1202-42-2Relevant academic research and scientific papers
Novel synthesis of 1-substituted-4-imidazolecarboxylates via solvent-free cycloaddition reaction between formamidines and isocyanides
Cao, Han,Bie, Fu-sheng,Liu, Xue-jing,Han, Ying,Ma, Jie,Shi, Yi-jun,Yan, Peng,Sun, Chao-yue,Wang, Hai-meng
, (2020/04/27)
A simple and efficient protocol for cyclization between formamidines and ethyl isocyanoacetate has been described in the absence of metal catalyst and solvent. A series of 1-substituted-4-imidazolecarboxylates were synthesized in moderate to good yields with DABCO as base additive.
N, N-diisopropylformamidine (DIFA) protection of anilines in metalation reactions
Zhichkin, Paul E.,Krasutsky, Sergiy G.,Krishnamoorthy, Ravi
supporting information; experimental part, p. 3039 - 3044 (2011/02/25)
A novel N,N-diisopropylformamidine (DIFA) protecting group for anilines was studied. Metalation is often metal-directed by this weakly coordinating and bulky group, making it complementary to ortho-metalation directed by tert-butylcarbamate and pivaloylam
Amidines. Part 31. pKa Values of N1,N1-Dialkyl-N2-phenylformamidines in Water-Ethanol Solutions
Oszczapowicz, Janusz,Jaroszewska-Manaj, Jolanta
, p. 1677 - 1680 (2007/10/02)
The pKa values of three series (30 compounds in all) of N1,N1-dialkyl-N2-phenylformamidines (XC6H4N=CHNRR) have been measured in water-ethanol mixtures.The obtained pKa values of the amidines have been correlated with Hammett-type substituent constants and the pKa values of the corresponding primary amines determined in the same solvent.The applicability of various ? values is discussed and it is shown that, in each case, for substituents on the phenyl ring at the amino nitrogen atom ?0 values should be used.It is found that the slopes of regression lines for correlations with Hammett-type constants depend on the substituents at the amino nitrogen atom, as well as on the solvent.
Amidines. Part 20. Rate of Reaction of N,N-Dialkylformamide Acetals with Substituted Anilines
Osek, Jerzy,Oszczapowicz, Janusz,Drzewinski, Witold
, p. 1961 - 1964 (2007/10/02)
Rate of reaction of seven N,N-dialkylformamide acetals R2N-CH(OR2)2 with a series of anilines substituted on the phenyl ring have been measured in benzene, methanol, chloroform, and tetrahydrofuran by use of a g.l.c. method.In each case studied reaction is irreversible and obeys a second-order kinetic equation.Reaction rates correlate with Hammett ? constants for substituents on the phenyl ring of the aniline molecule.On the basis of the kinetic data, the mechanism of reaction is discussed.
AMIDINES.PART XI. BASICITY OF N1,N1-DIMETHYLFORMAMIDINES
Oszczapowicz, Janusz,Raczynska, Ewa
, p. 419 - 428 (2007/10/02)
The pKa values of twenty four N1,N1-dimethyl-N2-phenyl- and N1,N1-dimethyl-N2-alkyl-formamidines in 95.6percent ethanol (azeotrope) at 25+/-0.2 degC have been measured by the potentiometric method.The pKa values of N2-phenyl derivatives obey Hammett equation and obtained ρ value is ca. 2/3 of that for symmetrically disubstituted N,N'-diphenylformamidines.It is shown that there is a good correlation, common for both N2-alkyl as well as for N2-aryl formamidines between pKa values of dimethylformamidines and pKa of corresponding primary amines.The slope of this correlation line is also ca. 2/3 of that for symmetricall y disubstituted N,N'-dialkyl- and N,N'-diarylformamidines.Experimental conditions securing reliable results of pKa determinations by potentiometric method in ethanol are discussed.
A Versatile New Synthesis of Quinolines and Related Fused Pyridines. Part 7. The Conversion of Acetamidothiophens into Thienopyridines
Meth-Cohn, Otto,Narine, Brahma,Tarnowski, Brian
, p. 1531 - 1536 (2007/10/02)
5-Substituted-2-acetamidothiophens are converted into 2-acetamidothiophen-3-carbaldehydes in good yield with equimolar amounts of dimethylformamide and phosphoryl chloride in hot dichloroethane.However, under similar conditions but with three mol of phosp
