In our projects we need a wide range of maleimides derivatives, particularly with linkers having alkane chain 4a, ethers, 4b, 4c, Polyethylene Glycols (PEG), 4d and alkyne group 4e and ethylene glycol-OH groups compounds 4f and 4g. To achieve these compounds, we employed most used method such as maleamic acid dehydration in presence AcONa 11 (method-A) and N-carbonyl maleimid N-(Methoxycarbonyl) maleimide (method) .