- Turkish Journal of Chemistry
- Vol: 38 Issue: 1
- On the peculiar reactivity of a C,N-annelated isoindole core
On the peculiar reactivity of a C,N-annelated isoindole core
Authors : Iaroslav Baglai, Valérie Maraval, Zoia Vsevolodivna Voitenko
Pages : 121-126
Doi:10.3906/kim-1306-58
View : 7 | Download : 4
Publication Date : 9999-12-31
Article Type : Makaleler
Abstract :C-, N-, and/or O-methylation products were generated from 11H-isoindolo[2,1-a]quinazoline-5-one upon treatment with NaH followed by iodomethane under air, and possible recrystallization from methanol. Two products were fully characterized by NMR and X-ray diffraction analysis. In accordance with the HSAB principle, this soft methylating agent (MeI) leads mainly to the C,C-dimethylated product 11,11-dimethyl-11H-isoindolo[2,1-a]quinazoline-5-one, which was previously not observed, beside the N-methylated product, in a procedure using methyl tosylate as a hard methylating agent of the same substrate in the initial absence of a base. A mechanism is finally proposed for the formation of methyl 2-(3-methyl-4-oxo-3,4-dihydroquinazolin-2-yl)benzoate as an oxidation side product.Keywords : Isoindoles, methylation processes, oxidative ring opening, quinazolines