33655-23-1Relevant academic research and scientific papers
Oxidative rearrangement and cyclisation of N-substituted amidines using iodine(III) reagents and the influence of leaving group on mode of reaction
Ramsden, Christopher A.,Rose, Helen L.
, p. 2319 - 2327 (2007/10/03)
The products of reaction of N-substituted amidines 5 with hypervalent iodine reagents such as (diacetoxyiodo)benzene (DAIB), bis(trifluoroacetoxy)iodobenzene (BFIB) and [methoxy(tosyloxy)-iodo]benzene (MTIB) are determined by the reagent, the amidine substituents and the reaction temperature. C-Alkyl-N-arylamidines 5a-d cyclise in high yield giving benzimidazoles 6 but C,N-dialkyl- and C,N-diaryl-amidines 5e-l rearrange to give products derived from an intermediate carbodiimide. Use of N2-phenylfuran-2-carboximidamide 5j leads to N-(2-furyl)acetamide 15 in good yield, illustrating a convenient route to stable derivatives of highly unstable 2-aminofuran. The rearrangement of C,N-diarylamidines on reaction with DAIB contrasts with the observed formation of benzimidazole when the same precursors are treated with lead tetraacetate (LTA). Evidence is presented to support the view that the mode of reaction is determined by the nature of the leaving group in an imide intermediate 19: very good leaving groups [e.g. PhI, N2, AgCl and PhSO2O- (aq.)] appear to favour rearrangement whereas poorer leaving groups [e.g. Cl-, Me2S, Me3N and PhSO2O- (non-aq.)] favour cyclo-α-elimination.
Rearrangement and cyclo-α-elimination of N-substituted amidines using (acetoxyiodo)benzene
Ramsden, Christopher A.,Rose, Helen L.
, p. 615 - 618 (2007/10/02)
The products of reaction of N-substituetd amidines with (diacetoxyiodo)benzene are determined by the nature of the amidine substituents and the reaction temperature: rearrangement of N2-phenylfuran-2-carboximidamide provides a convenient route to N-(2-furyl)acetamide, whereas N-phenyl C-alkyl formimidamides cyclise to give benzimidazoles in good yield.
Reactions of Phenylbenzamidines with Isocyanates and Isothiocyanates
Nair, M. D.,Desai, J. A.
, p. 20 - 23 (2007/10/02)
The reaction of N-aryl benzamidines with phenyl isocyanate (phenyl isothiocyanate) yields the normal adducts, quinazoline-4-ones (4-thiones) or diphenyl ureas (thioureas) depending on the substituent on the aryl group and the reaction conditions.The mechanisms of the various transformations are discussed.
