1113-68-4Relevant articles and documents
Acyl iodides in organic synthesis. Reaction of acyl iodides with N,N-dimethyl carboxylic acid amides
Voronkov,Tsyrendorzhieva,Rakhlin
, p. 1476 - 1478 (2010)
Acyl iodides RCOI (R = Me, Ph) reacted with N,N-dimethylformamide and N,N-dimethylacetamide Me2NC(=O)R' (R' = H, Me) along two concurrent pathways involving transacylation and cleavage of the Me-N bond. The first pathway leads to the formation of acyl group exchange products, and the second, to the corresponding imides R'CON(Me)COR.
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Abel,Armitage
, p. 5975,5977 (1964)
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Gas-phase Pyrolytic Reactions. Part 5. Rate Data for Pyrolysis of N-t-Butyl- and N-Acetyl-benzamide, N-Acetyl-N-methylacetamide, and N-Ethyl- and N-Prop-2-yl-thioacetamide
Al-Awadi, Nouria A.
, p. 2187 - 2189 (2007/10/02)
The rates of gas-phase elimination of N-t-butylbenzamide 1, N-acetylbenzamide 2, and N-acetyl-N-methylacetamide have been measured in the ranges 674-734, 580-620 and 696-765 K, respectively.The compounds undergo unimolecular first order elimination reactions for which log A = 11.1, 13.7 and 10.5 s-1 and Ea = 172.6, 171.7 and 167 kJ mol-1, respectively.At 600 K, the following reactivity ratios are observed: 1 : N-t-butylacetamide 3, 260; t-butyl benzoate 4 : t-butylacetate 5, 2.3; N-acetylacetamide 6 : N-acetyl-N-methylacetamide, 290; and 2 : 6, 3.6.These relative rate factors show that the phenyl group increases the rate of thermolysis due to its electron-withdrawing ability 250 times more for simple amides than for esters and diamides.These relative rate differences are highly affected by the nature of the Cα-X bond.The pronounced effect of the phenyl group on simple amides could be explained in terms of the low polarity of the Cα-NH bond relative to the more polar Cα-O bond in esters.On the other hand the pronounced deactivation effect of the methyl group in N-acetyl-N-methylacetamide is highly reflected in the reactivity ratio of 290 between 6 and N-acetyl-N-methylacetamide which could be explained in terms of the greater bond order of the Cα-X bond in the latter than in the former.Furthermore, the small reactivity ratio in the diamides 2 and 6 is consistent with the fact that resonance between the lone-pair of electrons on X and the α-carbonyl group increases the Cα-X bond order, thus rendering the Cα-X bond breakage more difficult.We have also measured the rates of thermolysis of N-ethylthioacetamide and N-prop-2-ylthioacetamide.The relative primary : secondary : tertiary rates at 600 K of 1 : 1.3 : 1.5 for the thioamides suggests that the transition state for this class of compound is much less polar than that for the thioacetates.
