Sodium cyanotrihydroborate

Although infrequently used, sodium cyanotrihydroborate in the presence of BF3 has been shown to reduce epoxides with interesting regio- and stereo-chemical results. For example, 1-methylcyclohexene oxide is converted in high yield to c/s-2-methylcyclohexanol contaminated with only small amounts of the n ans and 1-methylcyclohexanol isomers. 

NaBHjCN (sodium cyanotrihydroborate), or electrochemical reduction to generate hydrides of As, Se, Bi, Sn, Sb, Ge, and Pb. These are then swept into either a flame directly or into a flame- or electrically heated tube for atomization. Atomization of the gaseous hydrides occurs in argon (or nitrogen)-hydrogen diffusion flame, electrically-heated quartz tube, flame-heated quartz tube (quartz tube atomizers QTA), flame-in-tube (FIT) atomizer or a graphite furnace. Other techniques of chemical vapor generation can be as chlorides, Ni carbonyl, tetramethyl lead or chelates. 

Most recently, amineboranes of the type L-BH3 (where L = NH3 tert-BuNHz MezNH Me3N) and sodium cyanotrihydroborate(III) (NaBH3CN) have been tested for efficacy of generation of elemental mercury and volatile hydrides of As(III), As(V), Sb(III), Sb(V), Bi(ni), Se(IV), Se(VI), Te(IV), and Te(VI). All of the reductants are suitable for efficient generation of cold-vapor mercury but only some of the amineboranes are suitable for hydride generation,... 

Activation of the functionalized support is most often achieved with glutaraldehyde, which introduces a carbonyl residue that subsequently reacts with nucleophilic groups on the enzyme. The activation of the functional material and the biding of the enzyme result in the formation of a Schiff base. The optimum pH for these reactions is a compromise between the preferred acidic catalytic conditions, the of the nucleophilic groups (in such a way that the unpro-tonated form is desirable) and the stability of the enzyme at different pH values. The reversibility of Schiff base formation is suppressed by the addition of sodium cyanotrihydroborate, a weak reducing agent, which does not reduce aldehydes or ketones at neutral pH but readily reduces the imine form to the... 

The cyanoborane derivatives were prepared from the corresponding polyamine hydrochlorides in aqueous media using a procedure similar to that described in ref [7]. Hydrogen evolved in the reaction between the hydrochloride and sodium cyanotrihydroborate was measured with a wet test meter. An alternative synthetic approach to prepare the cyanoborane derivative of PEI that did not produce sodium chloride by-product used a transamination reaction between neutral PEI and pyridine cyanoborane. 

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