Pirol Ve Alkil Pirollerde Asit Katalizli PROTON Değişiminin Teorik Olarak İncelenmesi

Yıl 2010, Cilt: 23 Sayı: 2, 115 - 136, 31.12.2010

Cemil Öğretir Ülkü Gülşah Koyuncu Taner Arslan

Öz

Bazı pirol ve alkil pirol türevlerinde C-H hidrojen-döteryum değişimi semi-empirik metodlar kullanılarak sıvı ve gaz fazında incelenmiştir. Reaksiyon hız sabitleri(k), Arrhenius eşitliği kullanılarak hesaplanmıştır. Hesaplanan hız sabiti değerleri, deneysel hız sabiti değerleri ile karşılaştırılmıştır. Böylece, α, β pozisyonlarıı aktiviteleri ve alkil grubu etkisi incelenmişir. Alkil grubunun, komş konumlarıı, proton değşmini kolaylaşıdığısaptanmışı. Teorik ve deneysel sonuçar arasıda kabul edilebilir bir uyum saptanmışı.

Anahtar Kelimeler

Semi-empirik hesaplamalar, Hidrojen-döteryum değişimi, Asit katalizi, Pirol

Theoretical Studies On Acid Catalysed Proton Exchange Of Pyrrole And Alkyl Pyrroles

Öz

Aqueous and gas phase C-H hydrogen-deuterium exchange of some pyrrole and alkyl pyrrole derivatives were investigated by semi-empirical methods. Rate constants were calculated from Arrhenius equation. The computed rate constants were compared with the experimental ones. In this way, the activity of α and β positions and the effect of alkyl groups were examined. It was found that the alkyl group activates adjacent position of the ring towards proton exchange. An acceptable correlation was detected between experimetal and theoretical results.

Anahtar Kelimeler

Semi-empirical calculations, Hydrogen-deuterium exchange, Acid cataysed, Pyrrole

Kaynakça

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