Shaanxi BLOOM Tech Co., Ltd. yog ib tug ntawm cov uas paub txog manufacturers thiab lwm tus neeg ntawm acetaldehyde kua cas 75-07-0 nyob rau hauv Suav teb. Txais tos rau cov lag luam wholesale bulk zoo acetaldehyde kua cas 75-07-0 muag ntawm no los ntawm peb lub hoobkas. Kev pabcuam zoo thiab tus nqi tsim nyog muaj.
Cov tshuaj Acetaldehyde, tseem hu ua acetaldehyde, yog ib qho organic compound, CAS 75-07-0, Cov tshuaj formula yog CH3CHO. Raws li aldehyde ketone cov organic tebchaw, nws yog cov kua tsis muaj xim thiab pob tshab nrog cov ntxhiab tsw ntxhiab, tsis muaj zog thiab flammable. Nws yog ib qho yooj yim soluble hauv dej thiab tuaj yeem sib xyaw rau hauv ib qho kev faib ua feem nrog cov kuab tshuaj organic xws li ethanol, ether, benzene, roj av, toluene, thiab lwm yam. Nws yog siv los ua tus neeg sawv cev txo qis, fungicide thiab cov txheej txheem kev daws teeb meem rau kev txiav txim siab colorimetric ntawm aldehydes. Siv hauv kev lag luam rau kev tsim acetaldehyde, acetic acid, hluavtaws roj hmab, thiab lwm yam.
Dav siv los ua raw khoom, tshuaj tua kab mob, tawg, txo cov neeg ua haujlwm rau cov organic synthesis ntawm acetic acid, acetic anhydride, butanol, polyacetaldehyde, hluavtaws roj hmab thiab lwm yam khoom, thiab tseem siv tau los npaj cov txheej txheem kev daws teeb meem rau formaldehyde kev txiav txim los ntawm txoj kev colorimetric. Kev tsim khoom ntawm acetaldehyde suav nrog txoj hauv kev xws li ncaj qha oxidation ntawm ethylene, oxidation ntawm ethanol, ncaj qha hydration ntawm acetylene, dehydrogenation ntawm ethanol, thiab hydrogenation ntawm acetic acid. Nws cov khoom lag luam qis suav nrog pyridine, crotonaldehyde, thiab sorbic acid.
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Tshuaj Formula |
C2H4O |
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Exact Mass |
44 |
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Molecular Luj |
44 |
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m/z |
44 (100.0%), 45 (2.2%) |
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Elemental Analysis |
C, 54.53; H, 9.15; O, 36.32 |
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1. Catalytic oxidation ntawm acetaldehyde
2. Acetaldehyde combustion
3. Cov iav iav tiv thaiv
4. Acetaldehyde thiab npaj tshiab tooj liab hydroxide
5. Acetaldehyde reacts nrog hydrogen los tsim ethanol
Cov tshuaj Acetaldehydetuaj yeem ua rau ntau txoj hauv kev:
1. Ethylene ncaj qha oxidation txoj kev ethylene thiab oxygen yog ncaj qha oxidized rau synthesize crude acetaldehyde nyob rau hauv ib kauj ruam los ntawm ib tug catalyst uas muaj palladium chloride, tooj liab chloride, hydrochloric acid thiab dej, thiab ces cov khoom tiav yog tau los ntawm distillation.
2. Ethanol oxidation txoj kev acetaldehyde tau npaj los ntawm huab cua oxidative dehydrogenation ntawm ethanol vapor ntawm 300-480℃siv nyiaj, tooj liab lossis nyiaj tooj liab alloy mesh los yog cov khoom ua catalyst.
3. Acetylene ncaj qha hydration txoj kev acetylene thiab dej yog ncaj qha hydrated nyob rau hauv qhov kev txiav txim ntawm mercury catalyst los yog tsis mercury catalyst kom tau acetaldehyde. Vim qhov teeb meem ntawm mercury puas tsuaj, nws tau maj mam hloov los ntawm lwm txoj kev.
4. Ethanol dehydrogenation txoj kev nyob rau hauv lub xub ntiag ntawm tooj liab catalyst nrog cobalt, chromium, zinc los yog lwm yam tebchaw, ethanol yog dehydrogenated los tsim acetaldehyde.
5. Saturated hydrocarbon oxidation txoj kev. Kev siv cov khoom siv raw: 610kg ntawm 99% acetylene ib tuj ntawm cov khoom tsim los ntawm acetylene hydration; ethanol oxidation txoj kev noj 1200kg ntawm 95% ethanol; Txoj kev ethylene oxidation (ib-txoj kev) siv 710kg ntawm 99% ethylene thiab 300m3 ntawm oxygen (99%). Kev lag luam kev lag luam acetaldehyde, purity ntawm acetaldehyde los ntawm ethylene txoj kev yog 99.7%, thiab purity ntawm acetaldehyde los ntawm ethanol txoj kev yog 98%.
