Modified Kornblum

The first total synthesis of the clerodane alkaloid solidago alcohol was achieved in the laboratory of H.-S. Liu, using a highly diastereoselective DIels-Alder cycloaddition as the key step. The installation of the 3-furyl side chain required the conversion of the bicyclic primary alkyl bromide to the corresponding aldehyde. This was accomplished by the modified Kornblum oxidation, which employed silver tetrafluoroborate to activate the substrate. 

The synthesis of aliphatic nitro compounds from the reaction of alkyl halides with alkali metal nitrites was discovered by Kornblum and co-workers and is known as the modified Victor Meyer reaction or the Kornblum modification. The choice of solvent in these reactions is crucial when sodium nitrite is used as the nitrite soiuce. Both alkyl halide and nitrite anion must be in solution to react, and the higher the concentration of nitrite anion, the faster the reaction. For this reason, both DMF and DMSO are widely used as solvents, with both able to dissolve appreciable amounts of sodium nitrite. Although sodium nitrite is more soluble in DMSO than DMF the former can react with some halide substrates.Urea is occasionally added to DMF solutions of sodium nitrite to increase the solubility of this salt and hence increase reaction rates. Other alkali metal nitrites can be used in these reactions, like lithium nitrite,which is more soluble in DMF than sodium nitrite but is also less widely available. 

The traditional oxidation of benzylic and other halides to the aldehyde using DMSO (Kornblum oxidation) has been known for about 35 vears246,362,363. Modified oxidations of this type using selenoxides364,365 and 2-nitropropane366,367 have proved more versatile since other functional groups that are sensitive to the traditional oxidation procedure may be tolerated. In the reaction with 2-nitropropane, allylic halides are readily converted into aldehydes with retention of the alkene geometry. 

Novel fluorescent ATP analogues where the two tertiary carbons of the etheno-moiety of A A -etheno adenosine have been modified by the introduction of a /7-nitro or a / -amino-phenyl group and a hydroxy moiety (100) have been prepared via a Kornblum oxidation reaction and imidazole formation. These compounds exhibited relative stability towards type II ATPDase. ... 

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