Applications of N′-monofunctionalised TsDPEN derivatives in asymmetric catalysis

Abstract

N′-Monoalkylated or N′-mono(thio)acylated(N-sulfonyl)-1,2-diphenylethylene-1,2-diamine (TsDPEN) derivatives are have found extensive applications in asymmetric catalysis of a wide range of synthetic applications.

Probing the Effects of Heterocyclic Functionality in [(Benzene)Ru(TsDPENR)Cl] Catalysts for Asymmetric Transfer Hydrogenation

“…15,16 The use of the in situ catalysts in these cases gave products in good conversion and ees similar to those previous reported for ATH catalysis, noting that ortho-substituted acetophenone derivatives are challenging substrates that often give lower ees than less hindered ketones. [1][2][3]19 Figure 7. Products of ATH of substituted ketones using in situgenerated complexes 17-20.…”

“…2 Although the parent compounds contain a TsDPEN ligand with a primary amine bound to the Ru(II), it is known that one substituent can be added to the amine atom, i.e. in complexes 2, without causing lack of activity (Figure 1), [3][4][5][6][7][8][9][10][11][12][13] and in some cases a higher activity, notably to C=N reduction, is observed. 5,6,[11][12][13] Functional groups on the amine atom of TsDPEN can also provide a means for tuning the structures of complexes to particular substrates, 6,[11][12][13] and to modify the properties of the complexes e.g.…”

“…The [(arene)­Ru­(TsDPEN)­Cl] class of precatalyst ( 1 ) for asymmetric transfer hydrogenation (ATH) of ketones and imines, first reported by Noyori et al, are now established reagents for synthetic chemists . Although the parent compounds contain a TsDPEN ligand with a primary amine bound to the Ru­(II), it is known that one substituent can be added to the amine atom, i.e., in complexes 2 , without causing lack of activity (Figure ), − and in some cases a higher activity, notably to CN reduction, is observed. ,,− Functional groups on the amine atom of TsDPEN can also provide a means for tuning the structures of complexes to particular substrates ,− and to modify the properties of the complexes, e.g., to improve their water solubility or assist extraction from a mixture. ,, …”

Bifunctional Homogeneous Catalysts Based on Ruthenium, Rhodium and Iridium in Asymmetric Hydrogenation

“…Despite the development of other diamines, TsDPENs remain ligands of high interest because of their highly enantiodiscriminating properties, possibly tuned by the substituents on the primary amine bound to ruthenium(II). [82][83] If generally no loss of activity was observed by changing the amine substituent, in some instances beneficial effects were highlighted, such as higher activity in C=N reduction reactions [84][85][86][87] or increased water solubility. [88][89][90] Wills and co-workers reported a quite versatile series of TsDPENs in which the amine nitrogen atom was functionalized by heterocyclic residues.…”

Ruthenium-Catalyzed Highly Enantioselective Synthesis of cis-3-Quinuclidinols via DKR Asymmetric Transfer Hydrogenation

“…Asymmetric transfer hydrogenation of ketones via DKR has proved to be one of the most direct and reliable methods to produce optically active alcohols. , An ongoing interest in our laboratory is the use of chiral diamine–Ru complexes as catalysts for the construction of chiral compounds typically found in pharmaceuticals . In light of this previous work, we envisioned that the two contiguous stereogenic centers in quinuclidinol could be established in one operation via DKR-ATH.…”