Cov tshuaj Acetaldehydeyog ib qho xim tsis muaj xim, pob tshab, thiab cov kua dej tsis haum nrog cov ntxhiab tsw. Cov pab pawg aldehyde (- CHO) nyob rau hauv nws cov qauv molecular endows nws muaj siab reactivity thiab tuaj yeem koom nrog ntau yam tshuaj lom neeg. Nws yog dav siv hauv tshuaj, tshuaj, zaub mov, tshuaj txhua hnub, kev ua liaj ua teb thiab lwm yam.
Cov cheeb tsam tseem ceeb: Tshuaj intermediates thiab cov kuab tshuaj
Acetic acid thiab acetate ntau lawm
Nws yog cov khoom siv tseem ceeb rau acetic acid (CH3 COOH), uas hloov acetaldehyde rau hauv acetic acid los ntawm oxidation cov tshuaj tiv thaiv (xws li txoj kev Wacker), thiab ntxiv synthesizes derivatives xws li vinyl acetate thiab acetic anhydride. Acetic acid yog siv los ua cov tshuaj acidic hauv textile printing thiab dyeing los txhim kho cov nyhuv dyeing ntawm fabrics; Raws li kev tswj hwm acidity hauv kev lag luam khoom noj, nws tau siv dav hauv kev tsim cov seasonings thiab cov kaus poom zaub mov. Vinyl acetate yog cov khoom siv tseem ceeb rau kev tsim cov cellulose acetate (xws li zaj duab xis substrates thiab plastics), thiab acetaldehyde plays lub luag haujlwm tseem ceeb hauv cov txheej txheem no.
Synthesis ntawm Pentaerythritol
Acetaldehyde condenses nrog peb lub molecules ntawm formaldehyde nyob rau hauv alkaline tej yam kev mob los tsim pentaerythritol (C (CH ₂ OH) ₄), ib qho tseem ceeb polyol siv nyob rau hauv kev tsim cov resins, coatings, lubricants, thiab explosives (xws li pentaerythritol tetranitrate). Cov derivatives ntawm pentaerythritol yog irreplaceable nyob rau hauv teb xws li aerospace thiab electronic ntim. Acetaldehyde, raws li qhov pib taw tes ntawm cov tshuaj tiv thaiv, ncaj qha txiav txim siab ntawm kev lag luam saw txuas ntxiv.
Kev npaj ntawm Pyridine thiab nws cov Derivatives
Nws reacts nrog ammonia nyob rau hauv qhov kev txiav txim ntawm ib tug catalyst los tsim pyridine, uas yuav siv tau ntxiv mus synthesize vitamin B3 (niacin), anti tuberculosis tshuaj isoniazid, thiab lwm yam. Pyridine tebchaw tuav ib tug tseem ceeb txoj hauj lwm nyob rau hauv cov tshuaj, tshuaj tua kab, thiab dyeing industries. Piv txwv li, pyridine reacts nrog chloroacetic acid rau synthesize herbicide 2,4-D, thiab kev koom tes ntawm acetaldehyde ua rau cov synthesis ntawm cov khoom muaj nqis ntxiv tau.
Solvent thiab tu tus neeg sawv cev
Nws tuaj yeem yaj cov resins, roj, thiab ntau yam khoom siv organic, thiab feem ntau yog siv rau kev ntxuav hlau, hluav taws xob tiv thaiv degreasing, thiab precision ntsuas decontamination. Hauv kev tsim khoom semiconductor, acetaldehyde yog siv los ntxuav cov residual photoresist ntawm qhov chaw ntawm silicon wafers. Nws cov yam ntxwv tsis tshua muaj zog tuaj yeem nkag mus rau micrometer qib qhov khoob, ua kom huv si raws li nanometer qib qauv. Txawm hais tias qee daim ntawv thov tau raug hloov vim muaj teeb meem toxicity, nws tseem nyuaj rau hloov tag nrho rau hauv siab -txoj kev tu kom huv.
