Sodium hydride → [2-[3,5-bis(Acetoxymethyl)pyrazol-1-yl]-5-nitrophenyl]phenyl methanone

Beteiligte Stoffe

Reaktionsschritte

A solution of 4.2 g. (20 mmol) of 3,5-diacetoxymethylpyrazole in 15 ml. of DMF was added dropwise to a suspension of 960 mg. (20 mmol) of NaH (50% in mineral oil) in 25 ml. of DMF stirred at 0° and under argon. After the evolution of H2 had ceased, 4.9 g. (20 mmol) of 2-fluoro-5-nitrobenzophenone was added in one portion. After stirring at 0° for 4 hours, the mixture was poured into ice-water and extracted with EtOAc. The organic phase was washed with dil. brine, dried (MgSO4) and concentrated. The residue was chromatographed on silica gel using benzene/EtOAc (1:1) as eluent. Removal of the solvents gave crude end product as a gum which was not purified further. The nmr (CDCl3) had signals at: δ2.00 (3H, s, CH3), 2.07 (3H, s, CH3), 4.82 (2H, s, CH2), 5.10 (2 H, s, CH2) 6.33 (1H, s, C=CH), and 7.30-8.67 (8H, m, C6H5 +C6H3).

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