2, 5-Dihydroxybenzaldehydeyog ib qho organic compound nrog cov mis molecular C7H6O3 thiab CAS 1194-98-5. Nws yog ib lub teeb daj crystalline daim ntawv, feem ntau muaj nyob rau hauv hmoov los yog siv lead ua daim ntawv, nrog ib tug tshwj xeeb aldehyde saj, zoo li cov tsw ntawm iab almonds. Thaum lub sij hawm melting txheej txheem, nws yuav maj mam tig daj thiab sublimate ntawm kub kub. Nws tuaj yeem soluble hauv dej, tab sis nws cov solubility tsis siab. Nws kuj yog me ntsis soluble hauv cov kuab tshuaj organic xws li cawv thiab ethers. Cov tshuaj no muaj cov nplhaib benzene, pawg aldehyde, thiab pawg hydroxyl. Ntawm lawv, pawg aldehyde nyob rau ntawm qhov chaw nyob ib sab ntawm lub nplhaib benzene, thiab ob pawg hydroxyl nyob ntawm qhov nruab nrab ntawm lub nplhaib benzene. Nws yog ib qho kev txo qis uas tuaj yeem hnov mob nrog alkali los tsim cov phenolic ntsev. Nws tuaj yeem raug benzoin condensation cov tshuaj tiv thaiv nrog acetaldehyde nyob rau hauv acidic tej yam kev mob, ua benzoic acid. Tsis tas li ntawd, nws tuaj yeem ua rau muaj kev cuam tshuam nucleophilic ntxiv nrog ammonia lossis amine compounds. Muaj ntau yam kev siv nyob rau hauv kev npaj ntawm benzoin, nrog rau raws li ib tug aldehyde qhov chaw, tiv thaiv, condensation tus neeg sawv cev, impurity tshem tawm, catalyst, hnyav, pre-kho raw khoom, hloov kho cov qauv, thiab synthesis ntawm analogues. Cov kev siv no ua rau cov khoom lag luam tseem ceeb thiab tseem ceeb hauv cov txheej txheem ntawm kev npaj benzoin.
2, 5-Dihydroxybenzaldehyde yog ib qho tseem ceeb ntawm cov organic sib xyaw nrog cov qauv molecular tshwj xeeb.
(Cov khoom txuas:https://www.bloomtechz.com/synthetic-chemical/organic-intermediates/2-5-dihydroxybenzaldehyde-cas-1194-98-5.html)
Molecular configuration: Kev teeb tsa ntawm 2,5-Dihydroxybenzaldehyde molecules yog cov qauv qauv. Qhov no yog vim muaj rau carbon atoms thiab ob hydroxyl oxygen atoms ntawm nws lub nplhaib benzene yog coplanar. Cov qauv qauv no muab cov molecules ruaj khov dua hauv qhov chaw.
Bond lub kaum sab xis thiab daim ntawv cog lus ntev: Hauv 2,5-Dihydroxybenzaldehyde molecules, daim ntawv cog lus ntev ntawm cov pa roj carbon ib leeg yog kwv yees li 1.54 angstroms, daim ntawv cog lus ntev ntawm carbon hydrogen bonds yog li 1.09 angstroms, thiab Qhov ntev ntawm cov pa oxygen hydrogen bonds yog hais txog 0.97 angstroms. Cov ntawv cog lus ntev no nyob rau hauv qhov kev xav tau, muaj kev cuam tshuam cov khoom sib txuas ib txwm muaj.
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Hydrogen bonding thiab intramolecular kev sib cuam tshuam: 2, 5-Dihydroxybenzaldehyde molecules muaj ob pawg hydroxyl uas tuaj yeem ua raws li hydrogen bond pub lossis txais. Tshwj xeeb, hydrogen bonds tuaj yeem tsim los ntawm hydrogen atoms ntawm hydroxyl pawg thiab cov carbonyl oxygen atoms uas nyob ib sab hauv cov molecule, txhim khu kev ruaj ntseg ntawm cov molecule. Tsis tas li ntawd, muaj lwm yam kev sib tshuam intramolecular, xws li van der Waals rog thiab π - π kev sib cuam tshuam.
Electron huab faib thiab nqi faib khoom: Los ntawm kev suav thiab kev sim, cov khoom siv hluav taws xob huab cua faib thiab nqi faib ntawm 2,5-Dihydroxybenzaldehyde molecules tuaj yeem tau. Cov ntaub ntawv no muaj kev cuam tshuam cov electron ceev thiab them ceev ntawm cov molecules nyob rau hauv txawv cheeb tsam, uas yuav pab kom nkag siab txog cov hluav taws xob khoom thiab tshuaj reactivity ntawm molecules.
