta hanyar kawar da tare da pyridine

Pyridine ma abu ne mai muhimmanci a cikin masana'antun masana'antu. Bayan an yi amfani da shi a matsayin mai ƙanshi a cikin samar da rubber da dyes, ana amfani da shi don inganta haɗin wayar ta auduga.

Cibiyar Abinci da Drugta ta Amurka ta amince da ƙara yawan pyridine a cikin ƙananan ƙananan abinci don ciyar da su tare da ƙanshi mai zafi.

A cikin mafita, ganowa kofa na pyridine yana kusa da 1-3 mmol·L-1 (79-237 MG · L-1). Da yake zama tushen, za'a iya amfani da pyridine a matsayin Karl Fischer reagent. Duk da haka, ana amfani da imidazole a madadin pyridine kamar yadda (imidazole) yana da wari mai ban sha'awa.

Precursor zuwa Piperidine

Hanyoyin da aka gina tare da ruthenium-, cobalt-, ko kuma mai kwakwalwa na nickel a yanayin zafi masu zafi ya haifar da samar da piperidine. Wannan wata mahimmanci ne mai amfani da kwayar nitrogen wadda ke da mahimmin ginin gine-gine.

Ƙwararren ƙwararru na musamman a kan Pyridine

A cikin 1975, William Suggs da James Corey sun haɓaka pyridinium chlorochromate. An yi amfani da shi don oxidize na biyu na alcohols zuwa ketones da kuma na farko na alcohols zuwa aldehydes. An samo al'adar pyridinium chlorochromate a yayin da aka kara pyridine zuwa mafita na hydrochloric da acid chromic.

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

Tare da chromyl chloride (CrO2Cl2) kasancewa mai cututtuka, dole ne a nemi hanya madaidaiciya. Daya daga cikinsu shine yin amfani da pyridinium chloride don bi da chromium (VI) oxide.

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

Sarret reagent (hadadden ƙwayar chromium (VI) tare da pyridine heterocycle a pyridine), pyridinium chlorochromate (PCC), Gwargwadon Cornforth (pyridinium dichromate, PDC), da kuma gwargwadon ƙwayoyin Collins (hadadden ƙwayar chromium (VI) da pyridine heterocycle a dichloromethane) su ne masu kama da chromium-pyridine. Ana kuma amfani da su don yin amfani da iskar shaka, irin su yin hira da sakandare da kuma na farko na hagu zuwa ketones.

Maganin Sarret da Collins ba kawai ba ne kawai suke shirya ba, amma sun kasance masu haɗari. Su hygroscopic ne kuma suna da sauƙi don yin watsiwa a lokacin shiri. Saboda haka, an yi amfani da PDC da PCC. Duk da yake an yi amfani da su biyu a cikin 70s da 80s, suna da wuya a yi amfani da su a yanzu saboda rashin ciwon haɗari da kuma tabbatar da maganin cututtuka.

Tsarin fasahar Crabtree

A cikin haɓin sunadarai, an yi amfani da pyridine a matsayin ligand. Yana da banbanci, kamar yadda 2,2'-bipyridine ta ƙera, wanda ya ƙunshi kwayoyin 2 pyridine da aka haɗe ta guda ɗaya, da kuma terpyridine, kwayoyin 3 pyridine sun haɗa da juna.

Za a iya amfani da tushe mai zurfi na Lewis a matsayin maye gurbin wata ligandin pyridine wanda ke cikin wani ƙwayar ƙarfe. Wannan halayyar tana amfani da shi a catalysis na haɓaka polymerization da hydrogenation, ta yin amfani da, alal misali, Carabtree ta haɓaka. Aikin da ake kira pyridine Lingard wanda aka maye gurbin a lokacin da aka sake dawowa bayan kammalawa.

References

Ƙididdigar Ƙungiyar Halitta ta Halitta: IUPAC Shawarar da Sunaye Sunan Farfajiya 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. p. 141.

Anderson, T. (1851). "Ueber die Producte der trocknen Destillation thierischer Materien" [A samfurori na distillation bushe na kwayoyin dabbobi]. Annalen der Chemie und Pharmacie. 80: 44.

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

Behr, A. (2008). Angewandte homogene Katalyse. Weinheim: Wiley-VCH. p. 722.