Nagata reagent

Nicolaou et al. used the same sulfonate ester system to prove the compatibility of sulfonate esters with carbon-carbon bond-forming reactions [305]. Functionalization and a simultaneous cleavage procedure have been applied successfully by the use of Grignard reagents 585, the Nagata reagent 583 and stannane as well as lithium organic compounds (579, 581). All compounds namely a-allyl ketone 580, epoxide 582, a-cyano ketone 584 and carbinol 586 could be isolated in 65-85% yield (Scheme 85). 

A simple and rapid method of separating optical isomers of amino acids on a reversed-phase plate, without using impregnated plates or a chiral mobile phase, was described by Nagata et al. [27]. Amino acids were derivatized with /-fluoro-2,4-dinitrophenyl-5-L-alanine amide (FDAA or Marfey s reagent). Each FDAA amino acid can be separated from the others by two-dimensional elution. Separation of L- and D-serine was achieved with 30% of acetonitrile solvent. The enantiomers of threonine, proline, and alanine were separated with 35% of acetonitrile solvent and those of methionine, valine, phenylalanine, and leucine with 40% of acetonitrile solvent. The spots were scraped off the plate after the... 

The problem of the hydrocyanation of conjugated carbonyl compounds has been reviewed in detail by Nagata and Yoshioka [281. The reactions proceed smootltly and base or acid catalysts are sometime useful with HCN. Cyanides (KCN. NaCN. etc.) arc recommended reagents in some cases, particularly in nonaqueous Solvents (28], and even cyanohydrins (e.g., acetone cyanohydrin) have been used as cyanation reagents. 

Nagata, W., Yoshioka, M. Hydrocyanation. III. Alkylaluminum cyanides as potent reagents for hydrocyanation. Tetrahedron Lett. 1966, 1913-1918. 

Nagata S, HamasaM T, Uetake K et al (2010) Synthesis and biological activity of artificial mRNA prepared with novel phosphorylating reagents. Nucleic Acids Res 38 7845-7857... 

So far, no example of reduction has been reported in the literature using a catalytic system relying on planar chirality. However, ansa-derivatives of Hantzsch esters were developed by Kanomata and Nagata [58] as NADH model compounds (Scheme 8.20). These reagents displayed excellent hydrogen transfer abilities-reduction of carbonyl compounds was achieved with almost perfect enantioselec-tivily. There is no doubt that, coupled with a proper metal-based hydride-transfer system, such NADH models could perform well in a catalytic version. 

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