Alkalinity thiab ntsev tsim ntawm Pyridine

Unshared electron khub ntawm pyridine nitrogen atoms txais protons thiab ua alkaline. Lub conjugate acid ntawm pyridine (pyridine tom qab tau txais ib qho proton ntawm N atom) muaj pKa ntawm 5.25, uas yog acidic ntau dua ammonia (pKa9.24) thiab fatty amines (pKa 10-11) (qhov me dua pKa, qhov ntau acidic nws). Yog vim li cas yog vim li cas yog tias tsis sib koom electron khub ntawm nitrogen atom nyob rau hauv pyridine yog nyob rau hauv sp2 hybrid orbital, thiab nws s orbital tivthaiv yog ntau tshaj sp3 hybrid orbital, nyob ze rau lub nucleus, lub electron muaj zog khi los ntawm lub nucleus, thiab cov nyiam mus. muab electrons me me, yog li nws nyuaj rau kev sib xyaw nrog cov proton thiab cov alkalinity tsis muaj zog. Txawm li cas los xij, pyridine yog me ntsis yooj yim dua li cov tshuaj tsw qab amines (xws li aniline, pKa 4.6).
Pyridine thiab cov kua qaub muaj zog tuaj yeem tsim cov ntsev ruaj khov, thiab qee cov ntsev crystalline tuaj yeem siv rau hauv kev sib cais, txheeb xyuas thiab kho kom zoo. Lub alkalinity ntawm pyridine yog siv los ua catalyst deacidifier hauv ntau cov tshuaj tiv thaiv. Vim nws zoo solubility nyob rau hauv dej thiab organic solvents, lub catalysis ntawm pyridine yog feem ntau siv tsis tau rau qee cov hauv paus inorganic.
Pyridine tuaj yeem tsim cov ntsev tsis yog nrog cov kua qaub uas muaj zog, tab sis kuj nrog Lewis acids.
Tsis tas li ntawd, pyridine kuj muaj qee yam khoom ntawm tertiary amines, thiab tuaj yeem hnov ​​​​mob nrog halogenated hydrocarbons los ua quaternary ammonium ntsev, thiab tuaj yeem ua rau cov acyl halides los ua cov ntsev.