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A series of optically active tertiary phosphorus ligands, P(OR)nPh3-n (R = bornyl, menthyl, or isopinocamphyl; n = 1, 2, or 3, 1 - 9), containing chiral alkoxy groups derived from natural terpene alcohols, menthol, borneol, and isopinocampheol, are synthesized and characterized by various spectroscopic techniques. The reactions of these ligands with iron and cobalt carbonyl complexes are carried out, giving monomeric mono- and di-substituted iron(0) and dimeric di-substituted cobalt carbonyl complexes (Fe(CO)4L, Fe(CO)3L2, and (Co(CO)3L) 2, L = 1 - 9). The characterization of these complexes by IR and NMR spectrometries is discussed. Results of preliminary studies on hydroformylation reaction under oxo conditions catalysed by several cobalt complexes are presented. Pyrazolyl bridged di-iridium(I) systems, (Ir(CO)L(mu-pz)) 2 (L = P(OMen)Ph2, usd\underline{\rm 40},usd P(OBor)Ph2, usd\underline{\rm 41}usd, and P(OMen)2Ph, usd\underline{\rm 42}),usd are prepared as diastereomers with unequal thermodynamic distribution. The X-ray crystal structure of usd\underline{\rm 41}usd shows cocrystallization of the two diastereomers in the same unit cell, which provides 1:1 kinetic distribution of the two isomers. Kinetic studies of the interconversion from the kinetic ratio to the thermodynamic ratio of the two diastereomers in usd\underline{\rm 41}usd indicates the existence of a slow inversion process of the six-membered central metallocycle in usd\underline{\rm 41}.usd Oxidative addition of MeI to usd\underline{\rm 41}usd generates a pair of diastereomeric adducts (usd\underline{\rm 43})usd in kinetic distribution, which is slowly converted to its thermodynamic distribution, implying a very slow reductive elimination of MeI. Oxidative additions of exo- and endo-norbornyl iodide to (Ir(CO)2(\mu-pz)) 2 results in same product (usd\underline{\rm 44}).usd Possible mechanisms for this process are discussed. Bisdiphenylphosphinoalkcylsilane containing chiral menthoxy group ((o-PPh2C6H4CH2)\sb2(MenO)SiH, usd\underline{\rm 47})usd is prepared and characterized. Its four-coordinate square planar platinum complex (Pt (Si(o-PPh2C6H4CH2)\sb2(OMen)) Cl, usd\underline{\rm 48})usd and five-coordinate iridium(I) complex (IrH (Si(o-PPh2C6H4CH2)\sb2(OMen)) Cl, usd\underline{\rm 49})usd are synthesized. Isomerizations of usd\underline{\rm 49}usd and its CO adducts, Ir (Si(MenO)(CH2C6H4PPh2)\sb2\rbrack(CO)HCl (usd\underline{\rm 55}usd and usd\underline{\rm 56}),usd are studied in relation to their methyl analogues.
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