Reactions Ukufakwa: inkcazelo, imizekelo equation

endaweni abaninzi asabela kuvula indlela eya ukulungiselela iikhompawundi ezahlukahlukeneyo ukuba isicelo eluncedo. A indima enkulu kwinzululwazi kwemichiza kunye noshishino anikwe endaweni electrophilic kunye nucleophilic. Organic ezwi, ezi nkqubo kufuneka eziliqela iinkalo ekufuneka kuphawulwe.

Iintlobo ngeentlobo iziganeko imichiza. kufakwe indlela

utshintsho zemichiza ezinxulumene kwinguqu mba, iqela lemisebenzi esemqoka ezahlukeneyo. Ngamana ukuba iziphumo ezahlukeneyo, iziphumo thermal; ezinye iinkqubo uza nakugqiba, ifike kwezinye imichiza kuvuselele. Kancincane agents ukuba Idla ngokwandisa okanye ukunciphisa izinga igcwala. Xa ukuhlelwa ngezenzeko imichiza kwiziphumo zazo zeemviwo zokugqibela ukutsalela ingqalelo umahluko ubunjani kunye neenkcukacha zamanani phakathi reactants kwimveliso. Ezi mpawu zingahlukaniswa iintlobo 7 ekudibaneni kwemichiza, kuquka endaweni, aluhambi ngokwale nkqubo: A-B-C A + C + B. Ukurekhoda lula kwiklasi iphela ngezenzeko wemichiza kunika uluvo leyo ekuthiwa-"umhlaseli phakathi izinto eqala "yamasuntswana substituent kwi-atom reagent, ion iqela olusebenzayo. Ukufaka abasabela ngayo uphawu isinyibiliko hydrocarbon enuka kamnandi.

endaweni yokusabela kwenzeka ngohlobo kabini-exchange: A-B-C + E C + A-B-E. Enye zenyathi - ukubana, umz, ubhedu, intsimbi ukusuka nesisombululo sulphate sobhedu: CuSO ₄ + Fe = FeSO ₄ + Cu. Njengoko "ebelihlasela" Amasuntswana ukwenza athom, ion okanye amaqela ezisebenzayo

endaweni Homolytic (ezinkulu, SR)

Xa indlela ngokupheleleyo isibini komsipha covalent electron kuqhelekile ukuba izinto ezahlukeneyo iya kulingana isasazwe phakathi "ngamaqhekeza" kwemolekyuli. Formation of radicals simahla. Le Ukuzinziswa yamasuntswana ezingazinzanga leyo kwenzeka ngenxa yokusabela ezilandelayo. Umzekelo, ekulungiseleleni-methane ukusuka methane ukuvelisa radicals ezamahala ababandakanyekayo indlela endaweni: CH ₄ CH ₃ • + • H; CH ₃ • + • CH ₃ → C2H5; H • + • H → H2. Homolytic bond cleavage kwi indlela yokusebenza ye endaweni na uphawu alkanes, basabela Ungumlinganiswa chain. Ezi athom methane H zinokuthi ngokulandelelana indawo chlorine. Ngokufanayo azithethelele bromine, iodine kodwa akakwazi ukubuyisela ngqo alkanes hydrogen, fluorine Lize ngamandla kakhulu nabo.

bond Heterolytic indlela cleavage

Xa indlela ion flow reactions endaweni, electron ukuba edyokhweni isasazwe phakathi amasuntswana abasandula saphakama. Laba yokucheba elektroni usinika yonke indlela ukuya kwenye "amaqhekeza", amaxesha amaninzi, ukuze iqabane unxibelelwano, icala elo lisisiqalo ingxinano ezigxekayo molecule ezibandayo. Xa kufakwe esisabela ngayo iquka indlela ukuyilwa CH imethyl utywala ₃ OH. In brommetane Umsantsa CH3Br molecule isimilo heterolytic, amasuntswana ebizwayo uzinzile. Methyl izuza isimangalo ezintle, kunye bromo - ezingalunganga: CH ₃ Br → CH ₃ ^{+ +} Br ^-; NaOH → Na ^{+ +} WO ^-; CH ₃ ^{+ +} KOWU ^- → CH ₃ OH; Na ^{+ +} Br ^- ↔ NaBr.

