title: Synthesis of Pyrrole-Fused C,N-Cyclic Azomethine Imines and Pyrazolopyrrolopyrazines: Analysis of Their Aromaticity Using Nucleus-Independent Chemical Shifts Values.
abstract: The AgOTf-catalyzed reaction of C-2 substituted pyrrole hydrazones having an N-propargyl group was studied. The selective 6-endo-dig mode of cyclization was observed, giving rise to the formation of pyrrole-fused C,N-cyclic azomethine imine derivatives. The reaction of one azomethine imine derivative with various dipolarophiles resulted in the formation of cycloadducts having a pyrazolopyrrolopyrazine skeleton. The aromaticity of C,N-cyclic azomethine imines as well as that of pyrazolopyrrolopyrazines was determined by calculating of nucleus-independent chemical shifts values.
authors.affiliation: Department of Chemistry, Middle East Technical University , 06800 Ankara, Turkey.
authors.forename: Merve Sinem
authors.initials: MS
authors.lastname: Özer
authors.affiliation: Department of Chemistry, Middle East Technical University , 06800 Ankara, Turkey.|Faculty of Pharmacy, Yüzüncü Yil University , 65100 Van, Turkey.
authors.forename: Nurettin
authors.initials: N
authors.lastname: Menges
authors.affiliation: Department of Chemistry, Middle East Technical University , 06800 Ankara, Turkey.|Department of Chemistry, Giresun University , 28100 Giresun, Turkey.
authors.forename: Selbi
authors.initials: S
authors.lastname: Keskin
authors.affiliation: Department of Chemistry, Atatürk University , 25240 Erzurum, Turkey.
authors.forename: Ertan
authors.initials: E
authors.lastname: Şahin
authors.affiliation: Department of Chemistry, Middle East Technical University , 06800 Ankara, Turkey.
authors.forename: Metin
authors.initials: M
authors.lastname: Balci