Synthesis ntawm Alkyl polyglycoside carbonates

Alkyl polyglycoside carbonates tau npaj los ntawm transesterification ntawm alkyl monoglycosides nrog diethyl carbonate (Daim duab 4).Nyob rau hauv qhov kev txaus siab ntawm kev sib xyaw ua ke ntawm cov reactants, nws tau ua pov thawj tias muaj txiaj ntsig zoo los siv cov khoom siv roj carbon diethyl carbonate ntau dhau kom nws ua haujlwm rau ob qho tib si ua cov khoom siv transesterification thiab hnyav.2Mole-% ntawm 50% sodium hydroxide tov yog ntxiv dropwise rau qhov sib tov nrog stirring ntawm ib ncig ntawm 120 ℃.Tom qab 3 teev nyob rau hauv reflux, cov tshuaj tiv thaiv sib tov yog tso cai rau txias rau 80 ℃ thiab neutralized nrog 85% phosphoric acid.Diethyl carbonate ntau tshaj yog distilled tawm hauv vacuo.Nyob rau hauv cov kev mob tshwm sim no, ib pawg hydroxyl zoo dua esterified.Qhov piv ntawm qhov seem educt rau cov khoom hauv 1: 2.5: 1 (monoglycoside: Monocarbonate: Polycarbonate).

Dhau li ntawm cov monocarbonate, cov khoom lag luam nrog cov qib siab ntawm kev hloov pauv kuj tau tsim hauv cov tshuaj tiv thaiv no.Lub degree ntawm carbonate ntxiv tuaj yeem tswj tau los ntawm kev tswj xyuas cov tshuaj tiv thaiv.Rau ib tug C₁₂ monoglycoside, ib qho kev faib tawm ntawm mono-, di- thiab tricarbonate ntawm 7: 3: 1 yog tau raws li cov tshuaj tiv thaiv tau piav qhia (Daim duab 5).Yog tias lub sijhawm tshuaj tiv thaiv tau nce mus rau 7 teev thiab yog tias 2moles ntawm ethanol raug distilled rau lub sijhawm ntawd, cov khoom tseem ceeb yog C.₁₂ monoglycoside dicarbonate.Yog tias nws tau nce mus rau 10 teev thiab 3moles ntawm ethanol raug distilled, cov khoom tseem ceeb thaum kawg tau txais yog tricarbonate.Qhov degree ntawm carbonate ntxiv thiab yog li qhov sib npaug ntawm hydrophilic / lipophilic ntawm alkyl polyglycoside compound tuaj yeem hloov kho yooj yim los ntawm kev hloov pauv ntawm lub sijhawm cov tshuaj tiv thaiv thiab lub ntim ntim.