An efficient synthesis of N-(trideuteromethyl)morpholine-N-oxide monohydrat
e (3) is described. The procedure applies the tocopheryl protecting group,
and makes use of sodium percarbonate as the oxidant and water donor, thus a
voiding both the troublesome direct alkylation of morpholine and the unsuit
able oxidation by aqueous hydrogen peroxide. Overall yields of purified mat
erial range above 90%.