Synthesis of 1,2‐Dicyano‐3‐arylcycl[3.2.2]azines – First 1,2‐Dicarbonitriles Based on Cyclazine Heterocycle

Abstract

The first 1,2‐dicarbonitriles have been prepared for cyclazine systems. In particular, a synthetic procedure to 1,2‐dicyano‐3‐arylcycl[3.2.2]azines has been developed. Unexpected chlorination of 3‐arylcycl[3.2.2]azine‐1,2‐dicarboxylic acid derivatives by thionyl chloride at 4‐position was found, which according to theoretical considerations can proceed by the electrophilic (SEAr) mechanism. The compounds are blue fluorophores in 450–480 nm region with quantum yields in toluene of ca. 30 % for non‐chlorinated derivatives, which decrease to 3–4 % for chlorinated ones.

Acetic Acid‐Catalyzed 1,6‐Addition of Indolizine to para‐Quinone Methides

“…All para ‐quinone methides and indolizine derivatives synthesized using literature procedures [55–57] …”

“…All para-quinone methides and indolizine derivatives synthesized using literature procedures. [55][56][57] General Procedure for the Synthesis of C3-Functionalization of Indolizines: To a solution of indolizine (0.5 mmol) in toluene/AcOH (4 : 1; 3 mL), p-QM (0.5 mmol) was added and the mixture was stirred at room temperature for 12 h. After the reaction was complete (monitored by TLC), the reaction mixture was then diluted with EtOAc and water and extracted with EtOAc. The organic layers were washed with brine, dried over Na 2 SO 4 and evaporated under reduced pressure.…”