Synthesis of phosphorylated sulfoximines and sulfinamides and their application as ligands in asymmetric metal catalysis

Starting from inexpensive materials and following simple protocols various N-phosphorylated sulfoximines and sulfinamides have been synthesized. The newly prepared compounds were then applied as chiral ligands in asymmetric transition metal catalysis. Phosphorus triamide-type ligands derived from (S)-glutamic acid were found to be the most efficient stereoselectors in enantioselective palladium-catalyzed allylic substitutions (up to 97% ee). On the other hand, diamidophosphite-type structures stemming from (S)-proline were the best ligands in rhodium-catalyzed hydrogenation reactions (up to 84% ee).

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(2R,2′R,5S)-2-(S-Methyl-S-phenylsulfonimidoyl)-3-phenyl-1,3-diaza-2-phosphabicyclo[3.3.0]-octaneC18H22N3OPSDe = 82%[α]D22=-219.2 (c 1.0, CHCl3)Source of chirality: (S)-glutamic acid(R)-S-Methyl-S-phenylsulfoximineAbsolute configuration: (2R,2′R,5S)

(2R,2′S,5S)-2-(S-Methyl-S-phenylsulfonimidoyl)-3-phenyl-1,3-diaza-2-phosphabicyclo[3.3.0]-octaneC18H22N3OPSDe = 100%[α]D22=-14.4 (c 1.0, CHCl3)Source of chirality: (S)-glutamic acidS-S-Methyl-S-phenylsulfoximineAbsolute configuration: (2R,2′S,5S)

(2R,5S)-2-S,S-Diphenylsulfonimidoyl)-3-phenyl-1,3-diaza-2-phosphabicyclo[3.3.0]-octaneC23H24N3OPSDe = 67%[α]D22=-151.6 (c 1.0, CHCl3)Source of chirality: (S)-glutamic acidAbsolute configuration: (2R,5S)

(2S,2′R,5S)-2-(S-Methyl-S-phenylsulfonimidoyl)-3,1,2-oxazaphosphabicyclo[3.3.0]-octaneC12H17N2O2PSDe = 70%[α]D22=+95.8 (c 1.0, CHCl3)Source of chirality: (S)-proline(R)-S-Methyl-S-phenylsulfoximineAbsolute configuration: (2S,2′R,5S)

(2S,2′S,5S)-2-(S-Methyl-S-phenylsulfonimidoyl)-3,1,2-oxazaphosphabicyclo[3.3.0]-octaneC12H17N2O2PSDe = 84%[α]D22=+128.0 (c 1.0, CHCl3)Source of chirality: (S)-proline(S)-S-Methyl-S-phenylsulfoximineAbsolute configuration: (2S,2′S,5S)

(2S,5S)-2-S,S-Diphenylsulfonimidoyl)-3,1,2-oxazaphosphabicyclo[3.3.0]-octaneC17H19N2O2PSDe = 80%[α]D22=+57.5 (c 1.0, CHCl3)Source of chirality: (S)-prolineAbsolute configuration: (2S,5S)

(2S,2′S,5S)-2-(N-Benzyl-S-tert-butylsulfinamidoyl)-3,1,2-oxazaphosphabicyclo[3.3.0]-octaneC16H25N2O2PSDe = 90%[α]D22=+234.2 (c 1.0, CHCl3)Source of chirality: (S)-proline(S)-N-Benzyl-2-methylpropane-2-sulfinamideAbsolute configuration: (2S,2′S,5S)

(2S,2′R,5S)-2-(N-Benzyl-S-tert-butylsulfinamidoyl)-3,1,2-oxazaphosphabicyclo[3.3.0]-octaneC16H25N2O2PSDe = 84%[α]D22=-43.1 (c 1.0, CHCl3)Source of chirality: (S)-proline(R)-N-Benzyl-2-methylpropane-2-sulfinamideAbsolute configuration: (2S,2′R,5S)