Diethyl (1-diazo-2-oxopropyl)phosphonate

CAS 21047-57-4, Cat. No EN300-19477491

Reagent for Seyferth–Gilbert homologation

Diethyl (1-Diazo-2-oxopropyl)phosphonate is primarily used in Seyferth–Gilbert homologation. It is a pale-yellow liquid, that is soluble in most organic solvents but can slowly react with alcohols^[1]. Seyferth–Gilbert homologation is one of the most common ways for the synthesis of terminal acetylenes, but besides this usage, the reagent can be used for 1,3 dipolar cycloaddition to form nitrogen heterocycles, pyrazoles, triazolines, oxazoles, and thiazoles that phosphoryl-substituted^[2]. Also, the reagent is capable in the presence of a base and carbonyl compounds to form vinylidene carbenes. In the case of aldehydes rearranging proceed to alkynes and in the case of ketones to enol ethers^{[1], [2]}.

Synonyms: Diethyl P-(1-diazo-2-oxopropyl)phosphonate; Phosphonic acid, (1-diazo-2-oxopropyl)-, diethyl ester; Phosphonic acid, (1-diazoacetonyl)-, diethyl ester; Diethyl 1-diazo-2-oxopropylphosphonate

Selected publication

1. Synthesis of Diethyl (1-Diazo-2-Oxopropyl)Phosphonate.

Varongchayakul C. Organic Syntheses 2023, 100, 84–98. DOI: 10.15227/orgsyn.100.0084

2. Diethyl (1‐Diazo‐2‐oxopropyl)Phosphonate.

Sandmeier T. Encyclopedia of Reagents for Organic Synthesis 2021, 1–2. DOI: 10.1002/047084289X.rn02416