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A family of tunable precatalysts [Pd((S)-L*)(NCMe) 2 ](OTf) 2 , where L* is 4,4'-disubstituted BINAP or SEGPHOS, was synthesized and used for the asymmetric intermolecular hydroamination of aniline to vinylarenes with ee values of up to 85%, and it is believed that the bulky groups on the 4,4'-positions and the narrower dihedral angle of the biaryl moiety are responsible for the ee enhancement in these reactions.

The enantiomerically pure bridged aminotroponiminate S,S-H2{(iPrATI)2diph}, in which two amino-isopropyl-troponimine moieties are linked by 1,2-(S,S)-diamino-1,2-diphenylethane, has been prepared. The chiral lutetium alkyl complex of composition [(R,R)-{(iPrATI)2diphLuCH2SiMe3(THF)] (3) was obtained via two synthetic approaches. In the first approach the dipotassium salt [(S,S)-K2{(iPrATI)2diph}] (1) of the ligand was reacted via a salt metathesis with lutetium trichloride to give [(S,S)-{(iPrATI)2diph}LuCl(THF)] (2). Reaction of 2 with LiCH2SiMe3 resulted in 3. Compound 3 can also be obtained by the reaction of [Lu(CH2SiMe3)3(THF)2] with (S,S)-H2{(iPrATI)2diph} under elimination of Me4Si. The alkyl complex 3 was used as catalyst in the intramolecular hydroamination reaction of nonactivated terminal aminoolefins. Good catalytic activities and moderate enantioselectivties were observed.

A conceptually novel approach for asymmetric intramolecular hydroamination, hydroalkoxylation and hydrocarbonation of alkynes using chiral palladium catalysts are described. The reactions of the aminoalkynes 5, alkynols 7, and alkynylmethines 9 in the presence of Pd2(dba)3 x CHCl3/PhCOOH/renorphos 4 in benzene (or benzene-hexane) at 100 degrees C gave the corresponding cyclization products (nitrogen heterocycles 6, oxygen heterocycles 8, and carbocycles 10) in good yields with good enantioselectivities. The origins of enantioselectivities in the hydroamination reaction are discussed based on DFT computations.

The synthesis of the ligand precursor 1,3-bis{(R)-1-[(S)-2-(diphenylphosphanyl)ferrocenyl]ethyl}imidazolium iodide ([PCPH]I, 1) was extended to the electronically and sterically modified ligand precursors 1,3-bis{(R)-1-[(S)-2-{[3,5-bis(trifluoromethyl)phenyl]phosphanyl}ferrocenyl]ethyl}imidazolium iodide ([3,5-CF3-PCPH]I, 6), and 1,3-bis[(R)-1-{(S)-2-[bis(3,5-dimethylphenyl)phosphanyl]ferrocenyl}ethyl]imidazolium iodide ([3,5-Me-PCPH]I, 7). Palladium complexes were prepared starting from [Pd(OAc)2]3 in THF to afford [PdI(PCP)]OAc (8), [Pd(OAc)(3,5-CF3-PCP)]I (9), and [PdI(3,5-Me-PCP)]OAc (10), in excellent yields. The crystal structures of the ligand precursor [3,5-CF3-PCPH]I (6), the complex [PdI(3,5-CF3-PCP)]PF6 (14), as well as the dicationic complex [Pd(NCCH3)(PCP)](PF6)2 (11), were determined by X-ray diffraction. Complex 11 and its derivative [Pd(NCCH3)(3,5-Me-PCP)](PF6)2 (13) have been tested as catalysts in the asymmetric addition of, for example, thiomorpholine tomethacrylonitrile giving selectivities up to 63 and 75 % ee, respectively, at –80 °C. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

The Pd-catalyzed reaction of internal alkynes with tethered amino groups in the presence of PhCO2H and RENORPHOS as chiral phosphine ligand is reported. Various five- and six-membered nitrogen-containing heterocycles were obtained in good to high yield with moderate to high ee.

A set of catalytic, intermolecular hydroaminations of strained bicyclic olefins and dienes are reported that occur in both high yield and high enantioselectivity. These reactions occur with a catalyst generated from [Ir(cyclooctene)Cl]2, sterically hindered and electron-rich derivatives of the Segphos and BIPHEP family of ligands, and a soluble base. This system catalyzes the addition of various anilines to norbornene, norbornadiene, and other bicyclic olefins. The products from addition of p-anisidine can be transformed to BOC-protected norbornylamine and to substituted cyclopentanes in nearly enantiopure form. Mechanistic studies show that addition of aniline-d2 occurs in a syn fashion and suggest that the catalytic cycle comprises oxidative addition of aniline to form a bis-anilide hydride complex, followed by migratory insertion of olefin and reductive elimination of product in a series of steps involving iridium complexes containing ancillary bisphosphine and arylamide ligands.