89332-93-4Relevant academic research and scientific papers
Studies on chromone derivatives: regioselective 1,3-dipolar and 1,4-cycloaddition reactions of 3-cyano-4H-1-benzopyran-4-thione
Sain, Bir,Prajapati, Dipak,Mahajan, Asha R,Sandhu, Jagir S
, p. 313 - 316 (2007/10/02)
1,3-Dipolar cycloaddition reactions of 3-cyano-4H-1-benzopyran-4-thione 1 with nitrilimines 3, nitrile oxides 7 and aldonitrones 8 yielded regioselective cycloadducts involving the thione function.In the latter two classes, the unstable cycloadducts fragmented to yield 3-cyanochromone 11 and isothiocyanate 12 or thioamide 13, respectively.In contrast, dienamines 14 preferred to react at the carbon-carbon double bond in a 1,4-cycloaddition yielding xanthione (9H-xanthene-9-thione) 16 by elimination of HCN and the amine moiety.Keywords: 1,3-dipolar cycloaddition / 1,4-cycloaddition / 4H-1-benzopyran-4-thione / nitrilimine / nitrile oxide / nitrone
SOME NOVEL ASPECTS OF REGIOSELECTIVITY IN 1,3 DIPOLAR CYCLOADDITIONS OF 4H-1-BENZOPYRAN-4-THIONE
Baruah, Arpan K.,Prajapati, Dipak,Sandhu, Jagir S.
, p. 6137 - 6142 (2007/10/02)
4H-1-Benzopyran-4-thione (1) reacted smoothly with nitrilimines (3a-e) to afford regioselective cycloadducts (4a-e) in good yields.In contrast,benzonitrile oxide (6) and aldonitrones (7a-d) reacted preferentially at the thione function.The unstable cycloadduct (8) or (9) ruptured to give as isolable products chromone (10) and phenyl isothiocyanate (11) and the thioamides (12a-d).This indirectly proves the site of attack of the dipole at the thione group.
Utilization of thiocarbonyl transfer reagents. Preparation of thioamides, mercapto esters, and thiapyran derivatives
Harpp, David N.,MacDonald, J. Gavin,Larsen, Charles
, p. 951 - 957 (2007/10/02)
The reaction of 1,1'-thiocarbonyldiimidazole and 1,1'-thiocarbonylbis(1,2,4-triazole) with several aldonitrones has been found to afford thioamides in good yield.Several 1,1'-thiocarbonylbisazoles, which have been shown to undergo Diels-Alder additions wi
SYNTHESIS OF THIOAMIDES FROM ALDONITRONES UTILIZING THIOCARBONYL TRANSFER REAGENTS
Harpp, David N.,MacDonald J. Gavin
, p. 4927 - 4930 (2007/10/02)
The reaction of 1,1'-thiocarbonyldiimidazole and 1,1'-thiocarbonylbis(1,2,4-triazole) with several aldonitrones has been found to afford thioamides in good yield.The effect of solvent polarity and base is discussed.