Lub Hom Phiaj Tshwj Xeeb: Kev lag luam kws tshuaj thiab zaub mov
Synthesis ntawm kws tshuaj intermediates
Cov tshuaj tua kab mob thiab tshuaj tua kab mob: Lawv koom nrog hauv kev sib txuas ntawm cov kab sib txuas ntawm cov tshuaj tua kab mob xws li penicillin thiab cephalosporins, thiab qhia cov pab pawg ua haujlwm tshwj xeeb los ntawm cov tshuaj tiv thaiv aldol condensation los txhim kho kev ua yeeb yam. Piv txwv li, tom qab condensation thiab hydrolysis nrog cyanide ions thiab ammonia, cov khoom siv tuaj yeem siv los tsim cov alanine, uas tuaj yeem siv ntxiv los ua kom cov tshuaj tiv thaiv kab mob gabapentin.
Kev tsim cov vitamins: Acetaldehyde yog ib qho tseem ceeb raw khoom rau synthesis ntawm vitamin B ₁ (thiamine), uas condenses nrog cyanoacetic acid los ua ib lub nplhaib thiazole thiab thaum kawg tsim vitamin B ₁ molecules. Tsis tas li ntawd, acetaldehyde kuj tseem siv los ua ib qho nruab nrab rau cov synthesis ntawm vitamin A, - ionone, thiab nws cov tshuaj tiv thaiv xaiv ncaj qha cuam tshuam rau cov txiaj ntsig ntawm vitamin A.
Tshuaj loog thiab tshuaj tsaug zog: Lawv yog chlorinated los tsim trichloroacetaldehyde, thiab lawv cov hydrate (chloral hydrate) tau dav siv los ua sedative hypnotic tshuaj. Txawm hais tias nws tau raug hloov los ntawm lwm txoj kev nyab xeeb vim muaj kev phiv, nws tseem muaj cov ntawv thov hauv kev kho tsiaj.
Khoom noj khoom haus additives thiab essence
Tus neeg sawv cev seasoning: Cov kab ntawm cov tshuaj no ib txwm muaj nyob hauv kas fes, khob cij, thiab txiv hmab txiv ntoo siav, muab lawv ib qho tshwj xeeb aroma. Hauv kev lag luam, acetaldehyde yog siv los npaj cov txiv hmab txiv ntoo xws li txiv kab ntxwv, txiv kab ntxwv thiab txiv apples, thiab cov txiv hmab txiv ntoo xws li cawv txiv hmab thiab rum. Qhov concentration ntawm acetaldehyde nyob rau hauv cov khoom qab zib kawg yog li ntawm 3.9 ~ 270 mg / kg.
Preservatives: tuaj yeem inhibit microbial kev loj hlob thiab txuas ntxiv lub neej txee ntawm cov zaub mov. Piv txwv li, hauv cheese ntau lawm, acetaldehyde yog siv los tiv thaiv pwm kab mob thaum txhim kho cov tsw ntawm cheese.
Deinonylation txheej txheem: Nws yog ib zaug siv rau kas fes deintercalation los ntawm extracting caffeine thiab distilling kom rov qab cov kuab tshuaj. Txawm hais tias supercritical CO2 extraction technology tau maj mam nrov, nws cov txheej txheem tseem khaws cia hauv qee thaj tsam.
Ntxiv rau cov khoom siv tshuaj txhua hnub
Shampoo thiab da dej gel: Raws li lubricants, lawv tuaj yeem txhim kho kev ntxhib los mos ntawm cov khoom, ua rau cov plaub hau mos thiab tawv nqaij. Nws tsis tshua muaj volatility ua kom muaj kev ruaj ntseg thaum lub sij hawm cov khoom cia, thiab nws kuj koom nrog hauv kev tso tawm qeeb ntawm cov ntsiab lus kom ntev lub sijhawm khaws cov tshuaj tsw qab.
Tshuaj pleev ib ce: Acetaldehyde yog siv los tsim cov tshuaj antioxidants, tiv thaiv cov roj oxidation thiab rancidity hauv formulations, thiab txuas ntxiv cov khoom txee lub neej. Tsis tas li ntawd, nws cov derivatives (xws li glyoxylic acid) yog siv los ua cov khoom xyaw ua kom tawv nqaij, txo melanin ntau lawm los ntawm inhibiting tyrosinase kev ua.
(1) Sp2 hybridization
Cov qauv ntawm aldehydes thiab ketones ob leeg muaj cov pa roj carbon oxygen ob daim ntawv cog lus (- C=O, carbonyl). Cov pa roj carbon atom tsim peb sp2 hybridized orbitals nrog cov pa atom thiab ob lub atoms, ua peb sigma daim ntawv cog lus nyob rau hauv tib lub dav hlau nrog lub kaum sab xis ntawm kwv yees li 120 degree. Qhov seem p orbital ntawm carbonyl carbon uas tsis koom rau hauv hybridization overlaps nrog ib p orbital ntawm cov pa atom los ntawm sab los tsim ib tug π daim ntawv cog lus, thaum ob lub p orbitals ntawm cov pa atom muaj ob khub ntawm ib leeg electrons.
