Related Reducing Agents

Bu3SnH reacts spontaneously at ambient temperature with acid chlorides in a non-radical process, whereas (TMS)3SiH does not. Therefore, acid chlorides can be used under free-radical conditions only with the silane. 

The denitration of tertiary nitroalkanes by Bu3SnH is an efficient process [27]. (TMS)3SiH is not able to reduce tertiary nitroalkanes to the corresponding hydrocarbons [77]. This behavior is due to the fact that the nitroxide adducts fragment preferentially at the nitrogen-oxygen bond rather than at the carbon-nitrogen bond. 

Thioacetals, selenoacetals and their analogs have been studied in some detail [8], and an example of reverse product stereoselectivities of the two reducing agents is shown in Eq. (38) [78]. The silicon hydride approaches from the less hindered equatorial position to give trans/cis ratios of 30/70, whereas Bu3SnH transfers a hydrogen atom preferentially from the axial position. 

BuaSnH/PhSeH system [83]. It was found that undesired radical rearrangements, which are sufficiently rapid to proceed in the presence of the tin hydride alone, can be suppressed in the presence of PhSeH. 

The facts that thiols are good H-atom donors toward alkyl radicals and that silyl radicals are among the most reactive known species for abstraction and addition reactions suggest that any class of compounds which allows the transformation of a thiyl to a silyl radical via a fast intramolecular rearrangement will potentially be a good radical-based reducing agent. The silanethiols 11 and 12 are found to have this property [84, 85]. The reductions of bromides, iodides and isocyanides by thiol 12 are demonstrated to follow the expected mechanism [85]. 

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Hajos, A. 1979, Complex Hydrides and Related Reducing Agents in Organic Synthesis, Elsevier Amsterdam New York... 

Reductive dehalogenation of polyhaloketones with low-valence metals and related reducing agents 83OR(29) 163. 

Reductive Dehalogenation of Poiyhalo Ketones with Low-Valent Metals and Related Reducing Agents Ryoji Noyori and Yoshihiro Hayakawa... 

When comparison is made between LiAIFLj and related reducing agents containing active Al-H and B-H bonds, LiAlHa is seen to be the most broadly effective (Table 1). Its superior reducing power is also reflected in its speed of hydride transfer. 

By far the largest number of applications of polymeric materials in the field of biochemistry have been associated with enzyme and whole cell immobilization, affinity and covalent chromatography, and the immobilization of biologically-related reducing agents. 

Benzylidenebenzylamine added to 7,8-dihydro-7,9-dimethylxanthine in methanol containing acetic acid, refluxed 3 hrs., and kept overnight at room temp. di-benzylamine. Y 82%. F. e. and related reducing agents s. S. M. Hecht, B. L. Adams, and J. W Kozarich, J. Org. Chem. 41, 2303 (1976). 

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