Highly Efficient Organic Reactions “on Water”, “in Water”, and Both

Wet, wet, wet : Hydrophobic aldehydes are cleanly oxidized upon stirring with water in air. Addition of hydrophobic isocyanides to aqueous suspensions of such aldehydes results in the formation of Passerini reaction products, with the aldehyde being the source of both carbonyl and ester functions. Partially water‐soluble reagents reacted slower than water‐insoluble ones. Isotope labeling studies show that water participates in these “on water” reactions.