A series of novel chiral diphosphite ligands have been synthesized from d-mannitol derivatives and chlorophosphoric acid diary ester, and were successfully employed in the copper catalyzed enantioselective conjugate addition of organozinc reagents diethylzinc and dimethylzinc to cyclic and acyclic enones. The stereochemically matched combination of d-mannitol and (R)-H8-binaphthyl in ligand 1,2:5,6-di-O-isopropylidene-3,4-bis[(R)-1,1′-H8-binaphthyl-2,2′-diyl] phosphite-d-mannitol was essential to afford 93% ee for 3-ethylcyclohexanone, 92% ee for 3-ethylcyclopentanone, and 90% ee for 3-ethylcycloheptanone in toluene, using Cu(OTf)2 as a catalytic precursor. The results clearly indicated that the chiral organocopper reagent exhibited high enantioselectivies for cyclic enones bearing different ring sizes. As for the backbone of this type of ligand, it has been demonstrated that 1,2:5,6-di-O-isopropylidene-d-mannitol was more efficient than 1,2:5,6-di-O-cyclohexylidene-d-mannitol. The sense of the enantiodiscrimination was mainly determined by the configuration of the diaryl phosphite moieties in the 1,4-addition of cyclic enones.1,2:5,6-Di-O-cyclohexylidene-3,4-bis[(R)-1,1′-H8-binaphthyl-2,2′-diyl]phosphite-d-mannitolC58H68O10P2[α]D20=-165 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and H8-BINOLAbsolute configuration: (2R,3R,4R,5R,Ra,Ra)1,2:5,6-Di-O-cyclohexylidene-3,4-bis[(S)-1,1′-H8-binaphthyl-2,2′-diyl]phosphite-d-mannitolC58H68O10P2[α]D20=+184 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and H8-BINOLAbsolute configuration: (2R,3R,4R,5R,Sa,Sa)1,2:5,6-Di-O-isopropylidene-3,4-bis[(R)-1,1′-binaphthyl-2,2′-diyl]phosphite-d-mannitolC52H44O10P2[α]D20=-309 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and BINOLAbsolute configuration: (2R,3R,4R,5R,Ra,Ra)1,2:5,6-Di-O-isopropylidene-3,4-bis[(S)-1,1′-binaphthyl-2,2′-diyl]phosphite-d-mannitolC52H44O10P2[α]D20=+496 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and BINOLAbsolute configuration: (2R,3R,4R,5R,Sa,Sa)1,2:5,6-Di-O-isopropylidene-3,4-bis[(R)-1,1′-H8-binaphthyl-2,2′-diyl]phosphite-d-mannitolC52H60O10P2[α]D20=-205 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and H8-BINOLAbsolute configuration: (2R,3R,4R,5R,Ra,Ra)1,2:5,6-Di-O-isopropylidene-3,4-bis[(S)-1,1′-H8-binaphthyl-2,2′-diyl]phosphite-d-mannitolC52H60O10P2[α]D20=+213 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and H8-BINOLAbsolute configuration: (2R,3R,4R,5R,Sa,Sa)

A novel catalytic system for the hydrogenation of dimethyl itaconate has been developed by using rhodium–diphosphite complexes. These chiral diphosphite ligands were derived from glucopyranoside, d-mannitol derivatives, and binaphthyl or H8-binaphthyl phosphochloridites. The ligands based on the methyl 3,6-anhydro-α-d-glucopyranoside backbone and (R)- and (S)-binaphthol and/or (R)- and (S)-2,2′-dihydroxy-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthol gave almost complete conversion of the dimethyl itaconate and both enantiomers of dimethyl 2-methylsuccinate with excellent enantioselectivities. The stereochemically matched combination of methyl 3,6-anhydro-α-d-glucopyranoside and H8-(S)-binaphthyl in ligand 2,4-bis{[(S)-1,1′-H8-binaphthyl-2,2′-diyl]-phosphite} methyl 3,6-anhydro-α-d-glucopyranoside was essential to afford dimethyl 2-methylsuccinate with up to 98% ee. The sense of the enantioselectivity of products was predominantly determined by the configuration of the biaryl moieties of the ligands. An initial screening of [Rh(cod)2]BF4 with these ligands in the hydrogenation of (E)-2-(3-butoxy-4-methoxybenzylidene)-3-methylbutanoic