Advantageous Syntheses of Diazo Compounds by Oxidation of Hydrazones with Lead Tetraacetate in Basic Environments
作者:Terrence L. Holton、Harold Schechter
DOI:10.1021/jo00120a013
日期:1995.7
Varied sensitive diazo compounds 3 are produced efficiently and safely in 3-6 g quantities by oxidation (eq 1) of hydrazones 1 at -78 degrees C with lead tetraacetate (2) in triethylamine/chloroform, N-methylmorpholine/dimethylformamide, tetramethylguanidine (8)/dimethylformamide, and tetramethylguanidine/methylene chloride, respectively, upon use of appropriate workup and handling techniques. New and improved nonhazardous procedures have been developed for preparing and handling hydrazones 1 from aldehydes and ketones in reactions with excess hydrazine.
Ensslin,H.M.; Hanack,M., Angewandte Chemie, 1967, vol. 79, p. 687
作者:Ensslin,H.M.、Hanack,M.
DOI:——
日期:——
Synthesis of Acyclic Ketones by Catalytic, Bidirectional Homologation of Formaldehyde with Nonstabilized Diazoalkanes. Application of a Chiral Diazomethyl(pyrrolidine) in Total Syntheses of Erythroxylon Alkaloids
作者:Andrew J. Wommack、Jason S. Kingsbury
DOI:10.1021/jo401377a
日期:2013.11.1
This work offers a catalytic approach to convergent ketone assembly based upon formal and tandem C–H insertion of diazoalkanes in the presence of limiting amounts of monomeric formaldehyde, which is easily generated as a gas by thermolysis of the inexpensive and abundant paraformaldehyde (∼30 USD/kg). The method forms di-, tri-, and even tetrasubstituted acetones with high efficiency, and it has streamlined