Microwave-assisted and iodine mediated synthesis of 5-n-alkyl-cycloalkane[d]-pyrazolo[3,4-b]pyridines from 5-aminopyrazoles and cyclic ketones

5-n-Alkylcycloalkane[d]pyrazolo[3,4-b]pyridines were prepared by a microwave-assisted cyclocondensation reaction between 5-aminopyrazoles and cyclic ketones under solvent-free conditions and catalyzed by iodine. This procedure provides a simple one-step and environmentally friendly methodology with good yields for the synthesis of these compounds.