acid was carried out. Good enantioselectivity (75% ee) and low yield for (R)-2-(3-butoxy-4-methoxybenzyl)-3-methylbutanoic acid were obtained.2,4-Bis{[(R)-1,1′-binaphthyl-2,2′-diyl] phosphite}-methyl 3,6-anhydro-α-d-glucopyranosideC47H34O9P2[α]D20=-321 (c 0.2, CH2Cl2)Source of chirality: d-glucose H8− BINOLAbsolute configuration: (1S,2R,3S,4R,5R,Ra,Ra)2,4-Bis{[(S)-1,1′-binaphthyl-2,2′-diyl] phosphite}-methyl 3,6-anhydro-α-d-glucopyranosideC47H34O9P2[α]D20=+502 (c 0.2, CH2Cl2)Source of chirality: D-glucose and BINOLAbsolute configuration: (1S,2R,3S,4R,5R,Sa,Sa)2,4-Bis{[(R)-1,1′-H8-binaphthyl-2,2′-diyl] phosphite}-methyl 3,6-anhydro-α-d-glucopyranosideC47H50O9P2[α]D20=-126 (c 0.2, CH2Cl2)Source of chirality: d-glucose and H8-BINOLAbsolute configuration: (1S, 2R, 3S, 4R, 5R, Ra, Ra)2,4-Bis{[(S)-1,1′-H8-binaphthyl-2,2′-diyl] phosphite}-methyl 3,6-anhydro-α-d-glucopyranosideC47H50O9P2[α]D20=+309 (c 0.2, CH2Cl2)Source of chirality: d-glucose and H8-BINOLAbsolute configuration: (1S,2R,3S,4R,5R,Sa,Sa)2,4-Bis{[(R)-1,1′-binaphthyl-2,2′-diyl] phosphite}-phenyl 3,6-anhydro-β-d-glucopyranosideC52H36O9P2[α]D20=-451 (c 0.2, CH2Cl2)Source of chirality: d-glucose and BINOLAbsolute configuration: (1S,2R,3S,4R,5R,Ra,Ra)2,4-Bis{[(S)-1,1′-binaphthyl-2,2′-diyl] phosphite}-phenyl 3,6-anhydro-β-d-glucopyranosideC52H36O9P2[α]D20=+417 (c 0.2, CH2Cl2)Source of chirality: d-glucose and BINOLAbsolute configuration: (1S,2R,3S,4R,5R,Sa,Sa)2,4-Bis{[(R)-1,1′-H8-binaphthyl-2,2′-diyl] phosphite}-phenyl 3,6-anhydro-β-d-glucopyranosideC52H52O9P2[α]D20=-255 (c 0.4, CH2Cl2)Source of chirality: d-glucose and H8-BINOLAbsolute configuration: (1S,2R,3S,4R,5R,Ra,Ra)2,4-Bis{[(S)-1,1′-H8-binaphthyl-2,2′-diyl] phosphite}-phenyl 3,6-anhydro-β-d-glucopyranosideC52H52O9P2[α]D20=+230 (c 0.4, CH2Cl2)Source of chirality: d-glucose and H8-BINOLAbsolute configuration: (1S,2R,3S,4R,5R,Sa,Sa)C58H52O10P21,2:5,6-Di-O-cyclohexylidene-3,4-bis[(R)-1,1′-binaphthyl-2,2′-diyl]phosphite-d-mannitol[α]D20=-365 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and BINOLAbsolute configuration: (2R,3R,4R,5R,Ra,Ra)1,2:5,6-Di-O-cyclohexylidene-3,4-bis[(S)-1,1′-binaphthyl-2,2′-diyl]phosphite-d-mannitolC58H52O10P2[α]D20=+437 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and BINOLAbsolute configuration: (2R,3R,4R,5R,Sa,Sa)1,2:5,6-Di-O-cyclohexylidene-3,4-bis[(R)-1,1′-H8-binaphthyl-2,2′-diyl]phosphite-d-mannitolC58H68O10P2[α]D20=-165 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and H8-BINOLAbsolute configuration: (2R,3R,4R,5R,Ra,Ra)1,2:5,6-Di-O-cyclohexylidene-3,4-bis[(S)-1,1′-H8-binaphthyl-2,2′-diyl]phosphite-d-mannitolC58H68O10P2[α]D20=+184 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and H8-BINOLAbsolute configuration: (2R,3R,4R,5R,Sa,Sa)1,2:5,6-Di-O-isopropylidene-3,4-bis[(R)-1,1′-binaphthyl-2,2′-diyl]phosphite-d-mannitolC52H44O10P2[α]D20=-309 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and BINOLAbsolute configuration: (2R,3R,4R,5R,Ra,Ra)1,2:5,6-Di-O-isopropylidene-3,4-bis[(S)-1,1′-binaphthyl-2,2′-diyl]phosphite-d-mannitolC52H44O10P2[α]D20=+496 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and BINOLAbsolute configuration: (2R,3R,4R,5R,Sa,Sa)1,2:5,6-Di-O-isopropylidene-3,4-bis[(R)-1,1′-H8-binaphthyl-2,2′-diyl]phosphite-d-mannitolC52H60O10P2[α]D20=-205 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and H8-BINOLAbsolute configuration: (2R,3R,4R,5R,Ra,Ra)1,2:5,6-Di-O-isopropylidene-3,4-bis[(S)-1,1′-H8-binaphthyl-2,2′-diyl]phosphite-d-mannitolC52H60O10P2[α]D20=+213 (c 0.2, CH2Cl2)Source of chirality: d-mannitol and H8-BINOLAbsolute configuration: (2R,3R,4R,5R,Sa,Sa)