12116-66-4

Usage

Uses

Used in Chemical Research:
BIS(CYCLOPENTADIENYL)HAFNIUM DICHLORIDE is used as a starting material for the preparation of many kinds of hafnocene(II or IV) derivatives, which are essential in various chemical reactions and processes.
Used in Pharmaceutical Industry:
BIS(CYCLOPENTADIENYL)HAFNIUM DICHLORIDE is used as a pharmaceutical intermediate, playing a crucial role in the synthesis of various pharmaceutical compounds.
Used in Glycosyl Fluoride Activation:
In combination with AgI salt, BIS(CYCLOPENTADIENYL)HAFNIUM DICHLORIDE is used as an effective activator for glycosyl fluoride, which is an important reagent in carbohydrate chemistry and the synthesis of various biologically active compounds.
Overall, BIS(CYCLOPENTADIENYL)HAFNIUM DICHLORIDE is a valuable compound with diverse applications in chemical research, pharmaceutical industry, and glycosyl fluoride activation, making it an essential component in the development of new materials and drugs.

Upstream product

• 56-23-5 tetrachloromethane 
• 13499-05-3 hafnium tetrachloride 
• 1079-66-9 chloro-diphenylphosphine 
• 96454-42-1 {(cyclopentadienyl)2(o-diphenylphosphinobenzyl)HfCl} 
• 96454-40-9 {(cyclopentadienyl)2(o-dimethylaminobenzyl)HfCl} 
• 69249-21-4 tris-tert-butylphosphinimide, lithium salt 
• 1192053-68-1 chloro(η5-cyclopentadienyl)bis(tris(tert-butyl)phosphinimide)hafnium(IV) 
• 77-73-6 bi(cyclopentadiene) 
• 542-92-7 cyclopenta-1,3-diene 
• 1309569-80-9 3-cyclopentadienyl-3-methylbutanenitrile lithium salt 
• 3559-74-8 trimethylsilylcyclopentadiene 

Downstream Products

• 110682-58-1 1,1-bis(cyclopentadienyl)-2,3-diphenyl-1-hafnacyclopent-2-ene 
• 86013-27-6 hafnocene di((Cy₂)phosphide) 
• 86013-28-7 hafnocene di((Ph₂)phosphide) 
• 84879-48-1 bis(phenylethynyl)hafnocene 
• 85289-44-7 (η5-cyclopentadienyl)(S2CN(C2H5)(C6H4CH3))3hafnium(IV) 

Relevant academic research and scientific papers

PREPARATION AND CHEMICAL BEHAVIOUR OF HALOCYCLOPENTADIENYL-ZIRCONIUM(III) AND -HAFNIUM(III)

Reduction of (η5-C5H5)2MCl2 (M=Zr, Hf) with one equivalent of Na/Hg gives 5-C5H5)2M(μ-Cl)>2.The zirconium(III) complex is also obtained from reactions between LiCp and 2>2 (L2=2P-n-Bu3, dppe) or solutions of ZrCl4 previously reduced with Na/Hg.These zirconium(III) and hafnium(III) complexes are oxidized by AgBF4 or TlBF4 to the cationic 5-C5H5)2M(μ-Cl)>22+ complexes, which react with monodentate ligands to give 5-C5H5)MClL>+ (L=OPPh3, NHPh2) and with bidentate ligands to give dinuclear cationic derivatives5-C5H5)2MCl>2(μ-L-L)>2+ (L-L-dppe, 2,2'-bipyridine).Similar complexes can also be obtained from (η5-C5H5)2MCl2 by halide abstraction with a silver salt.Oxidation of zirconium(III) and hafnium(III) derivatives with halogens gives (η5-C5H5)MClX (X=Cl, Br) and 5-C5H5)2ZrCl(OPPh3)>I3.Conductivity, magnetic susceptibility and IR and NMR data are discussed.

