| Abstract
| - In the presence of onium salts, at 140−170 °C, methyl alkylcarbonates [1a−c, ROCO2Me, R = MeO(CH2)2[O(CH2)2]n; n= 2−0, respectively] react with primary aromatic amines(XC6H4NH2, X= p-OMe, p-Me, H, p-Cl, p-CO2Me, o-Et, and2,3-Me2C6H3NH2) to yield the corresponding N,N-dimethylderivatives (ArNMe2) with high selectivity (up to 96%) and goodisolated yields (78−95%). Phosphonium salts (e.g., Ph3PEtI andn-Bu4PBr) are particularly efficient catalysts. Overall, a solvent-free reaction is coupled with safe methylating agents (1a−c)made from nontoxic dimethyl carbonate.
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