title: Chiral Self-Recognition between Stereogenic Tetrapalladium Units Affording Pd8Chains Supported by Homochiral Tetraphosphines.
abstract: By using a chiral tetraphosphine, rac-bis[(diphenylphosphinomethyl)phenylphosphino]methane (rac-dpmppm), linear octapalladium chains were synthesized as discrete molecules of [Pd8(μ-rac-dpmppm)4L2](BF4)4(L=CH3CN, dmf, XylNC), [Pd8(μ-rac-dpmppm)4](BF4)4, and [Pd8(μ-rac-dpmppm)4(Cl)2](BF4)2, which are stable in the solution states and characterized by spectroscopic and crystallographic methods to reveal the octapalladium chains supported by homochiral four tetraphosphines. Variable-temperature NMR studies for a 1:1 mixture of [Pd8(μ-rac-dpmppm)4(dmf)2](BF4)4and [Pd8(μ-meso-dpmppm)4(dmf)2]-(BF4)4in [D7]DMF revealed that the Pd8chains were dissociated at higher temperature (T≈140 °C) into the Pd4units of {Pd4(μ-rac-dpmppm)2}2+and {Pd4(μ-meso-dpmppm)2}2+, and they were thermodynamically self-aligned to restore the Pd8chains at lower temperature (T<60 °C), through perfect chiral self-recognition between the stereogenic tetrapalladium units.
authors.affiliation: Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-nishi-machi, Nara, 630-8506, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Tanase
authors.affiliation: Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-nishi-machi, Nara, 630-8506, Japan.
authors.forename: Konomi
authors.initials: K
authors.lastname: Morita
authors.affiliation: Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-nishi-machi, Nara, 630-8506, Japan.
authors.forename: Risa
authors.initials: R
authors.lastname: Otaki
authors.affiliation: Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-nishi-machi, Nara, 630-8506, Japan.
authors.forename: Kana
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-nishi-machi, Nara, 630-8506, Japan.
authors.forename: Yukino
authors.initials: Y
authors.lastname: Kaneko
authors.affiliation: Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-nishi-machi, Nara, 630-8506, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Nakamae
authors.affiliation: Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-nishi-machi, Nara, 630-8506, Japan.
authors.forename: Bunsho
authors.initials: B
authors.lastname: Kure
authors.affiliation: Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-nishi-machi, Nara, 630-8506, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nakajima
keywords: chiral self-recognition; metal atom chains; octanuclear complexes; palladium; tetraphosphines