Tali Fa'apitoa o Vaega Fa'atino
O tali atu fa'akemikolo o le fatu lea o le kemisi, ma o vaega fa'atino o vaega ia o molela'au o lo'o i le totonugalemu o gaioiga fa'akemikolo. O vaega fa'atino ta'itasi e iai lona lava tali atu ma uiga, e mafai ai ona faia ni suiga fa'akemikolo eseese. O le malamalama i tali atu fa'apitoa o vaega fa'atino o le ki lea i le fa'atonutonuina ma le mamanuina o molela'au i le tele o vaega, mai vaila'au i tekinolosi o meafaitino.
Vaega Fa'atino: Fa'amatalaga ma le Taua
O se vaega galue o se vaega o atomu i totonu o se mole e galue o se iunite tali atu ma fuafua ai meatotino fa'akemikolo o le mole. O fa'ata'ita'iga masani o vaega galue e aofia ai le hydroxyl (-OH), carbonyl (C=O), carboxyl (-COOH), amino (-NH2), ma le ether (-COC). O vaega galue ta'itasi e iai ona meatotino tali atu fa'apitoa e mafai ai ona tutupu ni tali fa'akemikolo fa'apitoa.
Tali Fa'apitoa o Vaega Fa'atino
1. Vaega hydroxyl (-OH)
O lo'o iai vaega hydroxyl i totonu o ava malosi ma phenols, ma e tele fo'i ni fa'atinoga fa'akemikolo fa'apitoa e latou te faia.
Tali atu o le Oxidation
E mafai ona fa'a'okeseneina ava malosi e maua ai aldehydes, ketones, ma carboxylic acids. O le fa'a'okeseneina muamua o ava malosi e maua ai aldehydes, ona fa'a'okeseneina lea i carboxylic acids. O ava malosi lona lua e fa'a'okeseneina i ketones.
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R-CH2OH + [O] → R-CHO + [O] → R-COOH
R-CHOH-R' + [O] → R-CO-R'
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Tali atu i le Fa'amago
O le fa'amago o ava malosi e mafai ona maua ai alkenes ma ethers. I le i ai o se acid malosi e pei o le H2SO4, e fa'amago ai ava malosi i totonu o le molecular i alkenes po'o le fa'amago i totonu o le molecular i ethers.
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R-CH2-CH2OH → R-CH=CH2 + H2O (fa'ama'i le tino i totonu o le molekula)
2 R-OH → ROR + H2O (fa'ama'i le vai i le va o molekula)
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2. Vaega Carbonyl (C=O)
E maua vaega o le carbonyl i totonu o aldehydes, ketones, ma carboxylic compounds. O a latou tali e aofia ai le nucleophilic addition, reduction, ma le condensation.
Fa'aopoopoga Nucleophilic
O le kaponi i le vaega carbonyl e electrophilic ma e mafai ona osofaʻia e se nucleophile e maua ai se ava malosi.
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R-CO-R' + NuH → RC(OH)(Nu)-R'
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Tali Fa'aitiitia
E mafai ona fa'aitiitia aldehydes ma ketones i ni ava malosi e ala i mea fa'aitiitia e pei o le NaBH4 po'o le LiAlH4.
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R-CHO + 2[H] → R-CH2OH
R-CO-R' + 2[H] → R-CHOH-R'
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Tali atu o le Fa'aputuga o le Aldol
O le fa'aputuga o le aldol e aofia ai ni molela'au aldehyde se lua po'o ni molela'au ketone e gaosia ai se β-hydroxy aldehyde po'o se ketone ma e mafai ona fa'amamago ma maua ai se enone.
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2 R-CHO → R-CH(OH)-CH(R)-CHO
R-CHOH-CH(R)-CHO → R-CH=CH(R)-CHO + H2O
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3. Vaega Carboxyl (-COOH)
E fa'aalia e carboxylic acid ni tali e pei o le deprotonation, esterification, ma le reduction.
Tali atu o le Deprotonation
E mafai e le carboxylic acids (R-COOH) ona fa'aitiitia protons e fausia ai carboxylates (R-COO⁻).
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R-COOH → R-COO⁻ + H⁺
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Tali atu i le Esterification
E tali atu acids carboxylic ma alcohols e maua ai esters ma le vai i le tali atu o le Fischer esterification.
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R-COOH + R'OH → R-COO-R' + H2O
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Tali Fa'aitiitia
E mafai ona fa'aitiitia acids carboxylic i ni ava malosi e fa'aaoga ai ni mea fa'aitiitia malolosi e pei o le LiAlH4.
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R-COOH + 4[H] → R-CH2OH + H2O
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4. Vaega Amino (-NH2)
O vaega amino o loʻo iai i amines ma faʻaalia ai tali o le alkylation, acylation, ma le nitrosation.
Tali atu i le Alkylation ma le Acylation
E fausia amines e ala i le alkylation o alkyl halides ma le ammonia po'o amines. E mafai fo'i e Amines ona tali atu ma acyl halides po'o anhydrides e maua ai amides.
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RX + NH3 → R-NH2 + HX
R-NH2 + R'-COCl → R-NH-CO-R' + HCl
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Tali atu i le Nitrosation
E mafai e amine muamua ma amine lona lua ona faia ni tali o le nitrosation ma le nitrous acid e maua ai le diazonium salts mo amine muamua po'o N-nitrose amines mo amine lona lua.
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R-NH2 + HONO → R-N2⁺ + H2O (masima diazonium)
R2NH + HONO → R2N-N=O + H2O (N-nitroso amine)
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5. Vaega Eteru (COC)
E ese le tali atu o ethers nai lo ava malosi ona e leai ni protons e faigofie ona fa'asa'olotoina.
Tali atu o le Vaevae o le 'Aseta
E mafai ona vaevaeina ethers e ala i acids malolosi e maua ai alcohols ma alkyl halides.
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RO-R' + HBr → R-OH + R'-Br
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Tali atu o le Ea Autooxide
E mafai ona fa'a'okeseneina ethers i le ea e maua ai ni ether peroxides pāpā.
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2 RO-R' + O2 → 2 RO-R'-O-OH
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I'uga
O se malamalamaga mae'ae'a i tali fa'apitoa o vaega fa'atino i le kemisi fa'aola e taua tele mo le tele o fa'aoga fa'atino. O vaega fa'atino e fuafua ai meatotino fa'akemikolo ma le tali atu o molela'au, ma mafai ai ona faia le tele o suiga taua o kemikolo i le kemisi fa'aola, fa'aolaola, ma meafaitino. I le fa'aaogaina o lenei malamalama, e mafai ai e le au kemisi ona mamanuina ma fausia ni molela'au fou ma fa'aoga lautele i le tausiga o le soifua maloloina, tekinolosi, ma isi mea.
