An experimental and theoretical reinvestigation of the Michael addition of primary and secondary amines to dimethyl acetylenedicarboxylate

作者：Gurjar Asha; Poonia Priyadarshni; Sinha Pragya; Bansal Raj K^*

来源：Tetrahedron Letters, 2014, 55(15): 2504-2507.

DOI：10.1016/j.tetlet.2014.03.013

• Michael addition
• DMAD
• DFT calculations
• 1,3-Prototropic shift
• alpha-Imino ester

Theoretical calculations of the Michael addition of diethylamine, pyrrolidine, and benzylamine to DMAD at the DFT (B3LYP/6-31+G*) level indicate that the reaction follows a stepwise mechanism via a zwitter-ionic intermediate. The reactions have low activation barriers, 13-15 kcal mol(-1) and are exothermic, Delta H degrees = -29 to -44 kcal moll. The detailed investigation of the reaction of benzylamine with DMAD reveals participation of the reactant-, transition structure-, and the product-complexes and that the 1,3-prototropic shift occurs through the benzylamine molecule. It also predicts formation of dimethyl 2-(N-benzylimino)butane-1,4-dicarboxylate as one of the products, which has been duly isolated and characterized experimentally.

• 出版日期2014-4-9