Abstract
NaHCO3 has been found to be an efficient base catalyst for the synthesis of pyrano[2,3-a]carbazoles from 1-hydroxycarbazoles by multicomponent reaction using solvent-free grinding methods. In this case, the products have been found in good yields, without formation of any side product.
GRAPHICAL ABSTRACT
ACKNOWLEDGMENTS
We acknowledge URF, Bharathiar University, for the award of a research fellowship. Our sincere thanks go to SAIF, Indian Institute of Technology Madras, Chennai, and the director, ISO Quality Assurance Cell, Indian Institute of Chemical Technology, Hyderabad, for providing access to their NMR and mass spectral facilities. The x-ray diffractometer was funded by NSF Grant 0087210, Ohio Board of Regents Grant CAP-491, and Youngstown State University.