The intramolecular alkyne-azide Huisgen [3+2] cycloaddition reaction as a 'click-chemistry' reaction without a metal catalyst has been studied under aerobic conditions. The synthesis of various pyrrolidine-triazole hybrid compounds has also been achieved by using this intramolecular cycloaddition reaction in water with complete 1,5-regioselectivity. (C) 2012 Elsevier Ltd. All rights reserved.