N, N-dimethylformamideyog ib qho organic compound nrog cov tshuaj formula C3H7NO. Nws yog cov kua uas tsis muaj xim tsis muaj pob tshab. Nws yog miscible nrog dej thiab yog miscible nrog feem ntau cov organic solvents. Nws tsis yog tsuas yog siv dav siv tshuaj raw khoom, tab sis kuj yog siv dav siv cov kuab tshuaj zoo heev. Ntxiv nrog rau halogenated hydrocarbons, nws tuaj yeem tov nrog dej thiab cov kuab tshuaj organic feem ntau ntawm qhov xav tau, thiab muaj kev solubility zoo rau ntau yam organic thiab inorganic compounds.
Peb yog ib lub Hoobkas ntawm ntshiab N, N-dimethylformamide, yog li peb tau ua kev ntsuas thiab tshawb fawb txog cov khoom ntawm cov khoom no. Thaum peb muag n, N-dimethylformamide, peb teeb tsa tus nqi tsim nyog tshaj plaws ntawm N, N-dimethylformamide thiab zoo tshaj plaws ntawm N, N-dimethylformamide. Piav txog nws qhov xwm txheej.
Chemical Property:
1. Nws yog ib qho aprotic polar solvent, uas muaj zoo solubility rau ntau cov organic thiab inorganic tebchaw, thiab muaj cov tshuaj zoo stability thaum tsis muaj alkali, acid thiab dej.
2. Cov khoom siv tshuaj lom neeg: thaum tsis muaj kua qaub, alkali thiab dej, nws yog qhov ruaj khov txawm tias thaum tshav kub kub rau qhov kub. Nws yog decomposed rau hauv formic acid thiab dimethylamine nyob rau hauv qhov kev txiav txim ntawm acid, thaum nws yog decomposed rau hauv formate thiab dimethylamine nyob rau hauv qhov kev txiav txim ntawm lub hauv paus.
3. Nws yog decomposed rau hauv dimethylamine thiab formaldehyde nyob rau hauv qhov kev txiav txim ntawm ultraviolet rays, thiab ces decomposed rau hauv dimethylamine thiab carbon monoxide thaum rhuab mus txog 350 degree . Nws tsim ib qho kev ruaj khov equimolar adduct nrog hydrochloric acid, nrog lub melting point ntawm 40 degree C thiab lub boiling point ntawm 110 ° C. Nws kuj muaj peev xwm tsim crystalline adducts nrog SO3, nrog ib tug melting point ntawm 138 ° C thiab ib tug boiling point. 145 degree C. dmf-so3 tuaj yeem siv los ua cov tshuaj sulfonating me me thiab sulfating tus neeg sawv cev. Cov adducts tsim nrog POCl3, CoCl2, SOCl2, thiab lwm yam tuaj yeem qhia Cho pawg ntawm cov nplhaib uas muaj ntxhiab nrog cov khoom siv hluav taws xob siab (Vilsmeier cov tshuaj tiv thaiv). P2O5 yog insoluble nyob rau hauv N, N-dimethylformamide ntawm chav tsev kub, tab sis nws muaj peev xwm yaj nyob rau hauv chav tsev kub yam tsis muaj nag lossis daus tom qab tsim ib tug ruaj khov complex saum toj no 40 degree. Thaum rhuab nyob rau hauv lub xub ntiag ntawm metallic sodium, ib tug tsausmuag cov tshuaj tiv thaiv tshwm sim thiab hydrogen gas tawm. Nws tuaj yeem cuam tshuam hnyav nrog triethylaluminium ntawm 0 degree. Nws kuj tseem tuaj yeem ua rau Grignard reagent. Thaum reacting nrog acyl chloride thiab anhydride, ib tug derivative ntawm dicarbonamide yog tsim.
