Qhov sib txawv tseem ceeb ntawm stereocenter thiab chiral chaw yog qhov chaw stereocenter yog ib qho taw qhia ntawm ib lub molecule uas tuaj yeem muab lub stereoisomer thaum ob pawg sib pauv ntawm qhov no thaum lub chaw chiral yog ib qho atom hauv ib lub molecule uas muaj peev xwm muab tau ib qho stereoisomer. enantiomer thaum ob pawg ntawm qhov chaw no sib pauv.
Ob lo lus stereocenter thiab chiral center feem ntau siv sib hloov vim tias txhua lub chaw chiral yog stereocenters; Txawm li cas los xij, tag nrho cov stereocenters tsis yog chiral chaw.
Stereocenter yog dab tsi?
Stereocenter yog ib qho taw tes hauv cov molecule uas tuaj yeem ua rau stereoisomers. Txawm li cas los xij, nws tsis tas yuav yog atom. Yog tias ob pawg ntawm cov atoms sib koom ua ke rau qhov no, nws muab ib qho stereoisomer. Stereoisomers yog cov molecules uas muaj tib lub qauv molecular thiab atomic txoj cai, tab sis txawv spatial kev npaj.
Stereocenters tseem hu ua stereogenic chaw. Yog tias lub stereocenter yog carbon atom, nws tuaj yeem yog sp2 hybridized lossis sp3 hybridized. Qhov no txhais tau hais tias lub stereocenter tuaj yeem muaj ob daim ntawv cog lus lossis ib daim ntawv cog lus, feem. Qee cov achiral molecules kuj muaj stereocenters. Piv txwv li, cis-trans isomers muaj stereocenters, tab sis feem ntau ntawm lawv tsis muaj chiral chaw.
Daim duab 1: Cis-trans Isomers ntawm Dichloroethene (I-cis isomer, II-trans isomer)
Cov molecules saum toj no tsis muaj chiral chaw. Tab sis lawv muaj stereocenters. Ob lub vinyl carbon atoms yog stereocenters (ob chav sib txuas carbon atoms). Qhov no yog vim tias thaum cov pab pawg txuas nrog cov pa roj carbon atom sib hloov, lawv ua rau isomers.
Chiral Center yog dab tsi?
Chiral center yog cov pa roj carbon atom uas plaub lub atoms sib txawv los yog pawg ntawm cov atoms sib txuas. Chiral compounds yog cov tshuaj uas muaj chiral carbon atoms. Nws yog ib qho tseem ceeb uas yuav tsum nco ntsoov tias cov cuab yeej ntawm muaj cov chaw chiral hu ua chirality. Lub chaw chiral yog qhov tseem ceeb sp3 hybridized vim tias nws yuav tsum tau dais plaub pawg sib txawv ntawm cov atoms, tsim plaub daim ntawv cog lus ib leeg.
Daim duab 2: Enantiomers nce vim muaj cov chaw chiral.
Chiral cov chaw ua rau qhov kho qhov muag isomerism ntawm cov tebchaw. Hauv lwm lo lus, cov tebchaw muaj cov chaw chiral tsis suav nrog nws daim iav duab. Yog li ntawd, lub compound uas muaj chiral centre thiab cov molecule uas zoo li nws daim iav duab yog ob lub tebchaw sib txawv. Ob lub molecules ua ke no hu ua enantiomers.
Qhov Zoo sib xws ntawm Stereocenter thiab Chiral Center yog dab tsi?
- Ob lub stereocenters thiab chiral centre muab nce rau stereoisomers.
- Txhua lub chaw chiral yog stereocenters, tab sis txhua lub stereocenters tsis yog chiral chaw.
Qhov txawv ntawm Stereocenter thiab Chiral Center yog dab tsi?
Stereocenter vs Chiral Center |
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| Stereocenter yog ib qho taw tes hauv cov molecule uas tuaj yeem ua rau stereoisomers. | Chiral center yog cov pa roj carbon atom uas muaj plaub lub atoms sib txawv los yog pawg atoms sib txuas. |
| Nature | |
| A stereocenter yog ib qho taw tes hauv lub molecule, tsis tas yuav yog atom. | Ib lub chaw chiral yog carbon atom. |
| hybridization ntawm carbon | |
| Yog stereocenter yog carbon atom, nws tuaj yeem yog sp2 hybridized lossis sp3 hybridized. | Chiral chaw yog qhov tseem ceeb sp3 hybridized. |
| Groups of Atoms | |
| Cov chaw sib tham tuaj yeem muaj peb lossis plaub pawg txuas nrog nws. | Chiral chaw tseem ceeb muaj plaub pawg txuas rau nws. |
| Tshuaj Bonds | |
| Stereocenter tuaj yeem muaj ib daim ntawv cog lus lossis ob daim ntawv cog lus nyob ib puag ncig nws. | Chiral chaw zov me nyuam tsuas muaj ib daim ntawv cog lus nyob ib ncig ntawm nws. |
| Results of Interchanging Groups | |
| Kev sib pauv ntawm pab pawg ntawm stereocenter cov ntaub ntawv stereoisomers. | Kev sib pauv ntawm pab pawg ntawm chiral center cov ntaub ntawv enantiomers. |
Summary – Stereocenter vs Chiral Center
Txhua lub chaw chiral yog qhov chaw nruab nrab, tab sis txhua lub stereocenters tsis yog chiral chaw. Lub stereocenter yog ib qho taw tes ntawm cov molecule uas tuaj yeem muab lub stereoisomer thaum ob pawg sib pauv ntawm qhov chaw no thaum lub chaw chiral yog ib qho atom hauv cov molecule uas tuaj yeem muab cov enantiomer thaum ob pawg ntawm qhov chaw no sib hloov. Qhov no yog qhov sib txawv tseem ceeb ntawm stereocenter thiab chiral center.
Image Courtesy:
1. “Dichloroethene” Los Ntawm V8rik – en:Image:Dichloroethene-p.webp
2. "Thalidomide-enantiomers" Los ntawm Klaus Hoffmeier - Tus kheej ua haujlwm (Public Domain) ntawm Commons Wikimedia
