N- 2-Hydroxyethyl -3,5-dimethylpyrazole

Solvents and reagents (2,4-pentanedione, 2-hydroxyethylhydrazine, copper bromide, p-toluenesulfonylchloride) are available from the common commercial sources. 

The product V-(2-hydroxyethyl)-3,5-dimethylpyrazole is easily obtained as large, colorless crystals. Varying the ratio of ether and acetone used in 

The compound [Cu(N-oed)Br]2 readily crystallizes from the reaction mixture, resulting in dark green, X-ray quality single crystals.9 The two copper ions in the dinuclear unit are 3.0 A apart, bridged by the two oxo atoms from the ligands. Each copper ion is in a square planar 02NBr environment, with 

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The present paper describes the synthesis of N-(2-hydroxyethyl)-3,5-dimethylpyrazole and the synthesis of the tosylated compound N-(2-p-tol-uenesulfonylethyl)-3,5-dimethylpyrazole which can be used for the synthesis of larger chelating ligands. The tosylation is carried out in a water/acetone mixture, unlike most classical tosylations, which are performed in pyridine.7 A high yield of pure tosylated product is obtained from this reaction. A water/acetone mixture as the solvent for the synthesis of other tosylates may very well be also successful. Since the compound N-(2-hydroxyethyl)-3,5-dimethylpyrazole may itself act as a didentate N,0 ligand in coordination compounds with transition metal ions,9 an example using Cu(II) is provided below. 

N-(2-hydroxyethyl)-3,5-Dimethylpyrazole, a Dinuclear Copper Complex 83 Starting Materials... 

JV-(2-HYDROXYETHYL)-3,5-DIMETHYLPYRAZOLE, A DINUCLEAR COPPER COMPLEX, AND N-(2-p-TOLUENESULFONYLETHYL)-3,5-DIMETHYLPYRAZOLE... 

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