Abstract
1,10-Phenanthrolinium N-ylides react with ethyl cyanoacetate and aromatic aldehydes via a domino-Knoevenagel cyclization to produce a new class of tetrahydropyrrolo [1,2-a][1,10] phenanthrolines with four diastereoisomeric centers as stable helical compounds in a simple, mild, and efficient protocol in excellent yields. Explicit structural elucidation of compounds was accomplished by single-crystal x-ray diffraction.
GRAPHICAL ABSTRACT
ACKNOWLEDGMENTS
We gratefully acknowledge financial support from the Research Council of University of Sistan and Balouchestan. Also we warmly thank Claudia Graiff for the x-ray structure determination.
Notes
a R 1 = Σ∥Fo| − |Fc∥/Σ|Fo|, wR2 = [Σ[w(Fo 2 − Fc 2)2] / Σ[w(Fo 2)2].