Qhov sib txawv tseem ceeb ntawm E thiab Z isomers yog tias E isomers muaj cov neeg hloov pauv nrog qhov tseem ceeb dua nyob rau sab nraud whereas Z isomers muaj cov neeg hloov pauv nrog qhov tseem ceeb dua ntawm tib sab.
Tus E-Z nomenclature yog lub cim sau npe rau cov isomers sib txawv uas muaj cov qauv tshuaj tib yam, tab sis sib txawv spatial kev npaj. Tsis tas li ntawd, E thiab Z isomers yog alkenes. Cov isomers tau txais lawv lub npe raws li txoj haujlwm ntawm cov neeg hloov pauv txuas nrog ob daim ntawv cog lus ntawm alkene.
E Isomers yog dab tsi?
Cov E isomers yog alkenes muaj cov neeg hloov pauv nrog qhov tseem ceeb dua nyob rau sab nraud ntawm ob daim ntawv cog lus. Tsab ntawv "E" los ntawm entgegen hauv German, uas txhais tau tias "tawm tsam". Lub hauv paus ntawm E-Z sau ntawv yog ib txheej ntawm cov cai hu ua cov cai tseem ceeb. Lawv yog Cahn-Ingold-Prelog (CIP) cov cai. Cov no yog cov txheej txheem rau npe cov organic molecules, kom qhia lawv tsis sib npaug.
Cov kauj ruam ntawm kev sau npe molecule siv CIP cov cai yog raws li hauv qab no;
- Txheeb xyuas cov chaw chiral lossis ob daim ntawv cog lus tam sim no hauv cov molecule.
- Txiav txim siab qhov tseem ceeb ntawm cov neeg hloov pauv txuas nrog lub chaw chiral lossis ob daim ntawv cog lus.
- Siv R / S system lossis E / Z system los ua lub npe sib xyaw.
Qhov tseem ceeb ntawm cov neeg hloov pauv
- Ua ntej xav txog cov atoms ncaj qha rau ntawm qhov chaw chiral lossis ob daim ntawv cog lus - siab dua tus lej atomic, qhov tseem ceeb dua
- Yog tias muaj cov atoms sib npaug tam sim no, ces muaj kev khi. Tom qab ntawd xyuas cov pab pawg hloov pauv kom pom qhov sib txawv ntawm tus lej atomic.
- Yog tseem muaj txoj hlua khi, xav txog cov atoms sib txuas rau txhua lub atoms hauv cov saw tseem ceeb thiab xyuas seb puas muaj qhov sib txawv.
Daim duab 01: E-Z nomenclature ntawm 3-methylpent-2-ene
Hauv daim duab saum toj no, E isomer muaj qhov tseem ceeb hloov pauv nyob rau sab nraud ntawm ob daim ntawv cog lus thaum Z isomer muaj cov neeg hloov pauv ntawm tib sab.
Thaum txiav txim siab qhov tseem ceeb ntawm cov khoom hloov, ua ntej xav txog cov atoms ncaj qha rau daim ntawv cog lus ob npaug; Hauv qhov piv txwv saum toj no, muaj peb Carbon atoms (C) thiab ib qho hydrogen atom (H). Yog li ntawd, muaj kev khi vim tias ib qho ntawm ob lub vinyl carbon atoms (carbon atoms nyob rau hauv ob daim ntawv cog lus) muaj ncaj qha bonded carbon atoms. Tom qab ntawd, txhawm rau txiav txim siab cov pab pawg tseem ceeb, xav txog cov atom uas tuaj tom qab cov carbon atoms ncaj qha sib txuas. Txij li cov pab pawg hloov pauv txuas nrog cov vinyl carbon no yog pawg methyl (-CH 3) thiab ib pawg ethyl (-CH2CH 3), qhov tseem ceeb yog muab rau pawg ethyl. Qhov ntawd yog vim hais tias cov atom los tom qab cov pa roj carbon monoxide ncaj qha (sib koom ncaj qha rau cov vinyl carbon) yog hydrogen atom hauv methyl pawg thiab cov pa roj carbon hauv pawg ethyl.
Z Isomers yog dab tsi?
Z isomers yog alkenes muaj cov neeg hloov pauv nrog qhov tseem ceeb dua nyob rau tib sab ntawm ob daim ntawv cog lus. Tsab ntawv "Z" los ntawm zusammen hauv German, uas txhais tau tias "ua ke".
Daim duab 02: E-Z nomenclature ntawm 2-butene
Hauv daim duab saum toj no, cov neeg hloov pauv uas muaj qhov tseem ceeb yog nyob rau tib sab ntawm ob daim ntawv cog lus hauv Z isomer whereas E isomer muaj cov neeg hloov pauv nyob rau sab nraud. Tsis tas li ntawd, CIP cov cai txiav txim siab qhov tseem ceeb ntawm cov neeg hloov pauv no. Rau qhov piv txwv saum toj no, cov atoms ncaj qha sib txuas rau ob chav sib koom ua ke yog Carbon atoms (C) ntawm methyl pawg thiab hydrogen atoms (H). Txij li thaum carbon atom (14) muaj tus lej atomic siab thaum piv nrog hydrogen (1), qhov tseem ceeb tshaj plaws yog rau pawg methyl (-CH 3).
Qhov txawv ntawm E thiab Z Isomers yog dab tsi?
E Isomers vs Z Isomers |
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| E isomers yog alkenes muaj cov neeg hloov pauv nrog qhov tseem ceeb dua nyob rau sab nraud ntawm ob daim ntawv cog lus. | Z isomers yog alkenes muaj cov hloov pauv nrog qhov tseem ceeb dua nyob rau tib sab ntawm ob daim ntawv cog lus. |
| Lub ntsiab lus ntawm Nomenclature | |
| Tsab ntawv "E" los ntawm entgegen hauv German, uas txhais tau tias "tawm tsam". | Tsab ntawv "Z" los ntawm zusammen hauv German, uas txhais tau tias "ua ke". |
| Kev sib raug zoo nrog lwm cov npe | |
| E isomers ntawm alkenes belongs rau trans isomer qeb. | Z isomers ntawm alkenes belongs rau cis isomer qeb. |
Summary – E vs Z Isomers
E-Z sau lossis nomenclature yog siv rau lub npe isomers uas muaj tib lub qauv molecular thiab spatial qauv, muab txhua isomer ib qho tshwj xeeb. Qhov sib txawv ntawm E thiab Z isomers yog tias E isomers muaj cov neeg hloov pauv uas muaj qhov tseem ceeb dua nyob rau sab nraud thaum Z isomers muaj cov neeg hloov pauv nrog qhov tseem ceeb dua ntawm tib sab.
