Diazoaldehyde chemistry .4. Vilsmeier-Haack formylation of diazo compounds: A re-investigation


Sezer O. , Dabak K., Anac O., Akar A.

HELVETICA CHIMICA ACTA, vol.80, no.3, pp.960-965, 1997 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 80 Issue: 3
  • Publication Date: 1997
  • Doi Number: 10.1002/hlca.19970800327
  • Title of Journal : HELVETICA CHIMICA ACTA
  • Page Numbers: pp.960-965

Abstract

Diazomethyl ketones (2-diazoethanones) were reacted with the Vilsmeier reagent ((chloromethylide)dimethylammonium chloride)to yield alpha-diazo-beta-oxoaldehydes and chloromethyl ketones. 2',4'-Dimethoxy-alpha-diazoacetophenone gave 2-chloro-1-(2,4-dimethoxyphenyl)-3-(dimethylamino)prop-2-en-1-one (5) in addition to the expected products. Phenyldiazomethanes gave the corresponding benzyl chlorides but not the (phenyl)diazoacetaldehydes even al temperatures as low as - 60 degrees. The diazo-transfer reactions of phenylacetaldehydes and 2-azido-1-ethylpyridin-1-ium tetrafluoroborate also did not yield the expected(pheny)diazoacetaldehydes.