Structural diversity in tris(cyclopentadienyl) complexes of the Group 4 metals: Synthesis of Cp and MeCp complexes of Zr and Hf, and crystallographic characterization of (MeCp)3HfCl and (MeCp)4Zr (MeCp = C5H4CH3)

Previous theoretical studies have predicted structural differences between the tris(cyclopentadienyl) zirconium and hafnium complexes Cp3MX (Cp = C5H5;M = Zr, Hf). Cp3ZrCl can be isolated via the stoichiometric reaction of Cp2ZrCl2 and NaCp, but forming the analogous Hf complex is complicated by ligand redistribution. Partial crystallographic analysis of these two complexes indicates likely structural differences wherein the Zr complex has three η5 Cp ligands ("3-5" structure) while the Hf complex has two η5 Cp ligands and one η1 Cp ligand ("2-5,1-1" structure). The use of C5H4CH 3 (MeCp) simplifies both the syntheses and the procurement of suitable crystals. The preparation of a number of MeCp complexes of Zr and Hf is reported along with crystallographic characterization of (MeCp) 3HfCl, which has a 2-5,1-1 structure and (MeCp)4Zr, which has a 3-5,1-1 structure.

THERMAL DECOMPOSITION OF BIS(CYCLOPENTADIENYL)HAFNIUM COMPOUNDS AND THEIR DEUTERATED ANALOGUES

Thermal decomposition ranges of Cp2HfR2 (R=Me, Ph) have been found by the DTA method.The thermal stability of hafnium derivatives greatly exceeds the stability of analogous titanium and zirconium compounds.Decomposition of Cp2HfR2 occurs by abstraction of ?-bonded groups which convert into RH.Hydrogen donors for the RH formation are both ?-cyclopentadienyl and ?-bonded groups.The initial ?-Cp2Hf structure rearranges to form the (η5-Cp)-(η5,η1-C5H4)Hf fragment.These react with HCl to produce Cp2HfCl2.It has been established that hydrogen exchange between cyclopentadienyl rings and methyl groups occurs during the thermal decomposition of Cp2HfMe2.As a result of the exchange process on thermal decomposition of Cp2HfMe2-d6, deuterium insertion into the cyclopentadienyl ring has been shown.The participation of solvent during the decomposition process of the hafnium derivatives has been studied.

Photoresist based on metallocene compound and preparation method and application thereof

The invention belongs to the technical field of photoresist, and particularly relates to a photoresist based on a metallocene compound as well as a preparation method and application of the photoresist. The metallocene compound disclosed by the invention adopts metal as a central core structure, so that the metallocene compound has a relatively high melting point and glass-transition temperature, can meet the requirements of a photoetching technology, and is stable in structure, and a film structure is not changed during high-temperature baking. In addition, the photoresist composition provided by the invention can be used in modern photoetching processes such as 248nm photoetching, 193nm photoetching, extreme ultraviolet (EUV) photoetching, nanoimprint lithography (NIL), electron beam lithography (EBL) and the like, and is particularly suitable for being used in an extreme ultraviolet (EUV) photoetching process.

Palladium-Catalyzed Reductive Coupling Reaction of Terminal Alkynes with Aryl Iodides Utilizing Hafnocene Difluoride as a Hafnium Hydride Precursor Leading to trans-Alkenes

Herein, we describe a reductive cross-coupling of alkynes and aryl iodides by using a novel catalytic system composed of a catalytic amount of palladium dichloride and a promoter precursor, hafnocene difluoride (Cp2HfF2, Cp=cyclopentadienyl anion), in the presence of a mild reducing reagent, a hydrosilane, leading to a one-pot preparation of trans-alkenes. In this process, a series of coupling reactions efficiently proceeds through the following three steps: (i) an initial formation of hafnocene hydride from hafnocene difluoride and the hydrosilane, (ii) a subsequent hydrohafnation toward alkynes, and (iii) a final transmetalation of the alkenyl hafnium species to a palladium complex. This reductive coupling could be chemoselectively applied to the preparation of trans-alkenes with various functional groups, such as an alkyl group, a halogen, an ester, a nitro group, a heterocycle, a boronic ester, and an internal alkyne.

