Qhov sib txawv tseem ceeb ntawm Clemmensen thiab Wolff Kishner txo yog tias Clemmensen txo qhov cuam tshuam nrog kev hloov pauv ntawm ketone lossis aldehydes rau hauv alkanes qhov txo qis Wolff Kishner suav nrog kev hloov pauv ntawm pawg carbonyl rau hauv pawg methylene.
Ob txoj haujlwm no ua cov kev hloov pauv no los ntawm kev txo cov pab pawg ua haujlwm. Yog li ntawd, cov txheej txheem no yuav tsum muaj cov tshuaj tiv thaiv tshwj xeeb thiab cov catalysts rau kev vam meej ntawm cov tshuaj tiv thaiv. Txij li cov reactants rau txhua tus txheej txheem yog cov organic molecules, peb siv cov txheej txheem no hauv cov organic synthesis cov tshuaj tiv thaiv.
Clemmensen txo yog dab tsi?
Clemmensen txo yog ib qho tshuaj lom neeg cov tshuaj tiv thaiv uas peb hloov cov ketone los yog aldehydes rau hauv alkane. Peb yuav tsum siv lub catalyst rau cov tshuaj tiv thaiv no; Nws yog amalgamated zinc (mercury alloyed nrog zinc) nrog hydrochloric acid. Yog li ntawd, mercury alloyed nrog zinc tsis koom nrog cov tshuaj tiv thaiv. Nws tsuas yog muab lub ntsej muag huv si, ua haujlwm rau cov tshuaj tiv thaiv. Lub npe ntawm cov txheej txheem muab los tom qab tus kws tshawb fawb Danish Erik Christian Clemmensen.
Daim duab 01: Ib qho Kev Sib Txuas Sib Txuas rau Clemmensen Txo
txheej txheem no muaj txiaj ntsig zoo hauv kev txo qis ntawm aryl-alkyl ketones. Ntxiv mus, cov zinc hlau txo tau zoo dua nrog aliphatic lossis cyclic ketones. Qhov tseem ceeb tshaj plaws, lub substrate ntawm cov tshuaj tiv thaiv no yuav tsum tsis muaj kev cuam tshuam rau cov acidic cov tshuaj tiv thaiv.
Wolff Kishner txo yog dab tsi?
Wolff Kishner txo yog cov tshuaj lom neeg cov tshuaj tiv thaiv uas peb siv los hloov cov pa roj carbonyl ua haujlwm rau hauv pawg methylene. Cov tshuaj tiv thaiv no tau txais nws lub npe tom qab ob tus kws tshawb fawb Nikolai Kirschner thiab Ludwig Wolff. Cov kev siv loj ntawm cov tshuaj tiv thaiv no yog nyob rau hauv kev sib txuas ntawm scopadulcic acid B, aspidospermine thiab dysidiolide.
Daim duab 02: Wolff Kishner txo qhov tshwm sim
Tsis zoo li Clemmensen txo qis, qhov tshuaj tiv thaiv no yuav tsum muaj cov xwm txheej yooj yim. Yog li ntawd, nyob rau hauv cov txheej txheem tshuaj tiv thaiv, thawj kauj ruam yog tsim hydrazone ntawm condensation ntawm hydrazine nrog rau ketone los yog aldehyde substrate. Tom qab ntawd raws li theem ob, peb yuav tsum deprotonate hydrazone siv alkoxide puag. Tom qab ntawd, los ntawm cov kauj ruam uas lub diimide anion tsim. Tom qab ntawd cov anion tawg tso tawm N2 roj, thiab nws ua rau tsim cov alkylation. Thaum kawg, peb tuaj yeem protonate no alkylation kom tau cov khoom xav tau.
Qhov txawv ntawm Clemmensen thiab Wolff Kishner txo yog dab tsi?
Clemmensen thiab Wolff Kishner txo yog qhov tseem ceeb heev hauv cov organic synthesis ntawm cov tshuaj sib txawv. Txawm li cas los xij, qhov sib txawv tseem ceeb ntawm Clemmensen thiab Wolff Kishner txo yog tias Clemmensen txo qis cuam tshuam nrog kev hloov pauv ntawm ketone lossis aldehydes rau hauv alkanes thaum Wolff Kishner txo qis cuam tshuam nrog kev hloov pauv ntawm pawg carbonyl rau hauv pawg methylene. Ntxiv mus, peb siv cov catalyst hauv Clemmensen txo cov tshuaj tiv thaiv; nws yog amalgamated zinc. Tab sis peb tsis siv lub catalyst rau Wolff Kishner txo cov tshuaj tiv thaiv. Lwm qhov sib txawv ntawm Clemmensen thiab Wolff Kishner txo yog tias Clemmensen txo qis siv cov kua qaub zoo, yog li tsis tsim nyog rau cov kua qaub-rhiab substrates. Whereas, Wolff Kishner txo qis siv cov kev mob yooj yim heev; yog li, tsis haum rau lub hauv paus rhiab substrates.
Cov hauv qab no infographic tabulates qhov sib txawv ntawm Clemmensen thiab Wolff Kishner txo kom meej ntxiv.
Summary – Clemmensen vs Wolff Kishner Txo
Muaj ntau yam tshuaj lom neeg sib txawv uas peb siv hauv cov tshuaj lom neeg rau kev sib txuas ntawm cov ntsiab lus tseem ceeb. Li no, Clemmensen thiab Wolff Kishner txo yog ob qho kev tshwm sim. Qhov sib txawv tseem ceeb ntawm Clemmensen thiab Wolff Kishner txo yog tias Clemmensen txo qhov cuam tshuam nrog kev hloov pauv ntawm ketone lossis aldehydes rau hauv alkanes qhov txo qis Wolff Kishner suav nrog kev hloov pauv ntawm pawg carbonyl rau hauv pawg methylene.
