Qhov txawv ntawm Claisen thiab Dieckmann Condensation

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Qhov txawv ntawm Claisen thiab Dieckmann Condensation
Qhov txawv ntawm Claisen thiab Dieckmann Condensation

Video: Qhov txawv ntawm Claisen thiab Dieckmann Condensation

Video: Qhov txawv ntawm Claisen thiab Dieckmann Condensation
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Qhov sib txawv tseem ceeb ntawm Claisen thiab Dieckmann condensation yog Claisen condensation cov tshuaj tiv thaiv yog ib hom kev sib txuas cov tshuaj tiv thaiv whereas Dieckmann condensation cov tshuaj tiv thaiv yog ib hom kev tsim lub nplhaib.

Cov tshuaj tiv thaiv condensation hauv chemistry yog cov tshuaj tiv thaiv uas muaj cov dej molecule los yog cawv yog tsim los ntawm cov tshuaj tiv thaiv. Cov dej / cawv molecule no yog tsim los ntawm kev sib xyaw ntawm hydrogen atom thiab ib pawg -OH, uas yog los ntawm ob lub molecules sib txawv uas cuam tshuam nrog ib leeg.

Claisen Condensation yog dab tsi?

Claisen condensation yog ib hom kev sib txuas cov tshuaj tiv thaiv uas muaj cov pa roj carbon-carbon daim ntawv cog lus ntawm ob esters lossis ib qho ester thiab carbonyl compound. Cov tshuaj tiv thaiv no tshwm sim thaum muaj lub hauv paus muaj zog uas ua rau muaj beta-keto ester lossis beta-diketone. Cov tshuaj tiv thaiv tau muaj npe tom qab tus kws tshawb fawb Rainer Ludwig Claisen. Cov qauv tshuaj tiv thaiv dav dav yog raws li hauv qab no:

Qhov txawv ntawm Claisen thiab Dieckmann Condensation
Qhov txawv ntawm Claisen thiab Dieckmann Condensation

Daim duab 01: Tshuaj Equation rau Claisen Condensation

Muaj qee qhov yuav tsum tau ua rau qhov kev tshwm sim no tshwm sim. Ib qho kev xav tau yog tias yuav tsum muaj tsawg kawg yog ib qho reagent uas yog enolizable. Nyob rau hauv lwm yam lus, tsawg kawg yog ib tug reactant yuav tsum muaj ib tug alpha proton thiab no proton yuav tsum tau undergo deprotonation, tsim cov enolate anion. Muaj qee qhov sib xyaw ua ke ntawm enolizable thiab nonenolizable carbonyl compounds uas tuaj yeem ua rau Claisen condensation cov tshuaj tiv thaiv. Lwm qhov tseem ceeb ntxiv rau qhov yuav tsum tau ua yog tias lub hauv paus muaj zog yuav tsum tsis txhob cuam tshuam nrog Claisen cov tshuaj tiv thaiv los ntawm kev hloov pauv nucleophilic lossis ntxiv nrog carbonyl carbon atoms. Lwm qhov yuav tsum tau muaj yog cov alkoxy proton ntawm ester, uas yuav tsum yog ib pab pawg neeg zoo.

Dieckmann Condensation yog dab tsi?

Dieckmann condensation yog ib hom kev ua lub nplhaib-tsim cov tshuaj tiv thaiv uas cov neeg tua hluav taws ua rau muab beta-keto esters. Nws yog, yog li ntawd, ib qho tshuaj tiv thaiv intramolecular thiab nws tau muaj npe tom qab tus kws tshawb fawb German W alter Dieckmann. Qhov no yog cov tshuaj tiv thaiv intramolecular uas sib npaug rau Claisen condensation, uas yog cov tshuaj tiv thaiv intermolecular. Cov qauv tshuaj tiv thaiv dav dav rau cov tshuaj tiv thaiv no yog raws li hauv qab no:

Qhov txawv tseem ceeb - Claisen vs Dieckmann Condensation
Qhov txawv tseem ceeb - Claisen vs Dieckmann Condensation

Daim duab 02: Dieckmann Condensation Reaction

Thaum xav txog cov tshuaj tiv thaiv ntawm Dieckmann condensation cov tshuaj tiv thaiv, nws cuam tshuam nrog deprotonation ntawm ib qho ester ntawm alpha txoj hauj lwm uas ua rau ib qho enolate ion uas tuaj yeem ua rau 5-exo-trig nucleophilic nres, muab lub voj voog enol. Txawm li cas los xij, protonation ntawm cov khoom no nrog Bronsted-Lowry acid rov tsim cov beta-keto ester. Nyob rau hauv cov tshuaj tiv thaiv no, tsib thiab rau-tus tswv cuab rings tsim vim lub steric stability. Piv txwv li, 1, 6-diesters tuaj yeem tsim tsib-tus tswv cuab beta-keto ester rings thaum 1, 7-diesters tsim rau-tus tswv cuab beta-keto ester rings.

Qhov txawv ntawm Claisen thiab Dieckmann Condensation yog dab tsi?

Claisen condensation yog ib hom kev sib txuas cov tshuaj tiv thaiv uas muaj cov pa roj carbon-carbon daim ntawv cog lus ntawm ob esters lossis ib qho ester thiab carbonyl compound. Dieckmann condensation yog ib hom nplhaib-forming cov tshuaj tiv thaiv nyob rau hauv uas diesters hnov qab muab beta-keto esters. Yog li ntawd, qhov sib txawv tseem ceeb ntawm Claisen thiab Dieckmann condensation yog tias Claisen condensation cov tshuaj tiv thaiv yog ib hom kev sib txuas cov tshuaj tiv thaiv, whereas Dieckmann condensation cov tshuaj tiv thaiv yog ib hom kev tsim lub nplhaib.

Hauv qab infographic teev cov ntsiab lus ntawm qhov sib txawv ntawm Claisen thiab Dieckmann condensation.

Qhov sib txawv ntawm Claisen thiab Dieckmann Condensation nyob rau hauv daim ntawv Tabular
Qhov sib txawv ntawm Claisen thiab Dieckmann Condensation nyob rau hauv daim ntawv Tabular

Summary – Claisen vs Dieckmann Condensation

Claisen condensation thiab Dieckmann condensation yog hom kev sib xyaw ua ke uas dej / cawv raug tsim los ntawm cov tshuaj tiv thaiv. Qhov sib txawv tseem ceeb ntawm Claisen thiab Dieckmann condensation yog tias Claisen condensation cov tshuaj tiv thaiv yog ib hom kev sib txuas cov tshuaj tiv thaiv whereas Dieckmann condensation cov tshuaj tiv thaiv yog ib hom kev tsim lub nplhaib.

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