Optically active bis (oxazolinyl) phenyl (Phebox) was designed as an anionic N-C-N pincer ligand, and (Phebox) SnMe
3 was prepared as its stable precursor. The aqua complexes, (Phebox) Rh
IIIX
2H
2O) [X=Cl, Br, F], [(Phebox) M
II (H
2O)] (BF
4) [M=Pd, Pt] and [(Phebox) Pt
IV (H
2O)] (BF
4), were synthesized by the oxidative addition or transmetallation of Rh
I, Pd
II and Pt
II precursors with (Phebox) SnMe
3 and subsequent ligand exchange reaction. X-ray structure studies revealed that the octahedral structure of Rh
III complex is isosteric with the Pt
IV, and the Pd
II and Pt
II complexes are almost the same configuration with a square-planar structure. These aqua complexes acted as efficient catalysts for enantioselective allylation of aldehydes with allyltin reagents, hetero Diels-Alder reaction of Danishefsky's diene with glyoxylates and the aldol-type condensation of tosylmethyl isocyanide with aldehydes. While (Phebox) Rh
III (SnMe
3) Cl complexes catalyzed the Michael addition of α-cyanopropionates to acrolein.
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