Compound 43: bis((4-benzoyl-1-(4-methoxybenzyl)-1H-pyrazol-5-yl)oxy)manganese

Bis(ethanol) bis((4-benzoyl-1-(4-methoxybenzyl)-1H-pyrazol-5-yl)oxy)manganese (43): Bis(ethanol) bis((4-benzoyl-1-(4-methoxybenzyl)-1H-pyrazol-5-yl)oxy)manganese (43): Mn(OAc)2 (49.0 mg, 0.281 mmol, 1.00 equiv) was added with stirring to pyrazolone 10 (173 mg, 0.561 mmol, 2.00 equiv) in EtOH (6.5 mL) at 79 °C. The mixture was heated at reflux for 4 h, cooled to room temperature, Et2O was added (15 mL), and the precipitate was collected by filtration and dried in vacuo. Mn-pyrazolone complex 43 (141 mg, 0.185 mmol, 65%) was obtained as a white solid. Crystals suitable for X-ray crystallography were obtained by slow evaporation from an EtOH solution of complex 43. IR (Diamond-ATR, neat) νmax (cm-1) = 1601, 1577, 1521, 1508, 1497, 1486, 1438, 1415, 1375, 1240, 1172, 1027, 898, 800, 758, 710, 699. m.p.: >288 °C (EtOH) (decomp.). Anal. Calcd for C36H30MnN4O6 ∙ 0.2 MnO: C, 63.24; H, 4.42; N, 8.19. Found: C, 63.99; H, 4.15; N, 7.98.