Azetidine-derived dinuclear zinc catalyzed asymmetric phospha-Michael addition of dialkyl phosphite to α,β-unsaturated carbonyl compounds

Abstract

The asymmetric phospha-Michael addition of dialkyl phosphite to α,β-unsaturated carbonyl compounds by using an azetidine-derived dinuclear zinc catalyst was described. The catalyst was proved to be general and efficient for a broad spectrum of enones and α,β-unsaturated N-acylpyrroles. A series of phosphonate-containing compounds were generated with excellent enantioselectivities (up to 99% ee) and chemical yields (up to 99%) under mild conditions without using additives. The products were obtained with more than 95% ee for 23 examples of α,β-unsaturated carbonyl compounds. A positive nonlinear effect was observed and the possible mechanism was proposed.

Promiscuous Lipase-Catalyzed Markovnikov Addition of H-Phosphites to Vinyl Esters for the Synthesis of Cytotoxic α-Acyloxy Phosphonate Derivatives

“…Carboxylic acids can be also used as an acylating agents for α-hydroxy phosphonates supported by coupling reagents e.g., N , N ′-dicyclohexylcarbodiimide and 4-dimethylaminopyridineas as the base [ 31 ]. Apart from Michaelis–Arbuzov and Michaelis–Becker reactions, the phosphorus–carbon bond is formed using phospha-Michael addition under basic conditions [ 32 , 33 , 34 , 35 , 36 , 37 ]. Therefore, the possibility of using this approach in the synthesis of bioactive α-acyloxy phosphonates should be considered.…”

Dinuclear Metal‐ProPhenol Catalysts: Development and Synthetic Applications

“…In 2017, the same group disclosed an analogous phospha-Michael reaction of diethyl phosphite 177 with b-monosubstituted a,b-unsaturated carbonyl compounds 178 (Scheme 45 b). [84] The catalyst derived from L-2 a proved to be effective for a vast array of Michael acceptors, offering phosphonate-containing adducts 179 in up to 99 % yield and 99 % ee. A positive non-linear effect was also observed, suggesting that the dimeric form of the Zn-catalyst may be involved in the catalytic cycle.…”

“…In 2017, the same group disclosed an analogous phospha‐Michael reaction of diethyl phosphite 177 with β‐monosubstituted α,β‐unsaturated carbonyl compounds 178 (Scheme b) . The catalyst derived from L‐2 a proved to be effective for a vast array of Michael acceptors, offering phosphonate‐containing adducts 179 in up to 99 % yield and 99 % ee .…”

Zweikernige Metall‐ProPhenol‐Katalysatoren: Entwicklung und Anwendungen in der Synthese

“…Im Jahr 2017 hat dieselbe Gruppe über eine analoge Phospha‐Michael‐Reaktion von Diethylphosphit 177 mit β‐monosubstituierten α,β‐ungesättigten Carbonylverbindungen 178 berichtet (Schema b) . Der auf L‐2 a basierende Katalysator war für ein breites Spektrum an Michael‐Akzeptoren wirksam und führte zu Phosphonat‐haltigen Addukten 179 mit bis zu 99 % Ausbeute und 99 % ee .…”