Noj formaldehyde, uas muaj cov qauv yooj yim tshaj plaws, piv txwv li, carbon oxygen ob daim ntawv cog lus thiab carbon hydrogen ib daim ntawv cog lus ntev yog 120.3 teev tsaus ntuj thiab 110 teev tsaus ntuj, feem.
Vim tias qhov ntau dua electronegativity ntawm oxygen atoms piv rau carbon atoms, cov huab cua electron nyob rau hauv cov pa roj carbon ob daim ntawv cog lus yuav ua rau biased ntawm oxygen atoms, uas ua rau ib tug ntau dua electron huab ceev nyob ib ncig ntawm lawv, thaum lub electron huab ceev ntawm carbon atoms yog qis dua. Yog li ntawd, carbonyl pawg muaj polarity, thiabCov tshuaj Acetaldehydeyog ib tug polar molecule, uas kuj piav qhia vim li cas acetaldehyde yog yooj yim soluble nyob rau hauv polar solvents (zoo solubility).
(2) Alpha hydrogen atom
① Tsis muaj zog acidic
Cov alpha hydrogen atoms ntawm aldehydes thiab ketones muaj zog heev rau ob lub ntsiab yog vim li cas: ua ntej, lub electron tshem tawm induction nyhuv ntawm carbonyl pawg; Qhov thib ob yog cov nyhuv hyperconjugation ntawm alpha carbon hydrogen bonds ntawm carbonyl pawg.
Noj 2-methylcyclohexanone ua piv txwv, isotope pauv kev sim tau pom tias alpha hydrogen atom ntawm ib sab ntawm pawg carbonyl muaj kev ua haujlwm siab thiab tuaj yeem hloov tau los ntawm deuterium atoms nyob rau hauv qhov kev txiav txim ntawm deuterated sodium oxide (hnyav sodium hydroxide, NaOD) thiab dej hnyav (D2O).
Txawm hais tias alpha H kev ua ntawm cov sib txawv carbonyl sib txawv, aldehydes muaj zog acidity piv rau alkanes, alkynes, thiab ketones ntawm tib lub koob. Ntawm qhov tod tes, qhov steric hindrance ntawm alkyl pawg yog ntau dua li ntawm hydrogen atoms, thiab ntawm qhov tod tes, cov nyhuv hyperconjugation ntawm alkyl pawg thiab carbonyl pawg txo cov nqi zoo ntawm carbonyl carbons.
Nco tseg: p sawv cev rau qhov tsis zoo logarithm, thiab qhov me dua pKa, qhov muaj zog acidity.
② Tautomerism
Feem ntau, feem ntau aldehydes thiab ketones muaj tautomers. Noj acetaldehyde ua piv txwv, muaj tautomers ntawm ketone thiab enol cov ntaub ntawv. Vim qhov tsis ruaj khov ntawm cov qauv enol, ketone daim ntawv qauv ntawm acetaldehyde suav txog yuav luag 100%, nrog rau qhov sib npaug ntawm li 6.0 × 10-5.
Lus Cim: Yog vim li cas rau qhov tsis ruaj khov ntawm cov qauv enol yog tias muaj cov pa roj carbon ob daim ntawv cog lus ua rau kom qhov ceev ntawm π electron huab ntawm cov pa roj carbon atom. Txawm li cas los xij, vim muaj zog electronegativity ntawm oxygen, cov huab cua electron zoo li mus ze rau cov pa atom. Qhov kev tsis sib haum xeeb no ua rau muaj kev tsis sib haum xeeb ntawm cov qauv enol.
③ Aldol condensation
Nyob rau hauv qhov kev txiav txim ntawm dilute alkaline tov, acetaldehyde molecules tuaj yeem raug aldol condensation cov tshuaj tiv thaiv ntawm qhov kub thiab txias, qhov twg - hydrogen atoms tawm tsam carbonyl oxygen atoms, thiab lwm pab pawg ua haujlwm ua ke nrog carbonyl carbon atoms los ua - hydroxybutyraldehyde, uas ua rau ob npaug ntawm cov pa roj carbon atoms.
(3) Nucleophilic ntxiv
Tus nqi zoo ntawm cov pa roj carbon atom hauv cov qauv carbonyl tau yooj yim tawm tsam los ntawm nucleophiles, thiab tuaj yeem raug π - daim ntawv cog lus cleavage ntxiv cov tshuaj tiv thaiv nyob rau hauv acidic thiab alkaline ib puag ncig.
