A novel and practical procedure for the synthesis of small molecules possessing beta-hydroxy or N-tosylamino 1,2,3-triazole motif by azidation of epoxides or N-tosylaziridines with sodium azide followed by "click reaction" using eco-friendly PEG-400 as a reaction medium in the presence of 5 mol % of CuI is described. Enantiomerically pure epoxide and N-tosylaziridines were afforded in high yield with excellent ee values maintaining complete stereospecificity.

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The synthesis of regio- and stereoselective aryl substituted α,β-unsaturated aldehydes and ketones from activated allenes was achieved. This mild and non-metallic oxidation is exclusively driven by benign ambient air and triggered by visible light. The same starting materials under ideal anaerobic conditions led to the 2,3-diphenylselenation adduct with no trace of oxygenated products, demonstrating dissolved oxygen as a chemical switch for two different reaction pathways. The salient feature of this protocol is the single electron transfer (SET) achieved by irradiation of one of two organic molecules thereby avoiding a sensitizer to form a radical ion pair.

A cationic Pd(IV)-catalyzed arylative hydroxylation-Micheal addition of allenyl-tethered cyclohexadienones was developed. This relay reaction could afford highly diastereoselective various functionalized arylative 1,4-dioxane cis-bicyclic structural units with good to high yields. The striking features revealed from these studies is the necessity of Selectfluor and the oxidative hydroxylation originating from water initiated by F−Pd(IV) catalysis. A plausible mechanism was also proposed for this variant observation.