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p-Toluenesulfonyl hydrazide is used as a reagent for the preparation of tosylhydrazones. It was used to prepare dipyrazolo[1,5-a:4?,3?-c]pyridines and 1,2,3-selenadiazole derivatives.
Robert O. Hutchins.; Bruce Maryanoff.; Cynthia Milewski. Selective reduction of aliphatic ketones and aldehydes to hydrocarbons with sodium cyanoborohydride and p-toluenesulfonyl hydrazide in dimethylformamide-sulfolane. J. Am. Chem. Soc. 1971, 93, (7), 1793-1794.
Panagiotis Dounis.; James Feast, W. A route to low polydispersity linear and star polyethylenes via ring-opening metathesis polymerization. Polymer. 1996, 37, (12), 2547-2554.
Precursor of the versatile synthetic intermediates, tosylhydrazones. For a brief feature on tosylhydrazones, see: Synlett, 1844 (1999). Preparation using AcOH rather than mineral acid was found to reduce azine formation: Synthesis, 957 (1984).
Several simple methods are known for cleavage of tosylhydrazones, including:
Exchange with refluxing acetone: J. Org. Chem., 40, 3302 (1975); acetone/ BF3 etherate: Synthesis, 456 (1976); Amberlyst® 15 in aqueous acetone: J. Chem. Soc., Perkin 1, 2563 (1988).
Reduction of tosylhydrazones to alkanes by NaBH4 is a mild alternative to the Clemmensen and Wolff-Kishner methods: Chem. Ind. (London), 153, 1689 (1964). NaBH4 in AcOH is a more selective system: J. Org. Chem., 43, 2299 (1978). For reduction of a steroidal ketone by catecholborane, see: Org. Synth. Coll., 6, 293 (1988). Aliphatic tosylhydrazones are also reduced to methylenes by NaBH3CN, effective even for hindered ketones. For a study of the mechanism of this reduction, see: J. Org. Chem., 54, 4175 (1989).
Reaction of tosylhydrazones with base leads to alkenes (Bamford-Stevens reaction): J. Chem. Soc., 4735 (1952). Dianion formation from the tosylhydrazone with an alkyllithium or LDA results in a vinyllithium intermediate, which, on protonation, also gives the alkene (Shapiro-Heath reaction). With unsymmetrical tosylhydrazones, this is a useful synthesis of the less-substituted of the two possible alkenes: J. Am. Chem. Soc., 89, 5734 (1967); J. Org. Chem., 43, 1404 (1978):
For a reviews of the Bamford-Stevens, Shapiro-Heath and related reactions, see: Org. React., 23, 405 (1976); 39, 1 (1990). For an example (bornene: 63-66% yield from camphor tosylhydrazone and MeLi), see: Org. Synth. Coll., 6, 172 (1988).
Gefahrenhinweise (EU): H228-H242-H301
Flammable solid. Heating may cause a fire. Toxic if swallowed.
Keep away from heat/sparks/open flames/hot surfaces. - No smoking. Wear protective clothing. IF exposed or if you feel unwell: