A Cost-Effective Way to Produce Gram-Scale 18 O-Labeled Aromatic Aldehydes.

Obtaining 18 O-labeled organic substances is of great research importance and also an extremely challenging work. In this work, depending on the reversed Knoevenagel reaction, 18 O-labeled aromatic aldehydes ( 3a-3x ) are successfully obtained with high total yields (52-72%) and sufficient 18 O abundance (90.90-96.09%).