Solar light photo-catalyzed condensation of aldones with 4-phenylthiosemicarbazide, a green chemistry approach

A significant photo-activating effect was evidenced upon investigating the condensation of aldehydes and ketones with 4-phenylthiosemicarbazide in the absence of any type of catalyst (either acido-basic or nucleophilic catalysis). Actual yields were not found superior to those obtained using nucleophilic catalysts; however, the reaction can be run at room temperature with the absence of an additional solvent. A positive hydrophobic effect was also noted. Furthermore, it was found that, the described photo-chemical method did not require an expensive and energy-consuming photo-chemical equipment since the whole process was carried out using natural solar light in regular laboratory glass ware.