Alkyl(amino)- and Alkyl(chloro)phosphanyl-Substituted Cyclopentadienyl Complexes of Titanium and Zirconium

Abstract

Keywords: Titanium / Zirconium / Cyclopentadienyl ligands / P ligands / PolymerisationPhosphanyl-substituted cyclopentadienes of the type [R n Cp−PR(NR 1 R 2 /Cl)] (1−22) (R = Alk, Ar; R 1 , R 2 = H, Alk, Ar, SiR 3 ; R n Cp = tBuCp, Me 4 Cp, Ind, Me 6 Ind, Flu) can be synthesised by reaction of alkyldichlorophosphanes and alkyl(amino)chlorophosphanes with alkali metal cyclopentadienides. The method used is a general one and provides high isolated yields of the target compounds. The phosphanylcyclopentadienes can easily be deprotonated by strong bases (e.g. nBuLi, PhCH 2 K, Ph 2 CHK) and the potassium salts [R n Cp−PR(NR 1 R 2 )]K (25−28) are efficiently transmetallated by Me 3 SnCl. A subsequent reaction with TiCl 4 (L) 2 and ZrCl 4 (L) 2 (L = THF, tetrahydrothiophene, Me 3 P) affords new half-sandwich complexes [{Me 4 Cp−PtBu(NEt 2 )}TiCl 3 ] (36), [{Me 4 Cp−PtBu(NEt 2 )}TiCl 3 ] (37) and [{tBuCp−PtBu-(NEt 2 )}TiCl 3 ] (38) in moderate yields. The reaction of [tBuCp−PtBu(Cl)] (6) with TiCl 4 in the presence of Et 3 N at low temperature yields the half-sandwich complex

Synthesis and reactivity of a tethered diene cyclopentadiene, (C5Me4H)SiMe2(CH2CHCHCHCH2), and its alkali metal salts

“…(4)). [C 5 Me 4 P( t Bu)(NEt 2 )]TiCl 3 was previously made in a similar way from Me 3 SnC 5 Me 4 P( t Bu)(NEt 2 ) and TiCl 4 [30]. Complex 4 crystallizes with the extended structure shown in Fig.…”

“…2), e.g. (C 5 H 5 )TiCl 3 [34], [C 5 Me 4 P( t Bu)(NEt 2 )]TiCl 3 [30], and (C 5 Me 4 -CH 2 CH 2 Ph)TiCl 3 [35] ( Table 4). The three independent Ti Ã/C bond lengths are 2.306 (2) …”

Titanium: Organometallic Chemistry

“…99 In an analogous manner, treatment of (Cp-P-t-BuCl) 2 CMe 2 with one equivalent of TiCl 4 in the presence of Et 3 N gives complex [(Cp-P-t-BuCl) 2 CMe 2 ]TiCl 2 . 101 Cationic ansa-(η 5 -cyclopentadienyl)(η 6 -arene) titanium derivatives have been prepared with both Cp and Cp * derivatives. Treatment of TiCl 4 with C 5 H 4 (R)SiMe 3 (R = CMe 2 Ph, CMe 2 CH 2 Ph, CHPh 2 ) gives the corresponding half-sandwich complexes (η 5 -C 5 H 4 R)TiCl 3 Alkylation of (η 5 -C 5 H 4 R)TiCl 3 gives (η 5 and two-carbon bridges.…”

“…209 Treatment of (t-BuCpP(-t-Bu)Cl)TiCl 3 with LiN(H)-t-Bu in the presence of Et 3 N leads to the formation of the constrained geometry complex (η 5 :η 1 -tBuCpP(-t-Bu)N-t-Bu)TiCl 2 in high yield. 101 Constrained geometry complexes with other π ligands have also been prepared. Treatment of (4-Dimethylsilyl-tertbutylamido)-N ,N -diisopropyl-1-aminoboratabenzene with two equivalents of t-BuLi followed by treatment with TiCl 4 gives (4-Dimethylsilyl-tert-butylamido)-N ,N -diisopropyl-1-aminoboratabenzene titanium dichloride complexes (46).…”

Synthesis, structure and ethylene polymerization behavior of titanium phosphinoamide complexes

“…About the ligand of phosphinoamide, Roesky et al [18] reported homoleptic phosphinoamide complexes of lanthanide. Recently, Kotov et al [19] reported the phosphorusbridged Cp-amide Ti complex, which produced linear, high-molecular-weight PE with an activity of 10 5 g/ (mol Ti h bar). We have also prepared a series of nonbridged phosphinoamide cyclopentadienyl complexes of titanium.…”