Photoenolization via excited state double proton transfer induces "turn on" fluorescence in diformyl diaryl dipyrromethane.

A light triggered enolization in diformyl diaryl dipyrromethane by excited state dual proton transfer (ESDPT) induces "turn on" fluorescence. The role of diaryl and diformyl groups in the enolization process was confirmed by photophysical and theoretical studies.

4,4,9,9-Tetraphenyl pyrroloindolizine: a structural analogue of calix[2]pyrrole.

Synthesis, spectral and structural characterization of a pyrroloindolizine derivative having structural similarity with calix[2]pyrrole is described. Here, two pyrrole rings are connected with two meso-carbon atoms having an N,α-linkage and an α,ß-linkage to afford the smallest analogue in the calixpyrrole family. Detailed NMR spectroscopic studies along with single crystal X-ray analysis confirm the assigned structure of the molecule.