Asymmetric Synthesis of α,β‐Diaminophosphonic Acid Derivatives with a Catalytic Enantioselective Mannich Reaction

Abstract

Optically active a,b-diaminophosphonic acid derivatives were obtained from the catalytic enantioselective Mannich reaction of phosphoglycine Schiff bases with N-Boc-imines, generated in situ from a-amido sulfones.

Neue Entwicklungen bei asymmetrischen Phasentransferreaktionen

“…Die Umsetzung mit dem Katalysator 2 k lieferte a,b-Diaminophosphonsäurederivate wie 148 mit guten Enantioselektivitäten (Schema 90). [114] Bernardi [115] und Palomo [116] berichteten unabhängig voneinander über phasentransferkatalysierte Aza-HenryReaktionen aromatischer und aliphatischer Imine, die aus aAmidosulfonen in situ als reaktive N-Carbamoylimine er- and 1 m [118] in der Reaktion verwendet und ergaben die Produkte mit hohen Enantioselektivitäten (Schema 91).…”

“…[113] 4. Mannich-Reaktion [114] Bernardi [115] und Palomo [116] berichteten unabhängig voneinander über phasentransferkatalysierte Aza-Henry-Reaktionen aromatischer und aliphatischer Imine, die aus a-Amidosulfonen in situ als reaktive N-Carbamoylimine er- halten wurden (Schema 91). Die ungeschützte Hydroxygruppe des N-Benzylchininiumchlorids 2 l war ausschlaggebend für den Erhalt hoher Enantioselektivitäten.…”

Phase‐Transfer‐Catalyzed Asymmetric Michael Addition of (Iminomethyl)phosphonates to α,β‐Unsaturated Ketones: Access to α‐Aminophosphonic Acid Derivatives

“…Subsequently, Jászay's group disclosed a catalytic asymmetric Michael addition of (iminomethyl)phosphonates to acrylates and acrylonitrile in the presence of α,α,α,α‐tetraaryl‐1,3‐dioxolane‐4,5‐dimethanol (TADDOL) derivatives and chiral crown ethers to give products with moderate enantioselectivities (Scheme b) . Bernardi and co‐workers disclosed a phase‐transfer‐catalyzed asymmetric Mannich reaction of (iminomethyl)phosphonates and α‐amidosulfones (Scheme c) . Recently, our group developed a phase‐transfer‐catalyzed asymmetric Michael addition of diethyl (iminomethyl)phosphonates to α,β‐unsaturated ketones.…”

“…In the presence of 1 mol-% of a chiral dinuclear Nspiro ammonium salt, the addition reaction proceeded [a] Bernardi and co-workers disclosed a phase-transfer-catalyzed asymmetric Mannich reaction of (iminomethyl)phosphonates and α-amidosulfones (Scheme 1c). [6] Recently, our group developed a phase-transfer-catalyzed asymmetric Michael addition of diethyl (iminomethyl)phosphonates to α, -unsaturated ketones.In the presence of a chiral BINOL-derived (BINOL = 1,1′-bi-2naphthol) N-spiro ammonium salt as a phase-transfer catalyst, [7] the reaction proceeded well to give addition products with high diastereoselectivities and moderate to good enantioselectivities. Furthermore, the corresponding adducts could be readily converted into the corresponding cyclic α-aminophosphonic acid derivatives, which contain three stereocenters (Scheme 1d).…”

“…In the presence of 1 mol-% of a chiral dinuclear Nspiro ammonium salt, the addition reaction proceeded [a] Bernardi and co-workers disclosed a phase-transfer-catalyzed asymmetric Mannich reaction of (iminomethyl)phosphonates and α-amidosulfones (Scheme 1c). [6] Recently, our group developed a phase-transfer-catalyzed asymmetric Michael addition of diethyl (iminomethyl)phosphonates to α, -unsaturated ketones.…”