DOI: 10.14469/hpc/11343 Metadata

Created: 2022-10-09 18:01

Last modified: 2024-11-20 09:32

Author: Henry Rzepa

License: Creative Commons: Public Domain Dedication 1.0

Funding: (none given)

Description

1H and 13C primary NMR, IR and crystal data for Bis(ethanol) bis(4-(ethoxycarbonyl)-1-(4-methoxybenzyl)-1H-pyrazol-5-olate)calcium (19): CaCl2 (91.0 mg,0.822 mmol, 1.00 equiv) in H2O and EtOH (1 : 3; 2.0 mL) was added with stirring to pyrazolone 8 (454 mg, 1.64 mmol, 2.00 equiv) in EtOH (3.0 mL) at 79 °C. Aqueous NaOH (2 M; 0.82 mL, 1.64 mmol, 2.00 equiv) was added with stirring and the mixture was heated at reflux for 15 h, cooled to room temperature and H2O (10 mL) was added. The precipitate was collected by filtration and dried in vacuo. Ca-pyrazolone complex 19 (168 mg, 0.247 mmol, 30%) was obtained as a white solid, essentially pure by its 1H NMR spectrum. Crystals suitable for X-ray crystallography were obtained by slow evaporation from an EtOH solution of complex 19. Repeating the reaction with Ca(OTf)2 (210 mg, 0.621 mmol, 1.00 equiv), pyrazolone 8 (343 mg, 1.24 mmol, 2.00 equiv) and aqueous NaOH (2M, 0.62 mL, 1.24 mmol, 2.00 equiv) according to the above procedure resulted in an improved yield of Ca-pyrazolone complex 19 (288 mg, 0.422 mmol, 68%). 1H-NMR (400 MHz, OC(CD3)2): δ (ppm) = 7.33 (s, 1H), 7.14 (d, J = 8.1 Hz, 2H), 6.65 (d, J = 8.1 Hz, 2H), 4.90 (s, 2H), 3.93 (q, J = 7.3 Hz, 2H), 3.68 (s, 3H), 3.56 (q, J = 6.8 Hz, 1H), 1.12 (d, J = 7.1 Hz, 2H), 1.08 (d, J = 7.1 Hz, 3H). 13C{1H}-NMR (101 MHz, OC(CD3)2): δ (ppm) = 168.6, 165.2, 159.5, 138.5, 132.1, 130.2, 114.1, 93.0, 59.8, 57.7, 55.4, 48.3, 18.9, 14.8. IR (Diamond-ATR, neat) νmax (cm-1) = 1638, 1511, 1419, 1464, 1379, 1355, 1318, 1245, 1211,1175, 1030 785. m.p.: 180 – 185 °C (EtOH), >230 °C (decomp.). Anal. Calcd for C28H30CaN4O8 ∙ 2 H2O: C, 53.67; H, 5.47; N, 8.94. Found: C, 53.49; H, 5.45; N, 8.31.

Files

Filename	Size	Type	Description
19.mnova	0	chemical/x-mnova	Mnova data, all spectra
19.mnpub	0	chemical/x-mnpub	Mestrenova signature file for 19.mnova

Member of collection / collaboration

DOI	Description
10.14469/hpc/10386	Syntheses and Characterization of Main Group, Transition Metal, Lanthanide and Actinide Complexes of Bidentate Acylpyrazolone Ligands

Members

DOI	Description
10.14469/hpc/11498	IR data for Compound 19.
10.14469/hpc/11499	NMR Data for Compound 19.
10.14469/hpc/11346	Crystal structure data for Compound 19 Bis(ethanol) bis(4-(ethoxycarbonyl)-1-(4-methoxybenzyl)-1H-pyrazol-5-olate)calcium

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