① Hydrocyanic acid
Hydrocyanic acid yog ib qho nucleophile ib txwm ua nrogCov tshuaj Acetaldehydelos tsim 2-hydroxypropionitrile (- hydroxynitrile). Cov tshuaj tiv thaiv tus nqi yuav nrawm heev nyob rau hauv alkaline tej yam kev mob vim hais tias HCN, raws li ib tug qaug zog acid, nws yog ib qho yooj yim mus tsim cyanide tsis zoo ions (CN -) nyob rau hauv alkaline tej yam kev mob, li no nce lub concentration ntawm reactants; Ntawm qhov tsis sib xws, yog tias ua tau raws li cov kua qaub, hydrogen ions tau txais protonation nrog carbonyl pawg, txhim kho cov electrophilicity ntawm carbonyl carbons, uas tsis tsim nyog rau kev nce qib ntawm cov tshuaj tiv thaiv thiab qeeb cov tshuaj tiv thaiv.
HCN + NaOH → NaCN + H2O
CH3CHO + HCN → CH3-CH(OH)-CN
Tsis tas li ntawd, 2-hydroxypropionitrile tuaj yeem hydrolyzed nyob rau hauv acidic tej yam kev mob los tsim 2-hydroxypropionic acid (feem ntau hu ua "lactic acid"). Yog li ntawd, cov nucleophilic ntxiv cov tshuaj tiv thaiv ntawm hydrogen cyanide tuaj yeem siv los ua ke hydroxy acids nrog rau cov pa roj carbon ntxiv.
CH3-CH(OH)-CN + 2H2O + H+ → CH3-CH(OH)-COOH + NH4+
② Sodium bisulfite
Acetaldehyde thiab ntau saturated sodium bisulfite tov tuaj yeem dhau los ua cov tshuaj tiv thaiv nucleophilic los tsim sodium bisulfite adducts yam tsis tas yuav muaj lub catalyst.
CH3CHO + NaHSO3 → CH3-CH(OH)-SO3Na
Cov sodium bisulfite adduct (sodium alpha hydroxysulfonate) yooj yim soluble hauv dej tab sis nyuaj rau yaj hauv cov kuab tshuaj organic, yog li nws diffuses los ntawm cov organic theem mus rau theem aqueous los tsim cov muaju. Yog li, cov tshuaj tiv thaiv no tuaj yeem siv los cais cov aldehydes los ntawm cov organic tebchaw uas tsis muaj dej nyob hauv dej.
Lus Cim: Sodium alpha hydroxysulfonate reacts nrog sodium cyanide, thiab sulfonic acid pawg tuaj yeem hloov tau los ntawm pawg cyanide los tsim alpha hydroxynitrile (nitrile cawv), yog li zam kev tsim cov tshuaj lom thiab tsis haum tshuaj hydrogen cyanide.
CH3-CH(OH)-SO3Na + NaCN → CH3-CH(OH)-CN + Na2SO3
③ Hom reagent
Acetaldehyde tuaj yeem hnov mob nrog Grignard reagent (feem ntau hu ua "Grignard reagent", abbreviated li "RMgX") nyob rau hauv lub xub ntiag ntawm anhydrous ether, thawj tsim magnesium hloov cov tebchaw (cov khoom nruab nrab), thiab tom qab ntawd hydrolyzing nyob rau hauv acidic tej yam kev mob rau ncaj qha tsim cawv. Cov tshuaj tiv thaiv no kuj yog ib txoj hauv kev los tsim cov cawv los ntawm nucleophilic ntxiv cov tshuaj tiv thaiv, zoo ib yam li cov organic lithium reagents.
Noj cov tshuaj tiv thaiv ntawm cyclohexane ua hydrocarbon raws li reagent nrog acetaldehyde ua piv txwv.
CH3CHO + C6H11-MgX → H11C6-CH(OH)-CH3
Lus Cim: Hom reagent tau tsim los ntawm Fab Kis tus kws tshawb fawb Francois Auguste Victor Grignard (1871-1935) hauv xyoo 1901. Nws yog ib qho organic magnesium reagent tsim los ntawm reacting organic halogen (chlorine, bromine, iodine) cov tebchaw (halogenated alkanes, nquag halogenated aromatic hydrocarbons nyob rau hauv ib qho chaw qhuav).
④ Cawv
Cawv kuj muaj affinity, thiab nyob rau hauv catalysis ntawm acids xws li p-toluenesulfonic acid thiab hydrogen chloride, lawv muaj peev xwm undergo nucleophilic ntxiv cov tshuaj tiv thaiv nrog acetaldehyde los tsim tsis ruaj tsis khov hemiacetals, uas tom qab ntawd tshem tawm los ntawm ib tug molecule ntawm dej los tsim acetals.
