Eine effiziente und allgemeine Synthese primärer Amine durch Ruthenium‐katalysierte Aminierung sekundärer Alkohole mit Ammoniak

Abstract

Atomeffizient und selektiv führt die erste homogen katalysierte Aminierung sekundärer Alkohole mit Ammoniak zu den entsprechenden primären Aminen (siehe Schema). Die neuartige Aminierungsmethode benötigt einen kommerziell erhältlichen [Ru3(CO)12]/CataCXium PCy‐Katalysator und eine Ammoniakatmosphäre, aber keine zusätzlichen Wasserstoffquellen.

New Iridium Catalysts for the Selective Alkylation of Amines by Alcohols under Mild Conditions and for the Synthesis of Quinolines by Acceptor‐less Dehydrogenative Condensation

“…Five bases were combined with five different solvents ( Table 1, entries [1][2][3][4][5][6][7][8][9]. Diglyme and KOtBu were identified to be the best combination of solvent and base (yield 58 %; Table 1, entry 5).…”

Technische Chemie 2011

“…Biobasierte Diamine dienen als Quervernetzer für “grüne” Kunststoffe. Die effiziente Aminierung sekundärer Alkohole ist realisierbar nach dem von Vogt et al und Beller et al unabhängig voneinander entwickelten Verfahren mit Rutheniumkatalysatoren 3_13,3_14. Dieser Syntheseweg hat im Vergleich zu anderen Methoden für Amine großes Potenzial, da Alkohole zum einen gut verfügbar sind und zum anderen nur Wasser als Nebenprodukt der Reaktion entsteht.…”

Utilization of Common Ligands for the Ruthenium‐Catalyzed Amination of Alcohols

“…[8] Our group used Milsteins complex successfully for the conversion of 1,19-nonadecanediol into 1,19-nonadecanediamine. [9] Catalyst systems containing a ruthenium compound and commercially available phosphines as ligands, such as 2-(dicyclohexylphosphino)-1-phenyl-1H-pyrrole (CataCXiumPCy), [10] 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (Xantphos), [11] and 1,2-bis(dicyclohexylphosphino)ethane [12] proved to be alternatives to Milsteins catalyst (Scheme 1). The state of the art of the alcohol amination with ammonia was summarized in several review articles.…”

“…The mechanism of the alcohol amination includes an initial dehydrogenation of a primary or secondary alcohol, the reaction of the formed aldehyde or ketone with the Nnucleophile ammonia to the corresponding imine, and the final re-hydrogenation of the imine to the amine (Scheme 2). [8,[10][11][12][13][14][15][16] However, these successful catalysts and, in particular, the ligands are still quite expensive. It should be considered that the recovery of the noble metal ruthenium from the reaction residues is generally less problematic than that of the ligands, which are normally decomposed after use.…”

“…In preliminary experiments on the amination of cyclohexanol with ammonia, we tested a potential catalyst system consisting of [Ru(CO)ClHA C H T U N G T R E N N U N G (PPh 3 ) 3 ] as ruthenium precursor and (oxydi-2,1-phenylene)-bis(diphenylphosphine) (DPEphos) as ligand in tert-amyl alcohol and toluene as commonly used reaction media for aminations (Scheme 3). [8][9][10][11][12] The faster and nearly complete cyclohexanol conversion in the aromatic solvent indicated appropriate conditions for the formation of the catalyst and the target product.…”