65112-55-2Relevant academic research and scientific papers
INTERMOLECULAR IMIDOYLATION REACTION OF THE CARBOXAMIDE GROUP
Mazurkiewicz, Roman
, p. 439 - 450 (2007/10/02)
Reactions of N-monosubstituted benzamides with Ph3PBr2 and Et3N in refluxing CH2Cl2 for 0.5 - 5 hours give good yields of N,N'-disubstituted-N-acylamidines.The latter compounds may be regarded as intermolecular N-imidoylation products of the amide group.Under the same reaction conditions, N-monosubstituted amides containing C-H bonds adjacent to the carbonyl function and N-monosubstituted formamides are dehydrated to ketenimines and isonitriles, respectively.Treatment of N-methyl-benzamide with Ph3PBr2 and Et3N leads to the formation of an intermediate whose ir spectrum is consistent with the N,N,N-triethyl-N'-methylbenzamidinium salt structure.A substance with identical spectroscopic characteristics was obtained on treatment of N-methyl-α-bromobenzylideneammonium bromide with Et3N.Products of the reaction of 5- and 6-membered lactams with Ph3PBr2 and Et3N are inactive as imidoylating agents; consequently, these lactams do not undergo self-condensation to N-imidoylation products, but they can participate in the imidoylation reactions as nucleophiles subjected to imidoylation.In contrast to the 5- and 6-membered lactams, ε-caprolactam undergoes self-condensation to the expected N-imidoylation product.Possible mechanistic pathways for the imidoylation reaction of the amide group have been suggested.
Convenient Preparations of 3,5-Disubstituted 1,2,4-Thiadiazoles by Oxidative Dimerization of Thioamides
Takikawa, Yuji,Shimada, Kazuaki,Sato, Katsuyuki,Sato, Shinichi,Takizawa, Saburo
, p. 995 - 999 (2007/10/02)
3,5-Disubstituted 1,2,4-thiadiazoles 2 were prepared by reaction of thioamides 1 with DMSO in the presence of such an electrophilic reagent as 1-methyl-2-chloropyridinium iodide, benzoyl chloride, acetyl chloride, hydrochloric acid, or trimethylsilyl chloride in organic solvents at room temperature in high yields.Thiadiazoles 2 were also obtained by reaction of 1 with NBS at room temperature in high yields.Thioamide S-oxides reacted with electrophilic reagents at room temperature to give the corresponding thiadiazoles 2 in high yields.