Infrared thiab Raman spectroscopy tsom xam: Los ntawm infrared thiab Raman spectroscopy cov tswv yim, nqus thiab tawg cov ntaub ntawv ntawm 2,5-Dihydroxybenzaldehyde molecules thaum vibration tuaj yeem tau. Cov ntaub ntawv no muaj feem xyuam nrog cov qauv thiab cov khoom siv tshuaj lom neeg ntawm cov khoom siv molecules, thiab tuaj yeem siv los txheeb xyuas cov qauv vibrational ntawm cov molecules, txiav txim siab hom thiab lub zog ntawm cov khoom siv tshuaj lom neeg, thiab lwm yam.
X-ray crystallographic tsom xam: X-ray crystallography yog ib txoj kev ncaj qha tau txais cov ntaub ntawv qauv molecular. Los ntawm kev sau cov ntaub ntawv X-ray diffraction, cov qauv peb-dimensional ntawm 2,5-Dihydroxybenzaldehyde molecules tuaj yeem txheeb xyuas. Txoj kev no tuaj yeem muab cov ntaub ntawv xws li kev ncua deb, lub kaum sab xis, thiab dihedral lub kaum sab xis ntawm atoms hauv molecules, uas yog qhov tseem ceeb rau kev nkag siab txog kev teeb tsa, kev sib haum xeeb, thiab tshuaj lom neeg ntawm cov molecules.
Nuclear magnetic resonance (NMR) spectroscopy tsom xam: NMR spectroscopy yog ib txoj hauv kev siv los tshuaj xyuas cov qauv molecular. Los ntawm kev sau NMR cov cim los ntawm ntau hom nuclear (xws li hydrogen, carbon, nitrogen, thiab lwm yam), cov ntaub ntawv xa tawm, tshuaj ib puag ncig, thiab kev sib txuas ntawm hom sib txawv ntawm cov atoms hauv cov molecule tuaj yeem tau. Rau 2,5-Dihydroxybenzaldehyde molecules, lawv cov qauv tuaj yeem tshawb xyuas ntxiv los ntawm hydrogen spectroscopy, carbon spectroscopy, thiab lwm yam kev qhia txog kev ntsuas thiab tshuaj xyuas.
2,5-Dihydroxybenzaldehyde muaj ntau yam siv hauv kev npaj benzoin.
1. Kev tshawb fawb lub hom phiaj: Hauv kev tshawb fawb txog kev sib txuas thiab cov khoom ntawm benzoin, 2, 5-Dihydroxybenzaldehyde kuj yog ib qho tseem ceeb ntawm kev sim tshuaj reagent. Los ntawm kev siv nws thiab lwm yam kev sim tshuaj reagents, nws yooj yim los ua cov kev sim ua ke thiab kev tshawb fawb txog kev siv tshuab.
2. Aldehyde tiv thaiv tus neeg sawv cev: Nyob rau hauv cov txheej txheem ntawm synthesizing benzoin, 2, 5-Dihydroxybenzaldehyde kuj tseem siv tau los ua tus neeg sawv cev tiv thaiv rau pawg aldehyde. Vim tias cov pab pawg aldehyde yog cov pab pawg ua haujlwm tau yooj yim oxidized los yog hnov mob nrog lwm cov tebchaw, kev siv 2,5-Dihydroxybenzaldehyde tuaj yeem tiv thaiv cov pab pawg aldehyde thiab txhim kho kev ua haujlwm thiab tawm los ntawm kev sib txuas.
3. Condensing agent: 2, 5-Dihydroxybenzaldehyde tuaj yeem siv los ua tus neeg sawv cev condensing hauv kev sib txuas ntawm benzoin. Nyob rau hauv cov tshuaj tiv thaiv condensation, nws tuaj yeem hnov mob nrog lwm qhov sib xyaw ua ke los tsim cov khoom siv tshiab, xws li Knoevenagel condensation nrog benzaldehyde los tsim benzoic acid.
4. Tshem tawm impurities: Nyob rau hauv cov txheej txheem ntawm synthesizing benzoin, feem ntau muaj ib co impurities, xws li unreacted raw khoom thiab by-products. Kev siv 2,5-Dihydroxybenzaldehyde tuaj yeem yooj yim tshem tawm cov impurities thiab txhim kho cov purity thiab zoo ntawm cov khoom.