4. Nws belongs rau tsawg toxicity. Kev sim tsiaj txhu pom tau tias kev tswj hwm tas li ntawm N, N-dimethylformamide ua rau poob phaus thiab cuam tshuam kev ua haujlwm hematopoietic. Nws muaj qhov ua kom khaus khaus ntawm qhov muag, tawv nqaij thiab mucosa, thiab nws cov kua lossis vapor tuaj yeem ua rau lub siab tsis zoo tom qab nqus los ntawm daim tawv nqaij. Inhalation ntawm high concentration ntawm vapor yuav ua rau mob lom. Cov tsos mob tseem ceeb yog khaus khaus heev, spasm dav dav, mob cem quav, xeev siab thiab ntuav. Ntxiv nrog rau cov tawv nqaij thiab mucous daim nyias nyias, cov tshuaj lom muaj xws li xeev siab, ntuav, hauv siab nruj, mob taub hau, tsis xis nyob, tsis qab los noj mov, mob plab, cem quav, hepatomegaly thiab daim siab ua haujlwm hloov, thiab urobilinogen thiab urobilin tuaj yeem nce ntxiv. Thaum siv, qhov nruab nrab vapor concentration yuav tsum qis dua 29.9mg / m3, thiab cov tsos mob lom (kev raug mob hauv nruab nrab ntawm lub paj hlwb) tshwm sim thaum qhov concentration yog 59.8mg / m3. Qhov ncauj toxicity LD50 ntawm nas thiab nas yog 3000-7000mg / kg. Qhov nruab nrab olfactory concentration yog 0.14mg / m3, thiab TJ 36-79 teev tias qhov siab tshaj plaws tso cai nyob rau hauv huab cua ntawm lub rooj cob qhia yog 10mg / m3.
5. Stability: ruaj khov
6. Cov khoom txwv tsis pub muaj: muaj zog oxidant, acyl chloride, chloroform, muaj zog reductant, halogen, chlorinated hydrocarbon, concentrated sulfuric acid thiab fuming nitric acid
7. Polymerization txaus ntshai: tsis yog polymerization.
Txij li thaum thawj synthesis ntawm dimethylformamide nrog formic acid thiab dimethylamine nyob rau hauv 1899, cov txheej txheem ntawm synthesizing dimethylformamide nrog txawv raw cov ntaub ntawv tau tsim, xws li dimethylamine carbon monoxide txoj kev, formamide dimethylamine txoj kev, cyanohydric acid methanol txoj kev, acetonitrile methanol formate, methyl formate. txoj kev dimethylamine, trichloroacetal dimethylamine txoj kev, thiab lwm yam. Txawm li cas los xij, kev lag luam ntau lawm txawv teb chaws yog tseem dominated los ntawm dimethylamine carbon monoxide txoj kev.
1. Methyl formate dimethylamine txoj kev: methyl formate yog tsim los ntawm esterification ntawm formic acid thiab methanol, thiab ces reacted nrog dimethylamine nyob rau hauv roj theem los ua dimethylformamide. Tom qab ntawd, methanol thiab unreacted methyl formate yog zoo los ntawm distillation, thiab cov khoom tiav yog npaj los ntawm lub tshuab nqus tsev rectification.
2. Dimethylamine carbon monoxide txoj kev: nws tau los ntawm cov tshuaj tiv thaiv ncaj qha ntawm dimethylamine thiab carbon monoxide nyob rau hauv qhov kev txiav txim ntawm sodium methoxide. Cov kev mob tshwm sim yog 1.5-2.5mpa thiab 110-150 degree . Cov khoom nyoos yog kho kom tau txais cov khoom tiav.
3. Methyl formate yog tsim los ntawm carbonylation ntawm carbon monoxide thiab methanol nyob rau hauv siab thiab kub ntawm 80-100 degree, thiab ces reacts nrog dimethylamine los tsim dimethylformamide, thiab cov khoom tiav yog tau tom qab rectification.
4. Trichloroacetal txoj kev: nws tau los ntawm reacting trichloroacetal nrog dimethylamine.
Ntxiv chloroform thiab {{0}}.52 qhov chaw ntawm Trichloroacetaldehyde mus rau hauv cov tshuaj tiv thaiv kettle, txias kom qis dua 30 degree, thiab tom qab ntawd qhia cov roj dimethylamine. Nyob rau tib lub sijhawm, poob 0.78 feem ntawm Trichloroacetaldehyde rau hauv cov tshuaj tiv thaiv kab mob rau cov tshuaj tiv thaiv. Tom qab cov tshuaj tiv thaiv tiav lawm, kev ua haujlwm distillation yog nqa tawm. Thaum qhov kub ntawm sab saum toj ntawm lub rectification kem yog 58-64 degree, cov feem yog chloroform, thiab cov feem ntawm 64-150 degree yog cov sib tov ntawm chloroform thiab dimethylformamide. Cov sib tov yog distilled nyob rau hauv lub siab txo kom tau crude dimethylformamide, thiab ces cov crude siv lead ua yog rectified kom tau cov khoom tiav.
