Qhov sib txawv tseem ceeb ntawm carbene thiab carbanion yog cov carbene muaj cov pa roj carbon divalent, whereas carbanion muaj trivalent carbon atom.
Carbene thiab carbanion yog cov organic molecules uas muaj carbon thiab hydrogen lossis lwm yam atoms. Ob hom organic tebchaw no txawv ntawm ib leeg nyob rau hauv lawv cov duab, geometry, valency, oxidation xeev, nqi, thiab lwm yam. Yog li, tsab xov xwm no hais txog qhov sib txawv ntawm carbene thiab carbanion ntawm cov yam.
YCarbene yog dab tsi?
A carbene yog ib qho organic molecule uas muaj cov pa roj carbon nruab nrab nrog lub valence ntawm ob. Hauv lwm lo lus, cov pa roj carbon atom hauv cov carbene compound muaj ob qho tsis sib koom valence electrons. Cov qauv tshuaj dav dav rau hom tshuaj no yog R-(C:)-R' lossis R=C: qhov twg R thiab R' sawv cev rau cov khoom siv lossis hydrogen atoms. Cov qauv dav dav ntawm qhov sib xyaw no yog raws li hauv qab no:
Daim duab 01: Cov Qauv Tshuaj ntawm Carbene
Ntxiv mus, muaj ob chav kawm ntawm carbenes li singlet carbene thiab triplet carbene. Lub singlet carbene tebchaw yog spin-paired compounds. Cov molecules no txais yuav ib qho sp2 hybrid qauv. Triplet carbene tebchaw muaj unpaired electrons. Feem ntau cov carbene tebchaw muaj ib tug triplet qauv nyob rau hauv lawv lub hauv av, tshwj tsis yog rau cov carbene tebchaw uas muaj nitrogen, oxygen, los yog sulfur atoms.
Peb tuaj yeem hu rau carbene compound ib lub singlet lossis triplet qauv nyob ntawm cov khoom siv hluav taws xob ntawm cov molecules. Piv txwv li, triplet carbene tebchaw yog paramagnetic, thiab peb tuaj yeem soj ntsuam cov qauv no los ntawm electron spin resonance spectroscopy yog tias peb tuaj yeem ua kom cov molecules nyob ntev txaus rau kev tshuaj xyuas. Tsis tas li ntawd, qhov spin ntawm singlet carbene molecules yog xoom thaum lub spin ntawm triplet carbene molecules yog ib qho. Ntxiv rau cov no, singlet carbene molecules yog ruaj khov nyob rau hauv ib qho nruab nrab aqueous, whereas triplet carbene molecules yog ruaj khov nyob rau hauv ib tug gaseous xeev.
Carbanion yog dab tsi?
A carbanion yog ib qho anion uas muaj cov pa roj carbon trivalent thiab cov nqi tsis zoo ntawm cov ion. Lub trivalent carbon atom yog ib qho ion uas muaj cov pa roj carbon atom uas tau tsim peb covalent bonds. Txhawm rau muab lub npe sib xyaw ua cov carbanion, nws yuav tsum muaj tus nqi tsis zoo nyob rau hauv tsawg kawg ib tus qauv resonance.
Daim duab 02: Resonance Structures of Carbanions
Ntxiv mus, ib qho carbanion tsis muaj pi-electron delocalization thiab cov molecules xav tias yog trigonal pyramidal, khoov, lossis linear geometry thaum carbanion muaj peb, ob, lossis ib qho kev hloov pauv, feem. Qhov tseem ceeb tshaj, ib qho carbanion yog lub hauv paus conjugate ntawm carbon acid.
Feem ntau, carbanions yog nucleophilic thiab yooj yim. Lub nucleophilicity thiab lub hauv paus ntawm cov tebchaw no tuaj yeem txiav txim siab los ntawm hom kev hloov pauv ntawm cov pa roj carbon atom. Tsis tas li ntawd, muaj peev xwm muaj chiral carbanions ib yam nkaus.
Tsis tas li ntawd, cov hluav taws xob ceev ntawm cov pa roj carbon atom tsis zoo hauv cov carbanion ua rau cov ion tuaj yeem ua rau cov electrophiles muaj zog sib txawv xws li carbonyl pawg, halogenated reagents, thiab lwm yam.
Qhov txawv ntawm Carbene thiab Carbanion yog dab tsi?
Carbene thiab carbanion yog cov organic molecules uas muaj carbon thiab hydrogen lossis lwm yam atoms. Qhov sib txawv tseem ceeb ntawm carbene thiab carbanion yog tias carbene muaj cov pa roj carbon divalent, whereas carbanion muaj trivalent carbon atom. Yog li ntawd, carbene tebchaw muaj carbon atoms muaj ob covalent tshuaj bonds thaum carbanion tebchaw muaj peb covalent daim ntawv cog lus rau cov pa roj carbon atom thiab ib tug formal negative charges thiab.
Hauv qab infographic qhia txog qhov sib txawv ntawm carbene thiab carbanion.
Summary – Carbene vs Carbanion
Carbene thiab carbanion yog cov organic molecules uas muaj carbon thiab hydrogen lossis lwm yam atoms. Qhov sib txawv tseem ceeb ntawm carbene thiab carbanion yog carbene muaj cov pa roj carbon divalent, whereas carbanion muaj trivalent carbon atom.
