抄録
The efficiency of catalyst molecular helicity for the asymmetrically amplified photocatalysis was investigated with newly designed ruthenium (II) complexes, M (C3) -Δ- [Ru (Menbpy) 3] 2+ (1 a ; MenbPY=4, 4'-di [(1 R, 2 S. 5 R) - (-) -menthoxycarbony1] -2, 2'-bipyridine), M (C3) -Δ or P (C3) -Λ- [Ru (R or S-PhEtbpy) 3] 2+ (2a or 2b ; R or S-PhEtbpy=4, 4'-di [(R) - (+) {or (S) - (-)} -1-phenylethylaminocarbony1] -2, 2'-bipyridine) or P (C3) -Δ- [Ru (bpy) 3] (3a), in the asymmetric resolution, synthesis, or isomerization of P (C3) -Δ and M (C3) -Λ- [Co (acac) 3] (4a and 4b ; Hacac=pentene-2, 4-dione), where P (C3) or M (C3) indicates a plus (clockwise) or minus (counterclockwise) helical arrangement along the C3 symmetry axis, respectively.
The most efficient molecular recognition in the asymmetrically amplified photocatalysis was resulted from the catalytic ability of the la helical complex possessing effective molecular extent of the helicity in the direction of C3 axis along which racemic 4a-b, reaction products [Co (acac) 2 (H2O) 2] /acac-, or five-coordinate intermediate [Co (acac) 2 (acac-)] interacted with 1a to accumulate M (C3) -4b.
The mode of asymmetric interaction between the photocatalyst and the reactant was well explained by the molecular mechanics (MM) and interactive frontier orbital (IFO) treatments.