Cov tshuaj tiv thaiv tshwj xeeb yog raws li hauv qab no: ua ntej, cov carbonyl thiab hydrogen ions raug protonation los ua oxonium ions, uas ua rau cov electrophilicity ntawm carbonyl carbon atom; Thib ob, thaum ntxiv cov tshuaj tiv thaiv nrog cawv, protons ploj, ua rau tsim cov hemiacetals tsis ruaj khov; Tom qab ntawd, nws txuas nrog H + los tsim oxonium ions rau lub cev qhuav dej; Thaum kawg, nws hnov mob nrog cawv los tsim ib qho chaw ruaj khov aldehyde, thiab tag nrho cov txiaj ntsig yog tias ib qho molecule ntawm aldehyde ketone tuaj yeem hnov mob nrog ob lub cawv ntawm cawv los ua ib qho molecule ntawm aldehyde.
Noj methanol ua piv txwv, nws tuaj yeem hnov mob nrog acetaldehyde los tsim dimethoxyethane (aldehyde).
CH3CHO + 2CH3OH → (H3CO)2-CH-CH3 + H2O
⑤ Dej
Hauv cov cheeb tsam acidic, dej tuaj yeem ua rau muaj kev cuam tshuam ntxiv nucleophilic nrog acetaldehyde los tsim dihydroxyethane (diol).
CH3CHO + H2O → (HO)2-CH-CH3
Lus Cim: Cov qauv molecular ntawm ob pawg hydroxyl txuas los ntawm tib cov pa roj carbon atom tsis muaj kev ruaj ntseg thermodynamic thiab zoo li rov qab mus rau aldehydes thiab ketones thaum lub cev qhuav dej, qhia tias cov tshuaj tiv thaiv ntxiv ntawm dej thiab carbonyl yog cov tshuaj tiv thaiv rov qab nrog kev sib npaug ntawm kev sib npaug ntawm sab reactant.
⑥ Ammonia thiab nws cov derivatives
Tag nrho cov aldehydes thiab ketones tuaj yeem ua rau muaj kev cuam tshuam nucleophilic ntxiv nrog ammonia thiab nws cov derivatives (xws li hydroxylamine, hydrazine, phenylhydrazine, semicarbazide, thiab lwm yam), ua cov khoom ruaj khov xws li oxime, hydrazone, phenylhydrazone, thiab urea. Txawm li cas los xij, cov khoom tau los ntawm cov tshuaj tiv thaiv nrog ammonia tsis ruaj khov.
Noj 2,4-dinitrophenylhydrazine ua piv txwv, cov tshuaj sib npaug rau cov tshuaj tiv thaiv nrog acetaldehyde thiab lub cev qhuav dej los tsim 2,4-dinitrophenylhydrazone yog qhia hauv daim duab.
Lus Cim: Oxime, hydrazone, thiab urea yog feem ntau ruaj khov crystals nrog ib qho chaw ruaj khov. Hydrolysis nyob rau hauv acidic ib puag ncig tuaj yeem kho cov qauv carbonyl. Yog li, cov tshuaj nucleophilic no tuaj yeem siv los txheeb xyuas thiab ntxuav aldehydes thiab ketones.
Cov khoom ntawm tej yam amine derivatives reacting nrog carbonyl pawg
(4) Cov tshuaj tiv thaiv oxidation
① Xim tshuaj tiv thaiv
aldehyde pawg ntawmCov tshuaj Acetaldehydemolecules tuaj yeem oxidized rau - COO - los ntawm Fehling reagent thiab Tollens reagent, ua cib liab precipitate (Cu2O) thiab nyiaj iav (elemental Ag), feem. Lub hauv paus ntsiab lus ntawm kev txheeb xyuas aldose (txo cov suab thaj) nyob rau hauv qhov no, thiab cov tshuaj tiv thaiv uas tshwm sim nrog Tollens reagent (yuav tsum tau cua sov) kuj hu ua "silver mirror reaction" [3].
CH3CHO + 2Ag(NH3)2OH → 2Ag↓+ 3NH3↑+ 2H2O + CH3COONH4
CH3CHO + 2Cu(OH)2 → Cu2O↓+ 2H2O + CH3COOH
Lus Cim: Fehling reagent thiab Tollens reagent yog ob qho tib si reagents uas tuaj yeem txheeb xyuas cov khoom txo qis. Cov qub feem ntau yog tsim los ntawm sodium hydroxide (NaOH) thiab tooj liab sulfate (CuSO4) tov, tsim los ntawm German chemist Herman von Fehling (1812-1885) hauv 1849; Cov tom kawg tuaj yeem npaj tau hauv qhov chaw, thiab nws cov ntsiab lus tseem ceeb yog cov tshuaj ammonia ntawm cov nyiaj nitrate, uas yog Ag (NH3) OH, tseem hu ua "silver ammonia solution", tsim los ntawm German chemist Bernhard Tollens (1841-1918) nyob rau hauv lub xyoo pua 19th.
