One-Pot Synthesis and X-Ray Structure of New, Stable Tetrahydropyrrolo [1,2-a][1,10]phenanthrolines with Four Diastereoisomeric Centers

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

Keywords:

• Diastereoisomeric centers
• domino-Knoevenagel condensation
• 1,10-phenanthrolinium N-ylide
• tetrahydropyrrolo[1,2-a][1,10]phenanthrolines

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∥F_o| − |F_c∥/Σ|F_o|, wR2 = [Σ[w(F_o ² − F_c ²)²] / Σ[w(F_o ²)²].