Nobuko Komatsuzaki

Synthesis and structure of planar-chiral (1,2,4-trisubstituted cyclopentadienyl) cobalt(tetraarylcyclobutadiene) complexes containing three different chiralities in one molecule☆

Abstract The first diastereomerically pure planar-chiral cyclopentadienyl-cobalt complexes ( 4 and 5 ) have been synthesised by the reaction of CoCl(PPh 3 ) 3 with a trisubstituted cyclopentadienyl anion having a (−)-menthyl group in the presence of diarylacetylenes. Removal of the menthyl group from 4a and 5a afforded the first optically pure enantiomers of planar-chiral cyclopentadienylcobalt complexes, (+)- and (−)- 6 , and (+)- and (−)- 7 . The molecular structure including absolute configuration of 4a has been established by a single-crystal X-ray structure analysis. Crystallographic data for 4a : orthorhombic, space group P 2 1 2 1 2 1 ; a = 18.602(10), b = 15.629(3), c = 13.893(3) A; Z = 4; R = 0.051, R w = 0.057. The structure of 4a indicates that there exist three different chiralities [planar (Cp′-Co moiety), central ((−)-menthyl group), and helical (C 4 Ar 4 -moiety) chiralityl in one molecule. These complexes provide not only the first optically pure planar-chiral Cp′-Co complexes but also the first examples containing three different chiralities in one molecule.

Synthesis of planar-chiral cobalticinium complexes and their properties as chiral anion receptors

Abstract The first enantiomerically pure planar-chiral cobalticinium complexes have been synthesized and shown to behave as anion receptors which can recognize the chirality of camphor-10-sulfonate.

Structure and photochemical properties of ruthenium complexes having dimethyl-substituted DPPZ or TPPHZ as a ligand

Novel ruthenium complexes having 4,7-dimethyl-substituted DPPZ or TPPHZ as a ligand have been synthesized: the methyl groups on the ligands exert a shielding effect on the phenazine nitrogens which prevents solvent-quenching.

Synthesis and structure of planar-chiral cyclopentadienyl–cobalt(I) complexes: three different chiralities in one molecule

Diastereoisomerically pure planar-chiral cyclopentadienyl–cobalt complexes, 4 and 5, were prepared by the reaction of a trisubstituted cyclopentadiene bearing a (–)-menthyl group with [CoCl(PPh3)3] and acetylenes, and removal of the menthyl group from 4a and 5a afforded the optically pure enantiomers, (+)- and (–)-6, respectively; an X-ray structural analysis of 4a has revealed that there exist three different chiralities (planar, carbon-centred and helical) in one molecule.

Synthesis of planar-chiral cobalticinium complexes

Abstract Planar-chiral cobalticinium complexes having a carboxylic function were synthesized in an enantiomerically pure form and transformed into several derivatives such as amide, ester and alcohol. The molecular structure including absolute configuration of 8b was established by a single-crystal X-ray structure analysis. Based on the configuration of the (−)-menthyl group, the absolute configuration of 8b around the CpM moiety was determined to be R .

A metal-organic molecular box obtained from self-assembling around uranyl ions

We used the peculiar coordination geometry of uranyl ions to build a three-dimensional superstructure of inprecedented architecture. The complexation of uranyl ions by a monoester derivative of the cis,trans regioisomer of Kemp’s triacid and µ-peroxo bridges leads a cagelike molecule with a roughly parallelepipedic inner cavity of ca. 700 A3 able to host four medium-sized organic molecules.

A new route to planar-chiral cyclopentadienyl-iron(II) and -rhodium(I) complexes

Diastereoisomerically pure planar-chiral cyclopentadienyl-metal complexes, 3 and 4, are prepared by the reaction of the cyclopentadiene 2 having a (–)-menthyl group with FeCl2 or [Rh(cod)Cl]2(cod = cylcloocta-1,5-diene); removal of the (–)-menthyl group from 4 affords the first optically pure enantiomers, (+)-5 and (–)-5.