Stable potassium enolates of N,N-diethylacetamide [alpha-potassio-N,N-diethylacetamide (1)], N,N-diethylpropionamide [alpha-potassio-N,N-diethylpropionamide (2)], and N,N-diethyhsobutyramide [alpha-potassio-N,N-diethylisobutyramide (3)] were prepared by the proton abstraction of the corresponding N,N-diethylamides with diphenylmethylpotassium. (Ph2CHK) or potassium naphthalenide in THF. The relative nucleophilicity of 1-3 was estimated to be in the order of 1 < 3 < 2 from the results of the alkylation reaction with methyl iodide. N,N-diethylacetamide transferred its a-proton to 2 quantitatively in THF at 0 degrees C, whereas no reaction occurred between N,N-diethylisobutyramide and 2; this indicated the relative basicity to be 1 < 2 similar to 3. Anionic polymerizations of N,N-diethylacrylamide (DEA) and methyl methacrylate were quantitatively initiated with 2 in THF at -78 degrees C, whereas the initiation efficiencies of 2 for styrene and 2-vinylpyridine were about 2 and 67%, respectively. The initiation of DEA with 1-3 at -78 or 0 degrees C in THF gave poly (DEA)s having broad molecular weight distributions (MWDs; M-w/M-n = 2) and ill-controlled molecular weights. In contrast, poly(DEA)s of narrow MWDs (M-w/M-n < 1.2) and predicted M-n's were obtained with 2 in the presence of diethylzine (Et2Zn) at -78 degrees C, whereas the initiations with 1/Et2Zn and 3/Et2Zn at -78 degrees C resulted in poor control of the molecular weights. At the higher temperature of 0 degrees C, all the binary initiator systems (1-3/Et2Zn) induced controlled polymerizations of DEA in terms of the conversion, molecular weight, and MWD. The poly(DEA)s produced with 1-3/Et2Zn at 0 degrees C showed mr-rich configurations (mr = 76-89%), as observed for the poly(DEA) generated with Ph2CHK/Et2Zn. (c) 2007 Wiley Periodicals, Inc.