Kornblum aldehyde synthesi

KONIG Benzoxazin synthesis 214 KORNBLUM Aldehyde synthesis 215 KOSER Tosylation 216 Kostaneeki 321... 

Kornblum aldehyde synthesis. 1-Iodoheptane added at 0-5° to a soln. of Ag-tosylate in acetonitrile protected from light, allowed to come to room temp, overnight, the resulting crude tosylate added at 150° to a freshly prepared mixture of NaHGOg and dimethyl sulfoxide through which Ng is passed, and cooled rapidly to room temp, after 3 min. at 150°-> n-heptaldehyde. Y 70% as the 2,4-dinitrophenylhydrazone.—Similarly at 100° during 5 min. p-Bromo-benzyl bromide p-bromobenzaldehyde. Y 76% as the 2,4-dinitrophenylhydrazone. F. e. s. N. Kornblum, W. J. Jones, and G. J. Anderson, Am. Soc. 81, 4113 (1959). 

Evans and Mitch( 101 elaborated this synthesis to afford a general approach to morphinans and to include a total synthesis of ( )-morphine (Scheme 3.7). The diastereomerically pure aziridinium salt, 43, was prepared as illustrated and converted to the aldehyde (44) in 95% yield simply by dissolving in anhydrous DMSO at ambient temperature (Kornblum oxidation). Lewis acid catalyzed ring closure occurred in high yield (80%) to the isomorphinan-10-ol... 

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. 

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