5. Catalyst: 2, 5-Dihydroxybenzaldehyde tuaj yeem siv los ua ib qho catalyst rau cov synthesis ntawm benzoin. Los ntawm kev siv cov catalysts, cov tshuaj tiv thaiv tuaj yeem nrawm dua, thiab cov txiaj ntsig thiab cov khoom zoo tuaj yeem txhim kho.
6. Cov kuab tshuaj: 2,5-Dihydroxybenzaldehyde tuaj yeem siv los ua cov kuab tshuaj hauv cov synthesis ntawm benzoin. Nws tuaj yeem yaj qee cov khoom siv tsis zoo lossis cov khoom lag luam, txhim kho kev ua haujlwm ntawm cov tshuaj tiv thaiv.
7. Cov khoom siv kho mob ua ntej: Ua ntej ua ke benzoin, 2, 5-Dihydroxybenzaldehyde tuaj yeem siv los kho cov khoom siv ua ntej. Piv txwv li, nws tuaj yeem cuam tshuam nrog cov khoom siv raw los tsim cov khoom nruab nrab xws li semi acetals lossis acetals, ua kom yooj yim rau cov kauj ruam tom ntej.
8. Kev hloov kho cov qauv: Los ntawm kev siv 2, 5-Dihydroxybenzaldehyde ua tus hloov kho, kev hloov kho tshwj xeeb tuaj yeem ua rau cov qauv ntawm benzoin. Piv txwv li, lwm pab pawg ua haujlwm tuaj yeem raug qhia lossis txoj haujlwm ntawm cov neeg hloov pauv tuaj yeem hloov pauv.
9. Synthetic analogues: 2,5-Dihydroxybenzaldehyde tuaj yeem siv tau yooj yim los ua ke qee qhov sib txuas zoo ib yam li benzoin. Cov tebchaw no muaj cov khoom zoo sib xws thiab siv rau benzoin, tab sis tej zaum yuav muaj cov qauv sib txawv me ntsis.
Cov kauj ruam ntxaws ntxaws rau kev npaj 2,5-Dihydroxybenzaldehyde los ntawm cov tshuaj tiv thaiv condensation ntawm phenol thiab acrolein yog raws li nram no:
1. Ntxiv phenol thiab acrolein rau hauv lub khob ntim hauv qab, tom qab ntawd ntxiv qhov tsim nyog ntawm sodium hydroxide tov, do thiab maj mam ua kom sov cov tshuaj tiv thaiv rau lub xeev reflux. Lub sijhawm no, phenol thiab acrolein tau txais cov tshuaj tiv thaiv condensation nyob rau hauv alkaline tej yam kev mob los tsim 2, 5-dihydroxyphenylacrolein.
2. Tom qab cov tshuaj tiv thaiv tiav lawm, txias cov tshuaj tiv thaiv rau hauv chav sov, thiab tom qab ntawd ntxiv ib qho kev tsim nyog ntawm cov concentrated hydrochloric acid kom pH tus nqi ntawm cov tshuaj acidic.
3. Ntxuav cov txheej txheem saum toj kawg nkaus nrog cov tshuaj sodium carbonate hauv qhov sib cais kom tshem tawm cov phenol thiab acrolein uas tsis muaj kev cuam tshuam, thiab tom qab ntawd ua kem chromatography cais thiab ntxuav cov khoom 2, 5-Dihydroxybenzaldehyde.
Chemical Equation:
C6H5OH + CH2=CHO → C6H5(OH)CH=CHO
C6H5(OH)CH=CHCHO + HCl → C6H5(OH)CH=CHCOOH + HCl
C6H5(OH)CH=CHCOOH → C6H5(OH)CHO + H2O
Hauv cov txheej txheem synthesis saum toj no, thawj kauj ruam yog los tsim 2,5-dihydroxyphenylacrolein los ntawm cov tshuaj tiv thaiv condensation ntawm phenol thiab acrolein nyob rau hauv alkaline tej yam kev mob; Cov kauj ruam thib ob yog ntxiv cov concentrated hydrochloric acid kom tau txais cov tshuaj tiv thaiv acidolysis ntawm cov tsim tawm 2,5-dihydroxybenzaldehyde los tsim 2,5-Dihydroxybenzaldehyde thiab dej.