Resolution of seven-coordinate complexes.

The crystal structures of [Pr(dbm)3H2O] (1), [Sm(dbm)3H2O] (2), and [Er(dbm)3H2O] (3) have been determined (dbm=dibenzoylmethane). They display seven-coordinate propeller-shaped molecules, which are chiral and crystallize as conglomerates in space group R3. Analysis of the crystal structures reveals supramolecular interactions, including formation of a quadruple helix, which explain how stereochemical information can be transferred between stacks of molecules. A method to quantify the ee in bulk samples of stereochemically labile compounds by using solid-state CD spectroscopy is described. Using this method, it has been shown that compounds 1-3 undergo total spontaneous resolution directly after synthesis, forming a microcrystalline reaction product that is essentially enantiopure. The resolution of bulk quantities of seven-coordinate complexes (without chiral or polydentate ligands) is thus reported for the first time. Because the crystallization starts without seeding, the overall preparation may be regarded as absolute asymmetric synthesis.

[1]  M. Nishio.  CH/π hydrogen bonds in crystals , 2004 .

[2]  D. Singleton,et al.  A few molecules can control the enantiomeric outcome. Evidence supporting absolute asymmetric synthesis using the Soai asymmetric autocatalysis. , 2003, Organic letters.

[3]  M. Håkansson,et al.  Absolute asymmetric synthesis of "chiral-at-metal" Grignard reagents and transfer of the chirality to carbon. , 2003, Chemistry.

[4]  J. Siegel.  Chemistry: Shattered mirrors , 2002, Nature.

[5]  L. Vo,et al.  Enantioselective synthesis without discrete optically active additives. , 2002, Journal of the American Chemical Society.

[6]  Alan Saghatelian,et al.  A chiroselective peptide replicator , 2001, Nature.

[7]  Davidsson,et al.  Octahedral Grignard Reagents Can Be Chiral at Magnesium This work was supported by the Swedish Natural Science Research Council (NFR). We thank Karin Bengtsson, Fredrik Blomgren, Henrik Glänneskog, and Dan Lundberg for preparative assistance. , 2000, Angewandte Chemie.

[8]  P. Cintas,et al.  Chiral autocatalysis: where stereochemistry meets the origin of life , 2000 .

[9]  Gérald Bernardinelli,et al.  Reporting and evaluating absolute-structure and absolute-configuration determinations , 2000 .

[10]  G. Rikken,et al.  Enantioselective magnetochiral photochemistry , 2000, Nature.

[11]  Kuroda,et al.  CD spectra of solid-state samples , 2000, Chirality.

[12]  MacDermott.  The ascent of parity-violation: exochirality in the solar system and beyond , 2000, Enantiomer.

[13]  W. Bonner,et al.  Parity violation and the evolution of biomolecular homochirality. , 2000, Chirality.

[14]  Ben L. Feringa,et al.  Absolute asymmetrische Synthese: Ursprung, Beeinflussung und Verstärkung von Chiralität , 1999 .

[15]  R. Delden,et al.  Absolute Asymmetric Synthesis: The Origin, Control, and Amplification of Chirality. , 1999, Angewandte Chemie.

[16]  G. Bernardinelli,et al.  Absolute structure and absolute configuration. , 1999, Acta crystallographica. Section A, Foundations of crystallography.

[17]  Mikael Håkansson,et al.  ISOLIERUNG UND SPONTANE ENANTIOMERENTRENNUNG VON ACHTFACH KOORDINIERTEN SAMARIUMKOMPLEXEN , 1999 .

[18]  Vestergren,et al.  Isolation and Spontaneous Resolution of Eight-Coordinate Stereoisomers. , 1999, Angewandte Chemie.

[19]  Louis J. Farrugia,et al.  WinGX suite for small-molecule single-crystal crystallography , 1999 .

[20]  Pedro Cintas,et al.  Absolute Asymmetric Synthesis under Physical Fields: Facts and Fictions. , 1998, Chemical reviews.

[21]  J. Siegel.  Homochiral imperative of molecular evolution , 1998 .

[22]  Louis J. Farrugia,et al.  ORTEP-3 for Windows - a version of ORTEP-III with a Graphical User Interface (GUI) , 1997 .

[23]  J. Bada.  Origins of homochirality , 1995, Nature.

[24]  L. Addadi,et al.  Resolution of conglomerates with the assistance of tailor-made impurities. Generality and mechanistic aspects of the "rule of reversal". A new method for assignment of absolute configuration , 1982 .

[25]  L. Addadi,et al.  Resolution of conglomerates by stereoselective habit modifications , 1982, Nature.

[26]  R. Palmer,et al.  Single-crystal electronic absorption of tris(1,3-diphenyl-1,3-propanedionato)aquoneodymium(III): oscillator strength of the 4I9/2 .fwdarw. 4G5/2 hypersensitive transition , 1981 .

[27]  D. Karraker,et al.  Crystal and molecular structure of the heptacoordinate complex tris(diphenylpropanedionato)aquoholmium, Ho(PhCOCHCOPh)3.H2o , 1969 .

[28]  R. Charles,et al.  Rare earth dibenzoylmethides preparation, dehydration and thermal stability , 1964 .