② Muaj zog oxidizing tus neeg sawv cev
Vim qhov txo qis ntawm aldehyde pawg, lawv tuaj yeem oxidized rau acetic acid los ntawm inorganic muaj zog oxidant poov tshuaj permanganate. Nyob rau hauv acidic tej yam kev mob, poov tshuaj permanganate txo mus rau divalent manganese ions, uas ua rau fading ntawm lub sib sib zog nqus ntshav daws; Nyob rau hauv cov xwm txheej alkaline, nws raug txo kom IV valent manganese dioxide, thiab qhov tshwm sim yog tias cov kua dej sib sib zog nqus ploj mus, ua rau cov xim av xim av dub. Qhov sib npaug ion yog raws li nram no.
5CH3CHO + 2MnO4- + 6H+ →2Mn2+ + 5CH3COOH +3H2O
3CH3CHO + 2MnO4- + H2O →2MnO2↓+ 3CH3COOH + 2OH-
Nco tseg: Potassium permanganate muaj zog oxidizing zog nyob rau hauv acidic ib puag ncig thiab txo qis valence tebchaw. Cov oxidants muaj zog zoo xws li potassium dichromate (K2Cr2O7), chromic acid (H2CrO4), hydrogen peroxide (H2O2), thiab lwm yam.
③ Catalytic oxidation
Nyob rau hauv catalysis thiab cua kub tej yam kev mob ntawm tooj liab hlau, acetaldehyde yuav oxidized los ntawm oxygen mus rau acetic acid. Ua ntej, tooj liab reacts nrog oxygen nyob rau hauv cov cua kub tej yam kev mob los tsim tooj liab oxide, uas ces ua raws li ib tug oxidant thiab reacts nrog acetaldehyde kom txo tau nws tus kheej mus rau elemental tooj liab (catalyst) [2] [20-28].
2Cu + O2 → 2CuO
CH3CO + CuO → Cu + CH3COOH
2CH3CHO + O2 → 2CH3COOH
④ Oxygen (combustion)
Acetaldehyde, raws li cov organic compound, tuaj yeem hlawv hauv oxygen los tsim carbon dioxide thiab dej (ua tiav oxidized).
2CH3CHO + 5O2 → 4CO2 + 4H2O
(5) Txo cov tshuaj tiv thaiv
Acetaldehyde muaj unsaturated carbon oxygen ob daim ntawv cog lus (- C=O), uas tuaj yeem txo qis rau hydroxymethyl (- CH2OH) los ntawm kev txo cov neeg ua haujlwm.
① Catalytic hydrogenation
Acetaldehyde tuaj yeem txo qis rau ethanol los ntawm hydrogen gas nyob rau hauv qhov kev txiav txim ntawm cov hlau catalysts xws li npib tsib xee thiab palladium.
CH3CO + H2 → CH3CH2OH
② Hlau hydride
Acetaldehyde tuaj yeem txo qis rau ethanol los ntawm cov hlau hydrides (muaj zog txo cov neeg ua haujlwm) xws li lithium aluminium hydride, sodium borohydride, thiab lwm yam nyob rau hauv anhydrous ether mob.
CH3CHO + LiAlH4 +2H2O → CH3CH2OH + LiAlO2 + 3H2↑
CH3CHO + NaBH4 + 3H2O → CH3CH2OH + NaBO3 + 4H2↑
③ Clemmensen kho dua tshiab
Nyob rau hauv qhov kev txiav txim ntawm HCl thiab zinc mercury (Zn Hg), pawg aldehyde ntawm acetaldehyde tuaj yeem txo qis rau methyl, uas yog, acetaldehyde raug txo rau ethane nyob rau hauv muaj zog acidic tej yam kev mob. Cov tshuaj tiv thaiv no tsim nyog rau kev txo qis ntawm carbonyl tebchaw uas nkag siab rau alkali.
Hg tsis koom nrog Clemmensen txo cov tshuaj tiv thaiv, tab sis ua raws li cov khoom siv. Tom qab tsim cov mercury amalgam (Zn Hg) alloy nrog zinc, cov haujlwm ntawm zinc yog nce vim qhov tsim ntawm ob peb hluav taws xob hauv cov hlau, yog li txhawb cov tshuaj tiv thaiv.