Electrophiles kunye nucleophiles

Amasuntswana ukuba abanakho electron kwaye akakholeki kum, zibizwa ngokuba "electrophiles." Ezi athom carbon kwii kunye halogens ku haloalkanes. Nucleophiles babe electron ezixineneyo, ukuba "amaxhoba" ye iperi electron ukudala ibhondi covalent. Ukufaka abasabela izityholo izityebi embi bahlaselwa nucleophiles electrophiles, intswelo electron. Le meko linxulunyaniswa intshukumo-athom okanye ezinye amasuntswana - eshiya qela. Olunye uhlobo yendlela endaweni - lokuhlasela nucleophile electrophile. Ngamanye amaxesha kunzima ukwahlula phakathi iinkqubo ezimbini, wabhekisela ukutshintshwa omnye okanye olunye uhlobo, ngokuba kunzima ukuba ucacise ngqo uhlobo molecule - zeendawana, yaye leyo - reagent. Ngokuqhelekileyo kwiimeko ezinjalo, le miba ilandelayo ingqwalasela:

• uhlobo iqela ushiya;
• i reactivity le nucleophile;
• uhlobo isinyibilikisi;
• i alkyl isabelo eso sakhiwo.

endaweni Nucleophilic (SN)

Xa inkqubo yentsebenziswano kwi molecule eziphilayo soloko nokwehlukana. Xa zibalo kwentlawulo buso entle okanye embi iboniswe unobumba we-alfabhethi zamaGrike. unxibelelwano nokwehlukana lunika yohlobo komsipha kunye nokuziphatha kwixesha elizayo "ngamaqhekeza" kwemolekyuli. Umzekelo, i-atom kwekhabhoni iodomethane na isimangalo buso entle, yinto iziko electrophilic. Itsala lo dipole emanzini, apho oxygen une agqithisile electron. Xa abasabela ngayo electrophile kunye nucleophile ezikhandelwa methanol: CH ₃ Mna + H ₂ → CH ₃ KOWU + HI. reactions endaweni nucleophilic uthathe indawo inxaxheba kwaku- kakubi ityala okanye molecule ukuba electron isibini simahla, engaquki inxaxheba ekudalweni ibhondi wemichiza. inxaxheba iodomethane kwi-SN _2-asabela ngenxa ngokuphandle yayo ehlasela nucleophilic kunye iodine ukuhamba.

endaweni Electrophilic (SE)

Le molecule eziphilayo ukuze iziko langoku nucleophilic, nto leyo luphawulwa agqithisile electron mninzi. Idityaniswe ukunqongophala izityholo ezimbi reagent electrophilic. amasuntswana ezinjalo athom ukuba molecule Orbital simahla kunye iinxalenye nokuphungulwa electron mninzi. I- sodium nikuda carbon bengabaveleli "-", ukuba baye inxalenye efanelekileyo dipole lwamanzi - hydrogen: CH ₃ Na + H ₂ Owu → CH ₄ + NaOH. Imveliso indlela abasabela ngayo, endaweni electrophilic - methane. Xa reactions heterolytic usebenzisana oppositely ebizwayo namaziko iimolekyuli, obanika noFaro ion e ezingaphiliyo izinto chemistry. It asimele sikubethe ngoyaba ukuba ukuguqulwa oganikhi khompawundi lunqabe sikhatshwe ukusekwa kwezi ukuse- kunye anions.

Unimolecular and abasabela bimolecular

Ukufaka nucleophilic yi monomolecular (SN1). Ngale ndlela, yimveliso ebaluleke yhuu haydrolisis organic kuyondelelaniswe - emfundo ephakamileyo butyl chloride. Inqanaba lokuqala kade, inxulunyaniswa dissociation ngcembe zibe carbonium zesiqinisekiso kunye anion chloride. Inqanaba lesibini yokusabela ngokukhawuleza kwenzeka kwaku- carbonium kunye namanzi. Inxaki ye abasabela ngayo ukufaka halogen kwi alkane ukuze afumane utywala hydroxy kwaye zamabanga aphantsi: (CH _{3) 3} C-Cl → (CH _{3) 3} C ^{+ +} Cl ^-; (CH _{3) 3} C ^{+ +} H ₂ O → (CH _{3) 3} C-OH ⁺ H +. Kuba-inyathelo elinye haydrolisis of halides alkyl eziziiprayimari neziziisekondari luphawulwa intshabalalo ngaxeshanye carbon ngenxa halogen kwaye ukuyilwa isibini C-OH. Le ndlela nucleophilic bimolecular endaweni (SN2).

