Synthesis of 2,5‐disubstituted oxazoles from aldehydes and N‐(tosylmethyl)imino synthons. Application to the synthesis of pimprinine analogues

A series of N‐(tosylmethyl)imino compounds [TosCH2NC(L)A] has been applied to a new base‐induced, one‐operational synthesis of 2,5‐disubstituted oxazoles from aromatic aldehydes. For substituent A of the imino compounds, which becomes the 2‐substituent in the oxazoles, has been chosen methoxy, methyl and phenyl. The new method has been used also to synthesize seven pimprinine analogues, i.e., 5‐(‐3)indolyl)oxazoles.