Likarabelo tse Ikhethang tsa Lihlopha tse Sebetsang
Likarabelo tsa lik'hemik'hale ke tsa bohlokoa k'hemistri, 'me lihlopha tse sebetsang ke likarolo tsa limolek'hule tse bohareng ba ts'ebetso ea lik'hemik'hale. Sehlopha se seng le se seng se sebetsang se na le karabelo le litšobotsi tsa sona, tse nolofalletsang mefuta e fapaneng ea liphetoho tsa lik'hemik'hale. Ho utloisisa likarabelo tse itseng tsa lihlopha tse sebetsang ke senotlolo sa ho laola le ho rala limolek'hule masimong a mangata, ho tloha meriana ho ea theknoloji ea thepa.
Lihlopha tse Sebetsang: Tlhaloso le Bohlokoa
Sehlopha se sebetsang ke sehlopha sa liathomo ka har'a molek'hule e sebetsang e le yuniti e arabelang 'me e fumana litšobotsi tsa lik'hemik'hale tsa molek'hule. Mehlala e tloaelehileng ea lihlopha tse sebetsang e kenyelletsa hydroxyl (-OH), carbonyl (C=O), carboxyl (-COOH), amino (-NH2), le ether (-COC). Sehlopha se seng le se seng se sebetsang se na le litšobotsi tse itseng tse arabelang tse lumellang liketso tse itseng tsa lik'hemik'hale ho etsahala.
Likarabelo tse Ikhethang tsa Lihlopha tse Sebetsang
1. Sehlopha sa Hydroxyl (-OH)
Lihlopha tsa Hydroxyl li teng ka har'a alcohols le phenols, 'me li bontša mefuta e fapaneng ea lik'hemik'hale tse itseng.
Karabelo ea ho ntša oksijene
Li-alcohol li ka oxidized ho hlahisa li-aldehydes, li-ketone, le li-carboxylic acid. Ho oxidized ha alcohol ho hlahisa li-aldehydes, tseo ka mor'a moo li oxidized ho ba li-carboxylic acid. Li-alcohol tsa bobeli li oxidized ho ba li-ketone.
``
R-CH2OH + [O] → R-CHO + [O] → R-COOH
R-CHOH-R' + [O] → R-CO-R'
``
Karabelo ea ho Fokotsa Metsi
Ho felloa ke metsi ha lialkhohole ho ka hlahisa li-alkene le li-ether. Ha ho na le asiti e matla joalo ka H2SO4, lialkhohole li felloa ke metsi ka har'a limolek'hule ho ea ho li-alkene kapa ho felloa ke metsi ka har'a limolek'hule ho ea ho li-ether.
``
R-CH2-CH2OH → R-CH=CH2 + H2O (ho omella ha metsi ka hare ho limolek'hule)
2 R-OH → ROR + H2O (ho felloa ke metsi ha limolek'hule)
``
2. Sehlopha sa Carbonyl (C=O)
Lihlopha tsa Carbonyl li fumanoa ka har'a aldehydes, ketones, le metsoako ea carboxylic. Likarabelo tsa tsona li kenyelletsa ho eketsa, ho fokotsa le ho kolobisa ha nucleophilic.
Ho Eketsa Nucleophilic
Khabone sehlopheng sa carbonyl e na le electrophilic 'me e ka hlaseloa ke nucleophile ho hlahisa joala.
``
R-CO-R' + NuH → RC(OH)(Nu)-R'
``
Karabelo ea Phokotso
Li-aldehyde le li-ketone li ka fokotsoa ho ba lino tse tahang ka ho fokotsa lintho tse kang NaBH4 kapa LiAlH4.
``
R-CHO + 2[H] → R-CH2OH
R-CO-R' + 2[H] → R-CHOH-R'
``
Karabelo ea Aldol Condension
Ho kolobisoa ha Aldol ho kenyelletsa limolek'hule tse peli tsa aldehyde kapa ketone tse hlahisang β-hydroxy aldehyde kapa ketone 'me li ka felloa ke metsi ho hlahisa enone.
``
2 R-CHO → R-CH(OH)-CH(R)-CHO
R-CHOH-CH(R)-CHO → R-CH=CH(R)-CHO + H2O
``
3. Sehlopha sa Carboxyl (-COOH)
Li-acid tsa carboxylic li bontša liketso tse kang ho tlosoa ha protonation, esterification le phokotso.
Karabelo ea ho se sebetse hantle
Li-acid tsa carboxylic (R-COOH) li ka lahleheloa ke liprothone ho etsa li-carboxylate (R-COO⁻).
``
R-COOH → R-COO⁻ + H⁺
``
Karabelo ea Esterification
Li-acid tsa carboxylic li arabela le li-alcohol ho hlahisa li-ester le metsi karabelong ea Fischer esterification.
``
R-COOH + R'OH → R-COO-R' + H2O
``
Karabelo ea Phokotso
Li-acid tsa carboxylic li ka fokotsoa ho ba li-alcohol ka ho sebelisa lintho tse fokotsang tse matla tse kang LiAlH4.
``
R-COOH + 4[H] → R-CH2OH + H2O
``
4. Sehlopha sa Amino (-NH2)
Lihlopha tsa li-amino li teng ka har'a li-amine 'me li bontša liketso tsa alkylation, acylation, le nitrosation.
Likarabelo tsa Alkylation le Acylation
Li-amine li thehoa ke alkylation ea li-alkyl halides le ammonia kapa li-amine. Li-amine li ka boela tsa arabela le li-acyl halides kapa li-anhydride ho hlahisa li-amides.
``
RX + NH3 → R-NH2 + HX
R-NH2 + R'-COCl → R-NH-CO-R' + HCl
``
Karabelo ea Nitrosation
Li-amine tsa mantlha le tsa bobeli li ka etsa liketso tsa nitrosation le nitrous acid ho hlahisa letsoai la diazonium bakeng sa li-amine tsa mantlha kapa li-amine tsa N-nitrose bakeng sa li-amine tsa bobeli.
``
R-NH2 + HONO → R-N2⁺ + H2O (letsoai la diazonium)
R2NH + HONO → R2N-N=O + H2O (N-nitroso amine)
``
5. Sehlopha sa Ether (COC)
Li-ether li arabela ka tsela e fapaneng le ea joala hobane ha li na liprothone tse ka lokolloang habonolo.
Karabelo ea ho Hlakola ha Acid
Li-ether li ka khaoloa ka li-acid tse matla ho hlahisa alcohols le alkyl halides.
``
RO-R' + HBr → R-OH + R'-Br
``
Karabelo ea Air Autooxide
Li-ether li ka oxidized ke moea ho hlahisa li-peroxide tsa ether tse phatlohang.
``
2 RO-R' + O2 → 2 RO-R'-O-OH
``
Qetello
Kutloisiso e batsi ea likarabelo tse itseng tsa lihlopha tse sebetsang k'hemistring ea lintho tse phelang ke ea bohlokoa bakeng sa mefuta e mengata ea lits'ebetso tse sebetsang. Lihlopha tse sebetsang li fumana litšobotsi tsa lik'hemik'hale le karabelo ea limolek'hule, e leng se nolofalletsang liphetoho tse fapaneng tsa bohlokoa tsa lik'hemik'hale k'hemistring ea lintho tse phelang tse entsoeng ka tlhaho, tsa baeloji le tsa thepa. Ka ho sebelisa tsebo ena, litsebi tsa lik'hemistri li ka rala le ho haha limolek'hule tse ncha ka lits'ebetso tse pharaletseng tlhokomelong ea bophelo bo botle, theknoloji le tse ling.
