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12.1.4.1.1.2 Method 2: Metalation of Pyrazoles

DOI: 10.1055/sos-SD-012-00002

Stanovnik, B.; Svete, J.Science of Synthesis, (200212169.

1-Unsubstituted 1H-pyrazoles 401 react with strong bases to form metal pyrazolides. Alkali metal pyrazolides and silver pyrazolides 402 are of preparative importance (Scheme 225).[‌9‌,‌16‌,‌55‌,‌728‌‌733‌] Lithium, sodium, and potassium pyrazolides are readily prepared from 1-unsubstituted 1H-pyrazoles, e.g. formation of 403.[‌734‌] Instead of sodium, sodium hydride in tetrahydrofuran[‌728‌] or in 1,2-dimethoxyethane,[‌735‌] or sodium ethoxide can be used for metalation.[‌736‌]

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