indlela Heterolytic wokumelana

indlela endaweni kubandakanya transfer electron, ukudalwa nezakhiwo aphakathi. Indlela abasabela aqhubeke ngokukhawuleza ngakumbi, kungenza kube lula kakhulu ukuba intermediates eqhelekileyo kuye. Amaxesha amaninzi le nkqubo eya kumacala eziliqela ngaxeshanye. Uncedo uqhele ukufika indlela apho amasuntswana asetyenziswa, efuna inkcitho mncinane yamandla yokwakhiwa kwayo. Umzekelo, ubukho ibhondi kabini kwenyusa amathuba an zesiqinisekiso allyl CH 2 = CH-CH ₂ ^+, xa kuthelekiswa _CH3 ⁺ ion. Isizathu siyifumana electron lexinene iqhina ezininzi, ethi ichaphazele delocalization yoyalo ezintle, saa kulo lonke molecule.

benzene endaweni asabela

Iqela of iikhompawundi organic, obubonakala ngokuba yincwadi evuliweyo endaweni electrophilic - enkundleni. ring benzene - yinto elula ukuba ukuhlasela electrophilic. Le nkqubo iqala wayenelizwi reagent nokwehlukana yesibini, ngaloo ndlela yakheka electron ilifu electrophile ezikufutshane khonkcweni benzene. Isiphumo inguqu entsonkothileyo. unxibelelwano exabisekileyo amasuntswana electrophilic nomnye athom carbon kodwa, oko ababetsaleleke intlawulo yonke ezimbi "enuka ezintandathu" electron. Xa inyathelo lesithathu inkqubo electrophile omnye ring carbon atom ubopha isibini eziqhelekileyo elektroni (covalent bond). Kodwa kulo mzekelo, kukuba ukutshatyalaliswa 'enuka ezintandathu ", nto leyo disadvantageous ngokubhekiselele ekuphumezeni ozinzileyo karhulumente amandla izinzile. Kukho into enokuthi kubizwa ngokuba 'kukhululwe Proton. " Oku kwahluka ngaphandle H ^+, Nokubuyiselwa inkqubo yonxibelelwano oluzinzileyo, arenes ekuso. into Side iquka hydrogen Ukuqwalaselwa ikhonkco benzene kunye anion ukusuka reagent yesibini.

Imizekelo ngayo ukufaka organic chemistry

Kuba alkanes ingakumbi eqhelekileyo endaweni reaction. Imizekelo reactions electrophilic kwaye nucleophilic kungakhokelela cycloalkanes kunye arenes. ukusabela okufanayo kwi molekyuli kwezinto eziphilayo baphantsi kweemeko eziqhelekileyo, kodwa ngokuqhelekileyo - yaye zokufudumeza phambi ehlanganisa. Xa iinkqubo eziqhelekileyo yaye bafunda kakuhle ziquka endaweni electrophilic enuka kamnandi. Indlela abasabela ibalulekileyo yale hlobo:

1. Nitration of benzene ne-nitric acid phambi H ₂ SO ₄ - lulandela inkqubo: C ₆ H ₆ → C ₆ H _{5 Uyilo} okanye ucebo _2.
2. Le halogenation ekujonganeni of benzene, ingakumbi chlorination, ngenxa equation: C ₆ H ₆ + Cl ₂ → C ₆ H ₅ Cl + HCl.
3. sulfonation ibhedolaki of uqhubeka benzene with "lokhu" sulphuric acid, benzenesulfonic acid kwakheka.
4. Alkylation - indawo ye atom hydrogen ukusuka isangqa benzene ukuba alkyl.
5. Acylation - ukuyilwa ketones.
6. Formylation - ukususa hydrogen kwi iqela Cho ukuyilwa aldehydes.

Xa kufakwe reactions ziquka ukusabela alkanes kunye cycloalkanes, apho halogens ukuhlasela ekhoyo C-H bond. Derivatization esinxulunyaniswa kunye nokutshintshwa enye, ezimbini okanye zonke ezi athom hydrogen hydrocarbon isinyibiliko cycloparaffins. Uninzi galogenoalkanov sobunzima lwalusanda esezantsi asetyenziswa xa kusenziwa izinto ezininzi ezinzima ngoweqela kwiiklasi ezahlukeneyo. Iimpumelelo ezifunyenweyo ekufundeni ezisebenza reactions endaweni, wanikela negalelo enamandla kuphuhliso syntheses ngokusekelwe alkanes, cyclo-isigaba kunye hydrocarbon halogenated.