Abstract Arylmethylisoxazol-5-ones (3) were prepared by a new mild reductive procedure using tertiary amines containing a flexible N− CH− CH grouping. A concurrent process competed with the reduction, yielding fair quantities of chain-elongation products (4). The X- ray structures of two selected arylmethyl derivatives are reported and are shown to have the expected different tautomeric arrangements. The unusual features of the NH-tautomer (3e) ...