Catalytic asymmetric hydrogenation of α-ketoesters and quinoline using electronically enriched BINAP

Electronically enriched chiral BINAP derivatives were synthesized incorporating electron-donating substituents at the para-phenyl position and evaluated for the Ru-catalyzed homogeneous asymmetric hydrogenation of α-ketoesters with up to 92% ee. These diphophosphines were also excellent ligands for the iridium-catalyzed asymmetric hydrogenation of quinolines.

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(R)-6,6′-Didodecyl-2,2′-bis[bis(4-methoxyphenyl)phosphino]1,1′binaphthylC72H88O4P2Ee = 99%[α]D25=-25.65 (c 0.64, CHCl)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-6,6′-Didodecyl-2,2′-bis[bis(4-hydroxyphenyl)phosphino]1,1′-binaphthylC68H80O4P2Ee = 99%[α]D25=+42.0 (c 0.83, CH2Cl2)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-2,2′-Bis[bis(4-hydroxyphenyl)phosphino]1,1′-binaphthylC44H32O4P2Ee = 99%[α]D25=+29 (c 0.9, MeOH)Source of chirality: asymmetric synthesisAbsolute configuration: (R)

(R)-2,2′-Bis[bis(4-methoxyphenyl)phosphino]1,1′-binaphthylC48H40O4P2Ee = 99%[α]D25=+107.6 (c 0.04, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (R)