Next Article in Journal
Previous Article in Journal
Molecules 2006, 11(11), 867-889; doi:10.3390/11110867
Article

Synthesis and Structural Characterization of 1- and 2-Substituted Indazoles: Ester and Carboxylic Acid Derivatives

1,* , 1, 1, 1, 2 and 3
Received: 4 October 2006; in revised form: 30 October 2006 / Accepted: 13 November 2006 / Published: 14 November 2006
Download PDF [171 KB, uploaded 18 June 2014]
Abstract: A series of indazoles substituted at the N-1 and N-2 positions with ester-containing side chains -(CH2)nCO2R of different lengths (n = 0-6, 9, 10) are described.Nucleophilic substitution reactions on halo esters (X(CH2)nCO2R) by 1H-indazole inalkaline solution lead to mixtures of N-1 and N-2 isomers, in which the N-1 isomerpredominates. Basic hydrolysis of the ester derivatives allowed the synthesis of thecorresponding indazole carboxylic acids. All compounds were fully characterised bymultinuclear NMR and IR spectroscopies, MS spectrometry and elemental analysis; theNMR spectroscopic data were used for structural assignment of the N-1 and N-2 isomers.The molecular structure of indazol-2-yl-acetic acid (5b) was determined by X-raydiffraction, which shows a supramolecular architecture involving O2-H...N1intermolecular hydrogen bonds.
Keywords: Indazole; N-1 and N-2 isomers; Spectroscopic characterization; X-ray diffraction studies. Indazole; N-1 and N-2 isomers; Spectroscopic characterization; X-ray diffraction studies.
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Export to BibTeX |
EndNote


MDPI and ACS Style

Teixeira, F.C.; Ramos, H.; Antunes, I.F.; Curto, M.J.M.; Duarte, M.T.; Bento, I. Synthesis and Structural Characterization of 1- and 2-Substituted Indazoles: Ester and Carboxylic Acid Derivatives. Molecules 2006, 11, 867-889.

AMA Style

Teixeira FC, Ramos H, Antunes IF, Curto MJM, Duarte MT, Bento I. Synthesis and Structural Characterization of 1- and 2-Substituted Indazoles: Ester and Carboxylic Acid Derivatives. Molecules. 2006; 11(11):867-889.

Chicago/Turabian Style

Teixeira, Fátima C.; Ramos, Hélène; Antunes, Inês F.; Curto, M. J.M.; Duarte, M. T.; Bento, Isabel. 2006. "Synthesis and Structural Characterization of 1- and 2-Substituted Indazoles: Ester and Carboxylic Acid Derivatives." Molecules 11, no. 11: 867-889.



Molecules EISSN 1420-3049 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert