| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1347428 | Tetrahedron: Asymmetry | 2009 | 6 Pages |
Reaction of the (S,S)-salen-cobalt(III)-N-benzyl-l-serine complex 2 with four diol-derived chlorophosphites afforded phosphites 3a–3d in moderate yields (37–72%). Structural studies of these monodentate phosphite ligands and of their Rh-complexes were performed in solution by 1H and 31P NMR spectroscopy. The ligands were screened in several enantioselective catalytic applications, showing good activity and moderate enantioselectivity in the palladium-catalyzed desymmetrization of meso-cyclopenten-2-ene-1,4-diol biscarbamate.
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(S,S)-N,N′-Bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminocobalt(III) (S)-N-Benzyl Serinate-biphenyl-2,2′-diol-phosphiteC58H71CoN3O7P[α]D23=-681.8 (c 0.094, CHCl3)Source of chirality: (1S,2S)-cyclohexane-1,2-diamine; (S)-2-(benzylamino)-3-hydroxypropanoic acid (N-benzyl-l-serine)Absolute configuration: (S,S,S)
(S,S)-N,N′-Bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminocobalt(III) (S)-N-benzyl serinate-3,3′,5,5′-tetramethylbiphenyl-2,2′-diol-phosphiteC62H79CoN3O7P[α]D23=-1050.8 (c 0.077, CHCl3)Source of chirality: (1S,2S)-cyclohexane-1,2-diamine; (S)-2-(benzylamino)-3-hydroxypropanoic acid (N-benzyl-l-serine)Absolute configuration: (S,S,S)
(S,S)-N,N′-Bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminocobalt(III) (S)-N-benzyl serinate-(Sa)-1,1′-binaphthyl-2,2′-diol-phosphiteC66H75CoN3O7P[α]D22=-775.2 (c 0.078, CHCl3)Source of chirality: (1S,2S)-cyclohexane-1,2-diamine; (S)-2-(benzylamino)-3-hydroxypropanoic acid (N-benzyl-l-serine) and (Sa)-1,1′-binaphthyl-2,2′-diolAbsolute configuration: (S,S,S,Sa)
(S,S)-N,N′-Bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminocobalt(III) (S)-N-benzyl serinate-(Ra)-1,1′-binaphthyl-2,2′-diol-phosphiteC66H75CoN3O7P[α]D23=-1227.3 (c 0.055, CHCl3)Source of chirality: (1S,2S)-cyclohexane-1,2-diamine; (S)-2-(benzylamino)-3-hydroxypropanoic acid (N-benzyl-l-serine), and (Ra)-1,1′-binaphthyl-2,2′-diolAbsolute configuration: (S,S,S,Ra)
