Methanolysis of Dimethyl (1-Diazo-2-oxopropyl) Phosphonate: Generation of Dimethyl (Diazomethyl) Phosphonate and Reaction with Carbonyl Compounds

Diazotransfer Reactions with p-Acetamidobenzenesulfonyl Azide

A novel synthesis of the carbapen-2-em ring system

Chiral Cu(I)-bisoxazoline- and Cu(I)-PN-complexes were found to catalyze the intermolecular insertion of α-diazo compounds into N–H bonds. The insertion reactions proceed with enantioselectivities of up to 28% ee for the different α-diazo acetates into one of the N–H bonds of different amines. Analogous chiral Ag(I) complexes were found to give higher enantioselectivities of up to 48% ee, however, lower yields were obtained. There are indications, that the Ag(I)-mediated reactions follow a different reaction mechanism compared to the Cu(I)-catalyzed insertions. It is demonstrated that different α-amino acid derivatives can be obtained via this approach in good yields and with low to moderate enantioselectivities. However, the results obtained are the highest asymmetric inductions obtained for an intermolecular N–H insertion via chiral carbene complexes or chiral Lewis acid catalysis.

Cu(I)-carbenoid- and Ag(I)-Lewis acid-catalyzed asymmetric intermolecular insertion of α-diazo compounds into N–H bonds

Numerous examples illustrate the course of the thermolysis of hydrazones derived from α,β-epoxyketones and 2-phenyl- or trans-2,3-diphenyl-1-amino-aziridines. This process constitutes a preparatively useful method for the fragmentation of α,β-epoxyketones to acetylenic carbonyl compounds including acetylenic aldehydes.



Monohydrazones from phenylglyoxal and substituted N-amino-aziridines decompose smoothly and stereospecifically to the corresponding olefins and diazoacetophenone; such a process might also be useful for the preparation of other α-diazocarbonyl compounds.

α,β‐Epoxyketon → Alkinon‐Fragmentierung II: Pyrolytischer Zerfall der Hydrazone aus α,β‐Epoxyketonen und N‐Amino‐aziridinen. Über synthetische Methoden, 4. Mitteilung

Walter A. Wolf

Papers

Direct introduction of the diazo function in organic synthesis

Preparation of α-diazo carbonyl compounds