Chiral ligand

#The present invention relates to a chiral transition metal complex, which is useful as a catalyst for converting a prochiral unsaturated organic compound to a corresponding asymmetric compound, and a process for producing the same.

#Martins et al. discloses an optically active transition metal complex catalyst having an aminophosphine-phosphinite ligand (Synlett., 1998, Vol. 10, pp1162), however, the catalyst was not always satisfactory in the asymmetric reaction of converting a carbonyl compound to a chiral alcohol compound.

#Hence, a more effective catalyst that can be suitably used for industrial-scale production has been desired.

#Hereinafter, this invention is described in more detail by reference the Examples, which however are not intended to limit this invention.

#10.0 g (45.6 mmol) of ethyl (S,S)-2-(N-α-methylbenzyl)azetidine-carboxylate was dissolved in 100 ml diethyl ether under an argon atmosphere, and 46 ml (137 mmol) of 3 M methyl magnesium bromide in ethyl ether was added dropwise thereto. After completion of the addition, the mixture was stirred for 2 hours under reflux. To the reaction mixture obtained after cooling was added 200 ml aqueous saturated ammonium chloride, and the aqueous water was extracted with diethyl ether, and the resultant organic layer was washed succively with water and aqueous saturated saline and then dried over anhydrous sodium sulfate. is organic layer was concentrated to give 9.24 g (S)-α,α-dimethyl-2-(N-α-methylbenzyl)azetidine-methanol (yield 92%) as yellow oil.

#4.0 g (18.2 mmol) of (S,S)-α,α-dimethyl-2-(N-α-methylbenzyl)-azetidine-methanol thus obtained was dissolved in a mixed solvent of 100 of methanol, 10 ml of water and 2 ml of acetic acid, then 350 mg of adium hydroxide supported on activated carbon was added, and the mixture was reacted at room temperature for 10 hours in a hydrogen eam. The resultant reaction mixture was filtered through Celite, then filtrate of reaction mixture was concentrated under reduced pressure, and the resultant residues were dissolved in 50 ml of 1 N hydrochloric acid washed with diethyl ether. After washing, the residues was contacted h aqueous sodium hydroxide and extracted twice with 30 ml chloroform, d the resultant organic layer was washed with water and saturated aqueous saline, dried over anhydrous sodium sulfate and concentrated to ve 1.55 g of (S)-α,α-dimethyl-2-azetidine-methanol (yield 74%) as a white solid. The melting point was 49 to 50° C.