Acetic anhydride: zog, kev npaj thiab kev siv

Anhydrides ntawm carboxylic acids - cov khoom ntawm lub cev qhuav dej ntawm lub lwg me me. Cov no yog yus muaj los ntawm isomerism biosoedineny radicals. Thaum tis npe carboxylic acid anhydrides feem ntau siv nomenclature keeb kwm (e.g., anhydride, acetic acid, maleic anhydride, etc.). Thaum lub sij hawm tas li ntawd ntawm carboxylic acids dehydrating agents (feem ntau phosphorus oxide) tshwm sim lawv lub cev qhuav dej, uas ua nyob rau hauv lub tsim ntawm carboxylic acid anhydrides.

Acetic anhydride: Kev npaj ntawm

Lub npe compound tau yuav muab ntxhua ua ob peb txoj kev. Rau nws cov synthesis feem ntau siv phosphorus oxide, uas yog ib tug heev muaj zog dehydrating neeg sawv cev. Nws tseem muaj lwm txoj kev rau lub synthesis ntawm anhydride. Piv txwv li, acetic anhydride yuav tau nyob rau hauv qhov kev txiav txim ntawm phosphate li cov acetate acid anhydride. Lub cua txias txheej txheem ntxiv dropwise SN3SOS1 ib particle ib particle dewatered thiab qhuav huv si acid-sodium acetate. Cov uas ua sib tov twb rhuab mob pesnrab thiab cov tsim acetic anhydride raug tshem tawm nyob rau hauv ib tug xuab zeb da dej thiab ces lim los ntawm distillation. Raws li ib tug tshwm sim ntawm cov lag luam ua xav losis kua acetate acid.

Acetic anhydride, thiab tsis tshua muaj-molecular tshuaj - kua nrog ib tug ntse tsw, suab insoluble nyob rau hauv dej, nkag soluble nyob rau hauv ntau organic tshuaj. Nws yuav tsum tau muab sau tseg tias anhydrides siab carboxylic acids (tshwj xeeb tshaj yog limiting) - khib nyiab ntxhiab. Lawv boiling kub ho ntau dua li cov coj carboxylic acids.

Acetic anhydride: Tshuaj khoom

Qhov no compound yog feem ntau siv rau ntau cov tswv cuab ntawm kawm txawv ntawm cov organic tshuaj los ntawm txoj kev ntawm cov organic synthesis. Nyob rau hauv cov tshuaj tiv thaiv ntawm lub anhydrides nrog dej mus muab ob tug molecules ntawm lub sib nug xov acid.

Amonoliz anhydrides ua mus rau tsim ntawm amides thiab ammonium ntsev ntawm lub sib nug xov carboxylic acids. Lub tshua siv rau muab alkoliza nrog anhydrides esters.

Acetal anhydride yog siv raws li lub dehydrating thiab acetylating neeg sawv cev nyob rau hauv cov txheej txheem atsetiltselyulozy, yas acetate, tshuaj, dimethylacetamide, colorants, uas muaj ntxhiab tshuaj, thiab lwm yam Acetate aldehyde yog irritating mus rau lub pa ib ntsuj av tau, ob lub qhov muag, thiab ua rau daim tawv nqaij kub nyhiab.

Cellulose acetate tau vim qhov kev txiav txim nyob rau hauv cellulose acetate anhydride nyob rau hauv lub xub ntiag ntawm ib lub hauv paus (acid sulphate). Uas ua tsis tiav acetylation npaj mono- thiab cellulose diacetates. Di- thiab cellulose triacetate siv nyob rau hauv qhuav ntawm acetate txhob lo lo ntxhuav. Rau lub hom phiaj no lawv yog yaj nyob rau hauv ib tug sib tov ntawm acetone thiab ethanol (85:15) los yog nyob rau hauv cov ntshiab acetone. Khov tshuaj yog tau uas yog extruded los ntawm tshwj xeeb cov ntxaij lim dej. Nyias ib daim hlab ntawm cov tshuaj qhuav li thiab tig mus rau hauv yarns, uas yog siv rau zus tau tej cov ntau yam ntawm xov ntawm cov khoom cua fibers.

Cov muaj daim ntaub ntawv uas yog siv thiab lwm yam anhydrides. Maleic anhydride - crystalline yeeb tshuaj, zoo soluble nyob rau hauv dej thiab nyob rau hauv acetone, melts ntawm 52,85 ° C. Feem ntau, qhov no cov ntaub ntawv uas yog npaj los ntawm maleic acid. Siv nyob rau hauv zus tau tej cov tshuaj tua kab, polyester thiab alkyd resins. Phthalic anhydride yog ua vim cov oxidation uas naphthalene. Cov yav tas yog siv rau cov synthesis ntawm kev loj hlob promoters, tshuaj tua kab, raws li zoo li ib co tshuaj. Phthalic anhydride - crystalline khoom nrog ib tug melting point ntawm 128 ° C. Hais tias anhydride yog siv los nrhiav tau Phenolphthalein (qhia thiab medicament). Qhov no anhydride yog siv rau qhov siv thiab ua tshuaj (dimethyl phthalate).