Synthetic method of asymmetry polyarylamino\|benzaldehydes by the selective formylation of polyarylamines in Vilsmeier\|Haack reaction was studied. Five polyarylamino\|benzaldehydes, \{4\|\%N\|\%methylphenylamino\}\|benzaldehyde, 4\|\%N\|\%（\%n\%\|butyl）\|phenylamino\|benzaldehyde, 4\|diphenylamino\|benzaldehyde, 4\|\%N\|\%phenyl\|diphenylamino\|benzaldehyde, 4\|\%N\|\%phenyl\|（4′\|diphenylamino）diphenylamino\|benzaldehyde were synthesized by the selective formylation of the polyarylamines with POCl\-3 and DMF in the yields of 67%\92%. The structures of these aldehydes were characterized by MS, \{\}\+1H NMR, IR. The studied results showed that the yields and selectivity of asymmetry polyarylamino\|benzaldehydes were found to relate with the reaction time, structures of polyarylamines and the molar ratio of the reactants.