Zinc amalgam tuaj yeem npaj los ntawm kev ua haujlwm zinc hmoov / zinc hais nrog mercury ntsev (HgCl2) hauv dilute hydrochloric acid tov. Elemental zinc tuaj yeem txo qhov sib txawv ntawm cov mercury ions mus rau lub ntsiab lus mercury, thiab tom qab ntawd mercury tsim cov mercury amalgam rau ntawm zinc, thiab cov tshuaj tiv thaiv txo tau tshwm sim ntawm qhov chaw ua haujlwm ntawm zinc.
Lus Cim: Clemmensen txo cov tshuaj tiv thaiv tau pom los ntawm Danish chemist Erik Christian Clemmensen (1876-1941) hauv 1913.
④ Kishner Wolff Huang Minglong kho dua tshiab
Aldehydes thiab ketones tuaj yeem hnov mob nrog anhydrous hydrazine los tsim hydrazones (C=NNHR), uas tuaj yeem decomposed rau hauv nitrogen gas los ntawm cua sov nrog anhydrous ethanol thiab sodium ethoxide nyob rau hauv siab - lub nkoj siab mus rau 180-200℃. Carbonyl pawg raug txo qis rau methylene pawg nyob rau hauv cov xwm txheej alkaline, thiab cov tshuaj tiv thaiv no hu ua Wolff Kishner txo cov tshuaj tiv thaiv.
Huang Minglong (1898-1979), tus kws tshuaj lom neeg muaj npe nrov hauv Suav teb thiab tus kws tshaj lij ntawm CAS Member, txhim kho cov tshuaj tiv thaiv. Cov txiaj ntsig siab dua tuaj yeem ua tiav los ntawm kev hloov cov dej tsis muaj dej hydrazine nrog cov tshuaj aqueous ntawm hydrazine. Ntawd yog, aldehyde lossis ketone, sodium hydroxide, aqueous tov ntawm hydrazine, thiab kub kub hnyav hnyav (diethylene glycol, diethylenegly clo, HOCH2CH2OCH2CH2OH) tau co rhuab los ua hydrazone, thiab tom qab ntawd ntau tshaj hydrazine thiab dej tau evaporated. Tom qab ncav cuag qhov decomposition kub ntawm hydrazone, cov tshuaj tiv thaiv tau refluxed kom tiav cov tshuaj tiv thaiv. Cov tshuaj tiv thaiv no hu ua Wolff Kishner Huang Minglong cov tshuaj tiv thaiv.
Noj acetaldehyde ua piv txwv, nws tuaj yeem txo qis rau ethane los ntawm Wolff Kishner thiab Wolff Kishner Huang Minglong cov tshuaj tiv thaiv, uas tsim nyog rau kev txo qis cov kua qaub carbonyl compounds.
(6) Hydrogen daim ntawv cog lus
Acetaldehyde tuaj yeem tsim hydrogen bonds hauv dej, uas yog lwm qhov laj thawj vim li cas acetaldehyde (qis aldehydes) yooj yim soluble hauv dej.
FAQ
Dab tsi yog qhov tsw ntawm acetaldehyde?
ACETALDEHYDE QHOV TSEEB LOS YOG SAU? Cov lus piav qhia txog kev hnov mob txuam nrog acetaldehyde muaj xws li ntsuab (Granny Smith) txiv apples, taub dag nqaij / noob, avocado unripe, thiab latex xim. Acetaldehyde yog qee yam tshwj xeeb hauv qhov no; tias "tus cwj pwm" ntawm nws cov aroma tuaj yeem hloov pauv raws li nws cov concentration hloov.
Cov mis rau acetaldehyde yog dab tsi?
Acetaldehyde - C2H4O
Acetaldehyde, ethanal, yog xim tsis muaj xim, dej -soluble, burnable kua uas muaj cov tshuaj formula C2H4O thiab cov qauv qauv CH3CHO. Acetaldehyde muaj qhov kub ntawm qhov kub ntawm 21 degrees.
Cov dej qab zib dab tsi muaj ntau hauv acetaldehyde?
Tsis tas li ntawd, acetaldehyde muaj nyob rau hauv cov dej haus xws li tshuaj yej thiab dej qab zib (0.2-0.6 ppm), npias (0.6-24 ppm), wine (0.7-290 ppm) thiab ntsuj plig (0.5-104 ppm) 2).
Cim npe nrov: Acetaldehyde CAS 75-07-0, lwm tus neeg, manufacturers, hoobkas, lag luam wholesale, yuav, nqe, tej, kev muag khoom