Sodium hydrazide, reduction

Reductive cleavage 0/olefins. In refluxing ether under nitrogen, sodium hydrazide reductively cleaves olefins of the type (1). Yields of the nitrogen-free products (3) are as a rule over 80%. An isolated double bond is not attacked. 

Dibromobenzo[6]thiophene and its 6-carboxylic acid undergo bisdehalogenation on treatment with sodium hydrazide and hydrazine 515 and on catalytic reduction in alkaline solution,77 respectively. Bromonitrobenzo[6]thiophenes readily undergo debromination on treatment with copper and quinoline,412 copper bronze and benzoic acid,84 or tin and hydrochloric acid.516... 

Mixtures of 1,3,5- and 1,3,6-cyclooctatriene were obtained by partial reduction of cyclooctatetraene in ways such as protonation of cyclooctatetraene dianion3d-4 and reduction with zinc-alkali.2 5 1,3,6-Cyclooctatriene is the major product in these reductions. However, since 1,3,6-cyclooctatriene isomerizes to 1,3,5-cyclooctatriene on treatment with base, quenching cyclooctatetraene dianion with methanol and subsequent heating affords 1,3,5-cyclooctatriene in an 80% yield.3d Reduction of cyclooctatetraene with sodium hydrazide and hydrazine also produces 1,3,5-cyclooctatriene.6 Therefore, when cyclooctatetraene is available in quantity, these procedures are the methods of choice. 

Reduction by sodium hydrazide is a variant of hydrazine reduction for which the possible occurrence of diimine is not yet decided.102,114 This reagent does... 

Sodium amide/hydrazine Reductions with sodium hydrazide/hydrazine NaNH IHsN NH ... 

Putrescine dihydrochloride has been prepared by the Hofmann degradation of adipamide 3.. s by the Curtius degradation of adipyl hydrazide through the urethane by the Curtius degradation of adipyl azide obtained from adipyl chloride and sodium azide by the Schmidt degradation of adipic acid with hydrogen azide by the reduction of succinonitrile, succinaldoxime, or 7-phthalimidobutyronitrile with sodium and from N-ben-zoyl-7-iodobutylamine ... 

Aldehyde-containing macromolecules will react spontaneously with hydrazide compounds to form hydrazone linkages. The hydrazone bond is a form of Schiff base that is more stable than the Schiff base formed from the interaction of an aldehyde and an amine. The hydrazone, however, may be reduced and further stabilized by the same reductants utilized for reductive amination purposes (Chapter 3, Section 4.8). The addition of sodium cyanoborohydride to a hydrazide-aldehyde reaction drives the equilibrium toward formation of a stable covalent complex. Mallia (1992) found that adipic acid dihydrazide derivatization of periodate-oxidized dextran (containing multiple formyl functionalities) proceeds with much greater yield when sodium cyanoborohydride is present. 

Another route to the formation of a hydrazide on a surface is to use an aldehyde-containing particle (such as HEMA/acrolein copolymers) and subsequently modify the aldehydes to form hydrazone linkages with bis-hydrazide compounds, which then can be stabilized by reduction with sodium cyanoborohydride (Chapter 2, Section 5). The resulting derivative contains terminal hydrazides for immobilization of carbonyl ligands (see Figure 14.18). 

Aldehyde particles are spontaneously reactive with hydrazine or hydrazide derivatives, forming hydrazone linkages upon Schiff base formation. Reactions with amine-containing molecules, such as proteins, can be done through a reductive amination process using sodium cyanoborohydride (Figure 14.21). 

In a fume hood, add 10 pi of 5M sodium cyanoborohydride (Sigma) per ml of reaction solution. Caution Cyanoborohydride is extremely toxic. All operations should be done with care in a fume hood. Also, avoid any contact with the reagent, as the 5M solution is prepared in IN NaOH. The addition of a reductant is necessary for stabilization of the Schiff bases formed between an amine-containing protein and the aldehydes on the antibody. For coupling to a hydrazide-activated protein, however, most protocols do not include a reduction step. Even so, hydrazone linkages may be further stabilized by cyanoborohydride reduction. The addition of a reductant during hydrazide/aldehyde reactions also increases the efficiency and yield of the reaction. 

The keto group in condensed 4//-pyran derivative 264 was successfully reduced by reduction of the tosyl hydrazide with sodium borohydride.290... 

Nitrophenyl)hydrazides (468) give 1,2-dihydro-1,2,4-benzotriazines (469) with sodium amalgam in ethanol. In most cases the initial dihydro compounds (469) are oxidized by potassium ferricyanide to the aromatic 1,2,4-benzotriazines (470) (78HC(33)189). Similarly, reduction of the nitrohydrazones (471) affords 1,2,4-benzotriazines (470) (78HC(33)189, p. 666). 

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