Fenilglioksalin naftol türevleri ile reaksiyonlarının incelenmesi

Abstract

Bu çalışmada bir a-dikarbonil bileşiği olan fenilglioksal ile naftalen türevlerinin asidik ortamda reaksiyonları incelenmiştir. Naftalen türevleri olarak; p-naftol, 6-bromo-2-naftol, 2-naftalintiol, 2, 7-dihidroksi- naftalen bileşikleri kullanılmıştır. Başlangıç bileşiği olan fenilglioksal, asetofenonun SeÛ2 ile oksidasyonuyla hazırlanmıştır. Türev sayısını arttırabilmek amacıyla, asetofenon nitrolanarak, m-nitroasetofenon elde edilmiştir. Elde edilen bu bileşiğin SeÛ2 ile oksidasyonu sonucunda m-nitro- fenilglioksal bileşiği hazırlanmıştır. Daha sonra m-nitro- fehilglioksalin, p-naftol ve 2-naftalintiol bileşikleriyle reaksiyonu gerçekleştirilmiştir. Elde edilen ürünlerin yapıları, TLC, İR, 1H-NMR ve GC- MS analiz yöntemleriyle aydınlatılmaya çalışılmıştır.

One of the starting materials, phenylglyoxal was synthesized from acetophenone by oxidation with selenium dioxide, and then the hydrate form was prepared by boiling with excess water. Its melting point was found 73°C. / \ C-CH + Se00 ». f \ C-C-H -t- Se + H?0 \ / I| 3 2 \ / II II 2 o o o The obtained phenylglyoxal-monohydrate was reacted with 2-naphthol in acidic media. The melting point of product was 289°C. This value was different from the starting compounds that are phenylglyoxal and 2-naphthol. The structure of the product was deduced by ÎR, ^H-NMR, 13C- NMR, GC-MS spectra and TLC analysis. From the spectral data, it can be seen that the product is an oxepin derivative. This was unexpected resul t, because it was a öne step reaction to prepare dibenzoxepin derivatives. ^. naphthyl (D The molecular weight of this product was found 402 by the mass spectrum. The suggested mechanism leading to this product wa3 shown below. vi (IV) %60 C- CH NO. The obtained m-nitrophenylglyoxal was reacted with 2- naphthol. When the IR of the product was compared with the IR spectrum of the compound (I), it was seen that the band at 1700cm-1 was disappeared. This was the surprising result, because two carbonyl groups of phenylglyoxal were utilized in the reaction. The possible structure without carbonyl groups was shown below. (V) To form this material the suggested reaction mechanisr consisted of two steps: alkvlation and acetylation.