Reaction of Hydrazonoyl Halides With 5-Arylmethylene-3-Phenyl-2-Thioxothiazolidin-4-One. Synthesis of 4,9-Dithia-1,2,6-Triazaspiro[4,4]nonan-2-en-7-One

Regio- and Chemoselective Synthesis of 4,6-Dithia-1,2,9-triazaspiro[4.4]non-2-en-8-ones through an Ultrasound-Promoted One-Pot Sequential Pseudo-Five-Component Reaction

“…Previous reports have shown that this reaction is influenced by the interaction of the HOMO of the nitrilimine and the LUMO of the dipolarophile (double bond) as well as the relative magnitude of the orbital coefficients in these frontier orbitals leading to the regioselectivity of the reaction. 43,44 Moreover, nitrilimines tend to react with the most polar double bonds of a compound. In intermediate 5a (Scheme 3), the polarity of the double bonds increases in the following order: C=C, C=O, and C=S.…”

“…In intermediate 5a (Scheme 3), the polarity of the double bonds increases in the following order: C=C, C=O, and C=S. 15,[43][44][45] Accordingly, Scheme 3 shows the proposed mechanism for the formation of 7a. Initially, the reaction between benzylamine (1a), CS 2 , and ethyl bromoacetate (2) results in the formation of intermediate II.…”

A Convenient Regioselective Synthesis of Novel 1,4‐Phenylenemethylene‐6,6′‐bis‐([1,2,4‐triazolo]‐[4,3‐b][1,2,4]‐triazin‐7(1H)‐ones)

“…Also, they showed a broad spectrum against leukemic cell lines and a wide range of cancer cells . In continuation to our previous research directed toward reaction of hydrazonoyl halides with various heterocyclic thione to synthesize triazolo[1,2,4]triazine , triazolo[4,3‐ a ]quinazoline , triazolopetridine , pyridine[2,3‐ d ]pyrimidine , triazolo[4,3‐ a ]pyrimidine , and spiroheterocycles , it was thought interesting to study reactions of such halides with the new 6,6′‐(1,4‐phenylenedimethylene)bis‐(3‐thioxo‐1,2,4‐triazin‐5(1 H )‐ones) 4 ( 5 ) (Scheme ). Our objective after such a study is on one hand to shed some light on the regioselectivity in such reactions and on the other hand to explore the biological activity of the products isolated from such reactions.…”

Synthesis of New Pyrazoles via Cycloaddition Reactions of Nitrilimines with 2‐Cyclopentenone Derivatives

“…Nitrilimines are considered reactive reagents in organic synthesis and are useful for the construction of a five‐membered heterocyclic system through the 1,3‐dipolar cycloaddition reaction with alkenes , alkynes , azomethines , heterocyclic residues , or α , β ‐unsaturated carbonyl compounds (conjugated ketone‐exocyclic arylmethylidenes) .…”