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2-Nitrobenzenesulfonylhydrazide, NBSH

2-Nitrobenzenesulfonylhydrazide can easily be prepared from the corresponding sulfonyl chloride and hydrazine hydrate according to a method reported by Myers (J. Org. Chem. 1997, 62, 7507. DOI) and can be stored at -20C under nitrogen for 2 months. A one pot protocol for the formation of NBSH and subsequent alkene reduction has been reported (see recent literature).

NBSH (o-nitrobenzenesulfonylhydrazide) generates diimide in polar solvents by in situ elimination of o-nitrobenzenesulfinic acid at room temperature and neutral pH. These mild reaction conditions for the generation of diimide are very attractive for substrates containing sensitive groups.

Diimide efficiently reduce alkenes without alkene isomerization and epimerization and offers a unique chemoselectivity.

Recent Literature

A one-pot protocol for the formation of 2-nitrobenzenesulfonylhydrazide (NBSH) from commercial reagents and subsequent alkene reduction is operationally simple and generally efficient. A range of 16 substrates have been reduced, highlighting the unique chemoselectivity of diimide as a alkene reduction system.
B. J. Marsh, D. R. Carbery, J. Org. Chem., 2009, 74, 3186-3188.

Mitsunobu displacement of an alcohol with o-nitrobenzenesulfonylhydrazide followed by in situ elimination of o-nitrobenzenesulfinic acid generates monoalkyl diazenes, which decompose by a free-radical mechanism to form deoxygenated products.
A. G. Myers, M. Movassaghi, B. Zheng, J. Am. Chem. Soc., 1997, 119, 8572-8573.