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The three diastereomers of (JZ^t)-2,3-0-isopropylidene-2,3-dihydroxy-l,4-bis([2-methoxyphenyl]phenylphosphino)butane (1) and of (fJ^?)-2,3-0-isopropylidene-2,3-dihydroxy-l,4-bis ([2-(dimethylammo)phenyl]phenylphosphino)butane (2) have been prepared and isolated. Advanced intermediates in the preparation and isolation of diastereomers of (fi^Z)-2,3-0-isopropylidene-2,3-dihydroxy-l,4-bis ([2,6dimethoxyphenyl]phenylphosphino)butane (3) are also described. Absolute configurations of four of the chiral phosphine ligands were determined via single-crystal X-ray diffraction studies of molybdenum tetracarbonyl derivatives ((RPJ1P)•6, (RPJlP)-7, (RPJ1P)-S, and (SP,SP)-8); this facilitated assignments of absolute configurations for all the isomers of ligands 1-3. These bisphosphine ligands are rare insofar as they have chiral phosphorus centers supported on an asymmetric carbon framework. Several reactions were performed to test for "cooperativity" between chiral centers in these ligands with respect to asymmetric induction in transition-metal-catalyzed processes. Matching and mismatching effects were observed, but there are some irregular trends in the data. The enantioselectivities obtained were moderate but greater than that for the parent ligand DIOP in some cases. The o-dimethylamino functionality of ligands 2 may play an active role in the coordination of these isomeric bisphosphine ligands. Trends and factors influencing the performance of ligands 1-3 in asymmetric catalysis are discussed. Crystal data for the compounds analyzed via X-ray diffraction are as follows. (RPJlP)•6: monoclinic, space group 2 (No. 4), o = 11.621

1027were collected on a Rigaku AFC5S single-crystal, automated four-circle diffractometer using Mo K a radiation. The cell was determined to be C-centered monoclinic following data reduction of the primitive triclinic unit cell, obtained from a least-squares fit of 22 random reflections. Crystal symmetry was confirmed by the Laue symmetry check. Intensity statistics and systematic absences indicated crystalline in the acentric spacegroup Cc (no 91, which was confirmed by successful refinement of the structure. The structure was solved with SHELXSW followed by successive least-squares full-matrix difference refinements (TEXSAN v. 2.0)@ to convergence with R = 0.063 and R, = 0.068. The fluorine and oxygen atoms were refined anisotropically to convergence; carbon (63) Sheldrick, G. M. (1986). SHELX. (64) Molecular Structure Coorporatiion. TEXASN (2.0), Program for Crystal Structure Determination and Refinement; The Woodlands, TX. Cromer, D. T.; Waber, J. T. International Tables for X-Ray Crystallography; Kynoch Press: Birmingham, 1974; Vol. IV, p 71 (scattering factors), p 148 (anamalous dispersion) (current distributor: Kluwer Academic Publishers, Dordrecht).atoms were refined with isotropic thermal parameters. The hydrogen atoms were included in calculated positions but were not refined. Equivalent reflections were averaged, and the data were corrected for Lp effects and anomalous dispersion. Corrections for decay and absorption were not applied. Acknowledgment.Racemic, and optically active, 2-methyl-3-(N-tosylamino)alkenes I were prepared and subjected to both catalyzed and uncatalyzed hydroborations. Data obtained for the catalyzed hydroborations of these allylamine derivatives are consistent with the theory of secondary orbital interactions in transition metal mediated processes presented in the preceding paper. Surprisingly, diastereoselectivities for conventional (uncatalyzed) hydroborations of the same substrates can be extremely sensitive to the borane used; anti products result when boranetetrahydrofuran complex is reacted with substrates I (R' = Bn), while with 9-BBN (9-borabicyclo[3.3.1]nonane) these reactions are syn selective. Some of these results are contrary to expectations based upon experimental and theoretical data in the current literature for hydroboration of allylic alcohols. Methodology described in this paper facilitates syntheses of amine alcohols I1 with extremely high syn and anti selectivities. (1) Roa, A. V. R.; Gurjar, M. K.; Khare, V. B.; Ashok, B.; Deshmukh, M. N. Tetrahedron Lett. 1990, 31, 271.Lack of activity in this area is unfortunate because it encompasses preparations of chiral amino alcohols, valuable starting materials for syntheses of new amino acid analogues, @-lactams, and other substances of pharmaceutical Syntheses of Allylamine Derivatives 2-15. This study focuses upon N-tosyl-protected allylamine derivatives, principally because absolute stereochemistry at enolizable centers can be preserved when proximal TsNH protons are removed preferentially.+" However, there are o...