Qhov Tseem Ceeb - Hemiacetal vs Hemiketal
Qhov sib txawv tseem ceeb ntawm Hemiacetal thiab Hemiketal yog hemiacetal yog tsim los ntawm cov tshuaj tiv thaiv ntawm cawv thiab aldehyde whereas hemiketal yog tsim los ntawm cov tshuaj tiv thaiv ntawm cawv thiab ketone.
Hemiacetal thiab hemiketal yog cov organic tebchaw uas tuaj yeem pom zoo li hybrid molecules uas muaj ob pawg ua haujlwm hauv tib lub molecule; pawg hydroxyl thiab ib pawg ether.
Hemiacetal yog dab tsi?
Hemiacetal yog cov organic compound uas lub hauv paus carbon atom yog sib koom nrog plaub pawg sib txawv; -OR pab pawg, -OH pab pawg, -R pab pawg thiab -H pawg. Hemiacetal yog tsim los ntawm aldehyde. Hauv qhov sib piv, yog tias qhov sib xyaw no yog tsim los ntawm ketone, ces nws hu ua Hemiketal. Cov tshuaj formula ntawm Hemiacetal yog RHC (OH) LOSSIS '. Pawg "R" yog ib pawg alkyl.
Daim duab 01: Tsim ib qho Hemiacetal
Ib Hemiacetal yog tsim thaum muaj cawv ntxiv rau aldehyde. Hauv cov tebchaw hemiacetal, muaj ob hom kev sib txuas uas sawv cev rau ob qhov pib molecules ua rau tsim cov hemiacetal.
- The –C-O-H sawv cev rau cawv.
- Cov –C-O-R daim ntawv cog lus sawv cev rau pawg ether tsim los ntawm pawg carbonyl ntawm aldehyde.
Ib hemiacetal yog tsim thaum -OR pawg ntawm cawv tawm tsam carbon atom ntawm aldehyde.(-OR pawg yog tsim thaum lub hydrogen atom ntawm ROH cawv raug tso tawm). Cov pa roj carbon atom ntawm aldehyde muaj ib feem zoo nqi vim qhov sib txawv ntawm electronegativity qhov tseem ceeb ntawm cov pa roj carbon atom thiab cov pa atom hauv carbonyl pawg. Cov pa oxygen -OR pawg ntawm cawv tuaj yeem ua raws li nucleophile vim nws nplua nuj nrog cov khoom siv hluav taws xob. Qhov nucleophile no tawm tsam cov pa roj carbon atom ntawm cov pab pawg carbonyl ntawm aldehyde, ua rau muaj cov tshuaj tiv thaiv nucleophilic ntxiv. Qhov tshwm sim yog hemiacetal. Cov tshuaj tiv thaiv no tshwm sim hauv qhov nruab nrab acidic. Lwm txoj hauv kev tsim cov hemiacetal yog ib nrab hydrolysis ntawm acetal.
Hemiketal yog dab tsi?
Hemiketal yog cov organic compound uas lub hauv paus carbon atom yog sib koom nrog plaub pawg sib txawv; -OR pab pawg, -OH pab pawg, thiab ob -R pawg (ib yam zoo ib yam lossis txawv ntawm ib leeg). Ib qho hemiketal yog tsim los ntawm cov tshuaj tiv thaiv ntawm ib qho cawv thiab ketone. Cov tshuaj formula ntawm hemiketal yog R1R2C(OH)OR'. Tsis zoo li hauv hemiacetal, tsis muaj hydrogen atom ncaj qha sib txuas rau lub hauv paus carbon atom ntawm hemiketal.
Daim duab 02: Tsim ib tug Hemiketal
Cov pa roj carbon atom ntawm pawg carbonyl ntawm ketone muaj ib feem ntawm qhov zoo vim qhov sib txawv ntawm cov txiaj ntsig electronegative ntawm carbon atom thiab oxygen atom. Yog li ntawd, cov pa roj carbon atom no tau txais kev tawm tsam nucleophilic los ntawm pawg -OR los ntawm ib qho cawv. Cov -OR pawg ntawm cawv ua raws li nucleophile vim nws nplua nuj nrog electrons.
Qhov txawv ntawm Hemiacetal thiab Hemiketal yog dab tsi?
Hemiacetal vs Hemiketal |
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| Hemiacetal yog cov organic compound uas lub hauv paus carbon atom yog sib koom nrog plaub pawg sib txawv; -OR pab pawg, -OH pab pawg, -R pab pawg thiab -H pab pawg. | Hemiketal yog cov organic compound uas lub hauv paus carbon atom yog sib koom nrog plaub pawg sib txawv; -OR pab pawg, -OH pab pawg, thiab ob -R pab pawg (zoo ib yam lossis txawv ntawm ib leeg). |
| Ib hemiacetal yog tsim los ntawm cov tshuaj tiv thaiv ntawm cawv thiab aldehyde. | Ib hemiketal yog tsim los ntawm cov tshuaj tiv thaiv ntawm cawv thiab ketone. |
| Nyob ntawm Hydrogen Atom | |
| Hemiacetal muaj hydrogen atom ncaj qha sib txuas rau hauv nruab nrab carbon atom. | Tsis muaj hydrogen atom ncaj qha sib txuas rau lub hauv paus carbon atom ntawm hemiketal. |
| General Formula | |
| Cov tshuaj formula ntawm Hemiacetal yog RHC (OH) LOSSIS '. | Cov tshuaj formula ntawm hemiketal yog R1R2C(OH)OR'. |
Summary – Hemiacetal vs Hemiketal
Hemiacetal thiab hemiketal yog ob hom ntawm cov organic tebchaw uas muaj ob pawg ua haujlwm hauv tib lub molecule. Qhov txawv ntawm Hemiacetal thiab Hemiketal yog hemiacetal yog tsim los ntawm cov tshuaj tiv thaiv ntawm ib qho cawv thiab aldehyde whereas Hemiketal yog tsim los ntawm cov tshuaj tiv thaiv ntawm ib qho cawv thiab ketone.
