Two hitherto unknown planar aromatic  fused heterocyclic macrocycles (18.104.22.168.1.0), with NIR absorption in free-base form and protonation-induced enhanced NIR emission, have been synthesized from easy to make precursors. The induced correspondence of fusion on the macrocyclic structure, electronic absorption, and emission spectra have been highlighted.
Bibliographical noteFunding Information:
The work at IACS, Kolkata was supported by DST-SERB (SR/S1/IC-37/2012), CSIR (02(0120)/13/EMR-II), New Delhi, India and DST-SERB Ramanujan Fellowship (SR/S2/RJN-93/2011), India. A.M. thanks CSIR for senior research fellowship. The work at Yonsei University was supported by the Global Research Laboratory Program (2013K1A1A2A02050183) funded by the Ministry of Science, ICT & Future, Korea. The quantum calculations were performed using the supercomputing resources of the Korea Institute of Science and Technology Information (KISTI). We are indebted to the Single Crystal X-Ray Diffractometer facility in IISER, Pune, India. Our sincere thanks to Dr. R. Natarajan, IICB, Kolkata for final refinement of crystal data.
All Science Journal Classification (ASJC) codes
- Organic Chemistry