Kev siv quota (kg / T): dimethylamine (40 feem pua) 2372; Trichloroacetaldehyde (95 feem pua) 2543.
Refining method: n, N-dimethylformamide feem ntau muaj impurities xws li dej, ethanol, thawj amine thiab secondary amine, thiab tuaj yeem tsim hcon (CH3) 2 · 2H2O nrog 2 molecules dej. Txhawm rau kom tau txais cov khoom lag luam siab purity, txoj kev sib xyaw desiccant thiab distillation tuaj yeem siv. Ua ntej, 1/10 ntim ntawm benzene tau ntxiv thiab azeotropic distillation tau ua nyob rau hauv ib txwm siab kom tshem tawm dej. Thiab tom qab ntawd refined raws li cov hauv qab no:
① Ntxiv anhydrous magnesium sulfate (25g / L) kom qhuav thiab distilled nyob rau hauv txo siab ntawm 2 ~ 2.67kpa.
② Ntxiv cov hmoov barium oxide, ncuav tawm cov kua tom qab nplawm, thiab distilled nyob rau hauv lub siab txo.
③ Ntxiv alumina hmoov (50}g / L, raug rho tawm haujlwm ntawm 500 ~ 600 degree), sib tov thiab co, thiab distilled nyob rau hauv lub siab txo (0.67 ~ 1.33kpa).
④ Ntxiv triphenylchlorosilane (5 ~ 10g / L), tshav kub ntawm 120 ~ 140 degree rau 24 teev, thiab tom qab ntawd distilled nyob rau hauv lub siab txo (0. 67 hli). Kev ua tau zoo ntawm cov khoom tau los ntawm txoj kev saum toj no: (1) ({{20}}.9 ~ 1.5) × 10 -7 S / m; (2) (0.4~1.0) × 10 -7 S/m; (3) (0.3 ~ 0.9) × 10 -7 S/m; (4) (0.2 ~ 0.5) × 10 -7 S/m.
5. Cov reagent dimethylformamide tau txais los ntawm cov khoom lag luam dimethylformamide los ntawm kev ua kom huv. Yog tias muaj dej me me hauv cov khoom lag luam, nws tuaj yeem raug tshem tawm los ntawm 4A molecular sieve. Yog tias cov ntsiab lus noo noo siab, qhov tsim nyog ntawm granular potassium hydroxide tuaj yeem ntxiv yam tsis tau co thiab tag nrho sawv ntsug rau txheej txheej. Tom qab sib cais cov dej txheej uas muaj formic acid thiab lwm yam impurities, ntxiv 1/5 ntawm reagent qib benzene nyob rau hauv lub ntim ntawm dimethylformamide rau atmospheric rectification. Thaum cov roj theem kub nce mus txog 130 degree, ntxiv qhov tsim nyog ntawm phosphorus pentoxide rau cov kua seem, npog thiab co rau 3.5H, lim tawm cov khoom tom qab sawv, thiab tom qab ntawd lub cev qhuav dej nrog cov poov tshuaj hydroxide nyob rau hauv nitrogen filling, ces, nyob rau hauv kev tiv thaiv. ntawm qhuav nitrogen, lub tshuab nqus tsev rectification yog nqa tawm mus sau nruab nrab distillate kom tau ib tug high-purity khoom.
6. Dimethylamine thiab carbon dioxide yog synthesized nyob rau hauv siab nyob rau hauv lub catalysis ntawm sodium methoxide, los yog dimethylamine thiab methyl formate yog npaj los ntawm roj theem cov tshuaj tiv thaiv, los yog dimethylamine thiab Trichloroacetaldehyde kuj npaj.