TY - JOUR

T1 - The first late-transition-metal cyclopentadienyl chelate complexes with silylphosphane or secondary phosphane tethers

AU - Werner, Irina

AU - Butenschön, Holger

PY - 2014/11/6

Y1 - 2014/11/6

N2 - While phosphane-tethered cyclopentadienyl complexes with tertiary phosphane moieties have extensively been investigated for many metals, this is not the case for such complexes with a secondary phosphane tether. Only a few representatives of such complexes with early-transition-metals are known. Here, we report the first late-transition-metal cyclopentadienyl chelate complexes with silylphosphane or secondary phosphane tethers. The respective ligand system is generated by nucleophilic opening of spiro[2.4]hepta-4,6-diene with lithium tert-butylphosphide. The anionic ligand is trapped with iron(II) chloride with formation of the respective ferrocene derivative. Treatment of lithium tert-butylphosphide with tert-butylchlorodimethylsilane or with chlorotriisopropylsilane affords the respective secondary silylphosphanes. Deprotonation, reaction with spiro[2.4]hepta-4,6-diene, followed by treatment with nickel dihalide complexes affords the respective nickel cyclopentadienylalkylsilylphosphane chelates as the first representatives of their kind. Their halide ligands can easily be exchanged by methylation with methyllithium or by reaction with trimethylsilyl cyanide to give the respective cyano chelate. Under the chromatographic conditions applied, this complex undergoes a protiodesilylation to give the first secondary cyclopentadienylalkylphosphane chelate of a late-transition-metal, which has been characterized by X-ray crystallographic analysis. Alternatively, deprotonation of the extremely sterically crowded primary (2,4,6-tri-tert-butylphenyl)phosphane followed by nucleophilic ring opening of spiro[2.4]hepta-4,6-diene and reaction of the anionic ligand system with NiBr2(thf)2 directly affords the respective cyclopentadienylalkylphosphane nickel chelate with a secondary phosphane ligand.

AB - While phosphane-tethered cyclopentadienyl complexes with tertiary phosphane moieties have extensively been investigated for many metals, this is not the case for such complexes with a secondary phosphane tether. Only a few representatives of such complexes with early-transition-metals are known. Here, we report the first late-transition-metal cyclopentadienyl chelate complexes with silylphosphane or secondary phosphane tethers. The respective ligand system is generated by nucleophilic opening of spiro[2.4]hepta-4,6-diene with lithium tert-butylphosphide. The anionic ligand is trapped with iron(II) chloride with formation of the respective ferrocene derivative. Treatment of lithium tert-butylphosphide with tert-butylchlorodimethylsilane or with chlorotriisopropylsilane affords the respective secondary silylphosphanes. Deprotonation, reaction with spiro[2.4]hepta-4,6-diene, followed by treatment with nickel dihalide complexes affords the respective nickel cyclopentadienylalkylsilylphosphane chelates as the first representatives of their kind. Their halide ligands can easily be exchanged by methylation with methyllithium or by reaction with trimethylsilyl cyanide to give the respective cyano chelate. Under the chromatographic conditions applied, this complex undergoes a protiodesilylation to give the first secondary cyclopentadienylalkylphosphane chelate of a late-transition-metal, which has been characterized by X-ray crystallographic analysis. Alternatively, deprotonation of the extremely sterically crowded primary (2,4,6-tri-tert-butylphenyl)phosphane followed by nucleophilic ring opening of spiro[2.4]hepta-4,6-diene and reaction of the anionic ligand system with NiBr2(thf)2 directly affords the respective cyclopentadienylalkylphosphane nickel chelate with a secondary phosphane ligand.

KW - Arene ligands

KW - Chelates

KW - Nickel

KW - Phosphane ligands

KW - Transition metals

UR - http://www.scopus.com/inward/record.url?scp=84916203069&partnerID=8YFLogxK

U2 - 10.1002/ejic.201402886

DO - 10.1002/ejic.201402886

M3 - Article

AN - SCOPUS:84916203069

VL - 2014

SP - 6051

EP - 6060

JO - European Journal of Inorganic Chemistry

JF - European Journal of Inorganic Chemistry

SN - 1434-1948

IS - 35

ER -