Diastereomeric P∗-chiral diamidophosphites with terpene fragments in asymmetric catalysis

Diamidophosphite P∗-monodentate, ligands based on terpene alcohols and (S)- or (R)-(2-anilinomethyl)pyrrolidine, induce high enantioselectivities (ee’s up to 99%) in Pd-catalyzed allylic substitution reactions. In the Pd-catalyzed deracemization of ethyl (E)-1,3-diphenylallyl carbonate up to 92% enantioselectivity has been achieved. The Rh-catalyzed asymmetric hydrogenation of α-dehydrocarboxylic acid esters leads to a maximum of 56% ee with quantitative conversion. Diastereomeric diamidophosphites prepared from [(1S)-endo]-(−)-borneol were found to be the most efficient stereoselectors.

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(2R,5S,1′S,2′R)-2-(1′,7′,7′-Trimethylbicyclo[2.2.1]heptyl-2′-oxy)-3-phenyl-1,3-diaza-2-phosphabicyclo[3.3.0]octaneC21H31N2OPEe = 100%[α]D20=-251.4 (c 1.0, CH2Cl2)Source of chirality: (S)-(+)-glutamic acidendo-(1S)-1,7,7,-trimethylbicyclo[2.2.1]heptane-2-olAbsolute configuration: (2R,5S,1′S,2′R)

(2S,5R,1′S,2′R)-2-(1′,7′,7′-Trimethylbicyclo[2.2.1]heptyl-2′-oxy)-3-phenyl-1,3-diaza-2-phosphabicyclo[3.3.0]octaneC21H31N2OPEe = 100%[α]D20=+237.7 (c 1.0, CH2Cl2)Source of chirality: (R)-(−)-glutamic acidendo-(1S)-1,7,7,-trimethylbicyclo[2.2.1]heptane-2-olAbsolute configuration: (2S,5R,1′S,2′R)

(2R,5S,1′S,2′S,5′S)-2-(2′,6′,6′-Trimethylbicyclo[3.1.1]heptan-3′-one-2′-oxy)-3-phenyl-1,3-diaza-2-phosphabicyclo[3.3.0]octaneC21H29N2O2P[α]D20=-197.1 (c 1.0, CH2Cl2)Source of chirality: (S)-(+)-glutamic acid(1S,2S,5S)-(−)-2-hydroxy-3-pinanoneAbsolute configuration: (2R,5S,1′S,2′S,5′S)

(2S,5R,1′S,2′S,5′S)-2-(2′,6′,6′-Trimethylbicyclo[3.1.1]heptan-3′-one-2′-oxy)-3-phenyl-1,3-diaza-2-phosphabicyclo[3.3.0]octaneC21H29N2O2P[α]D20=+217.4 (c 1.0, CH2Cl2)Source of chirality: (R)-(−)-glutamic acid(1S,2S,5S)-(−)-2-hydroxy-3-pinanoneAbsolute configuration: (2S,5R,1′S,2′S,5′S)