Abstract
A novel and simple method for the N-alkylation of amines with different ethers as alkylating reagents has been developed, using cheap γ-Al2O3 as the catalyst at atmospheric pressure in the temperature range of 260–320°C. For example, the reaction of equimolar amounts of morpholine and diethyl ether gave N-ethylmorpholine quantitatively. The present catalytic system is applicable to the N-alkylation of both primary and secondary amines. Since only water is generated as byproduct, the protocol proved to be eco-friendly and atom-economic.
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