cas 5203-80-5, 1-Acetyl-1H-indazol-3-ol acetate

Articles about 5203-80-5Total 4 be found

Kinetically deduced existence of C=O·····C close contacts. Pericyclic rearrangement of 1,2-diacetyl-1,2-dihydro-3H-indazol-3-one
First-order kinetics of the title rearrangement to 3-acetoxy-1-acetylindazole (2a), complete exchange of O-acyl groups in cross-experiments, insensitivity to change in reaction medium, lack of electronic substituent effects and activation parameters are considered as evidence in favour of a pericyclic mechanism through C=O·····C close contacts.
Dumitrascu, Florea,Raileanu, Dan
p. 1295 - 1298
(2007/10/02)

REVERSE MUMM REARRANGEMENTS. I. THERMOLYSIS OF 3-ACETOXY-1-FORMYLINDAZOLE
2-Acetyl-3-indazolone (15), 1,2-diacetyl-3-indazolone (16) and 3-acetoxy-1-acetylindazole (3) are intermediates of the title thermolysis which leads to 1-acetyl-3-indazolone (4). The rearrangement of 16 to 3 is a reverse Mumm rearrangement which has not yet been observed. The same pattern applies to the acetylation of the 3-indazolone (2). Acylotropic equilibria have been observed between 2-acetyl-1-methyl-3-indazolone (24) and 3-acetoxy-1-methylindazole (26).
Dumitrascu, Florea,Raileanu, Dan
p. 1247 - 1258
(2007/10/03)

NEW CONVENIENT METHODS FOR THE SYNTHESIS OF 1,2-DIHYDRO-3H-INDAZOL-3-ONE AND ITS 1-ACYL DERIVATIVES
The acid hydrolysis of the readily obtainable 3-(o-carboxyphenyl)sydnones (6a-d) afforded 3-indazolones (3a-d) in yields over 90 percent. By transacylation between 1-acyl-3-acyloxyindazoles (11a-d) and 3-indazolones (3a, c), the corresponding 1-acyl-3-indazolones 10a-d resulted in pure state and yields also over 90 percent.
Dumitrascu, Florea,Plaveti, Marieta,Raileanu, Dan
p. 917 - 924
(2007/10/03)

Acyl Derivatives of Indazolin-3-one
1- and 2-Ethanoyl-, propanoyl-, butanoyl- and benzoylindazolin-3-ones have been prepared and the 2-isomers have been shown to exist in two tautomeric forms.Sulphonylation and further acylation of these compounds are described and some rearrangements in the series are discussed.
Anderson, Robert M.
p. 3933 - 3959
(2007/10/02)