Group 4 metallocene complexes with pendant nitrile groups

The preparation of a new functionalized cyclopentadienyl ligand bearing a nitrile pendant substituent, (C5H4CMe2CH 2CN)- is reported. The corresponding lithium salt of this ligand (1) was prepared by the reaction of in situ lithiated acetonitrile with 6,6-dimethylfulvene. The ligand was subsequently utilized for the synthesis of group 4 metal complexes [(η5-C5H4CMe 2CH2CN)2MCl2] (M = Ti, 2; M = Zr, 3; M = Hf, 4), [(η5-C5H5) (η5-C5H4CMe2CH 2CN)MCl2] (M = Ti, 7; M = Zr, 8), and [(η5- C5Me5) (η5 C5H 4CMe2CH2CN)2ZrCl2] (9). Alternative route to 2 comprised the preparation of half-sandwich complex [(η5-C5H4CMe2CH 2CN)TiCl3] (6). The prepared compounds were characterized by common spectroscopic methods and the solid state structures of complexes 2, 3, 4, 7, and 9 were determined by the single-crystal X-ray diffraction analysis. In addition, compound 7 was converted to the corresponding dimethyl derivative [(η5-C5H5) (η5-C 5H4CMe2CH2CN)TiMe2] (10) and also treated with the chloride anion abstractor Li[B(C6F 5)4] to generate the cationic complex with the coordinated nitrile group, as suggested by the NMR spectroscopy. A formation of yet another cationic complex was observed upon treating compound 10 with (Ph 3C)[B(C6F5)4].

Hafnium-phosphinimide complexes

A series of phosphinimide complexes of Hf are prepared and characterized. Reaction of the phosphinimine t-Bu3PNH with Hf(NEt2) 4 gave (t-Bu3PN)Hf(NEt2)3 (1) but this species was not readily

Cyclopentadienylmetal trichloride formation versus metallocene dichloride formation in the reactions of silylated cyclopentadienes with zirconium and hafnium chlorides. Crystal structure of (1,3-bis- (trimethylsilyl)cyclopentadienyl)titanium trichloride

The reaction of zirconium and hafnium tetrachlorides with tris(trimethylsilyl)cyclopentadiene affords the monocyclopentadienyl complexes (1,3-bis(trimethylsily)cyclopentadienyl)zirconium trichloride (1, 73%) and (1,3-bis(trimethylsilyl)cyclopentadienyl)hafnium trichloride (2, 76%) in good isolated yields. The reaction of 1 with (1,3-bis(trimethylsilyl)cyclopentadienyl)lithium affords 1,1′,3,3′-tetrakis(trimethylsilyl)zirconocene dichloride (74%). In contrast to the preparations of 1 and 2, reaction of bis(trimethylsilyl)cyclopentadiene with zirconium and hafnium tetrachlorides affords 1,1′-bis- (trimethylsilyl)zirconocene dichloride (5, 73%) and 1,1′-bis(trimethylsilyl)hafnocene dichloride (6, 76%). The reaction of (trimethylsilyl)cyclopentadiene with zirconium and hafnium tetrachlorides affords zirconocene dichloride (7, 91%) and hafnocene dichloride (8, 90%). The intermediacy of monocyclopentadienyl species in the preparation of the metallocene dichlorides is supported by the reaction of cyclopentadienylzirconium trichloride with (trimethylsilyl)cyclopentadiene to afford 7 (85%). Reaction of zirconium tetrachloride with 1 equiv of (trimethylsilyl)cyclopentadiene at 0 °C for 0.5 h affords 7 and cyclopentadienylzirconium trichloride in a (69 ± 2):(31 ± 2) ratio. The silyl group regiochemistry in 1 and 2 was established through an X-ray crystal structure determination of the titanium analogue (1,3-bis(trimethylsilyl)cyclopentadienyl)titanium trichloride (3). Complex 3 crystallizes in the orthorhombic space group Pbnm with a = 7.459 (3) angstrom, b = 11.799 (3) angstrom, c = 20.535 (3) angstrom, V = 1807.1 (9) angstrom3, and Z = 4.

Some metallabicyclo-octadienes and -nonadienes of dicyclopentadienyltitanium, -zirconium and -hafnium

Titanocene, zirconocene, and hafnocene dichlorides were reduced in the presence of terminally disubstituted 1,6-heptadiyne or 1,7-octadiyne to produce dicyclopentadienylmetallabicyclooctadienes and -nonadienes.The compounds were characterized by elemental

Transition Metal-Phosphide Chemistry: Synthesis of (M(η-C5H5)2(PR2)2) (M=Zr, R=Ph; M=Hf, R=Ph or cyclo-C6H11) and ((M(η-C5H5)2(PR2))2) (M=Ti, R=Ph or Me; M=Zr or Hf, R=Me), and their Reactions with Protic and Halogen-containing Species

Reactions of the metallocene dichlorides (M(cp)2Cl2) (M=Ti, Zr, or Hf; cp=η-C5H5) with stoicheiometric amounts of LiPR2 (R= Me, Ph, or cyclo-C6H11) yield either the direct exchange products (M(IV)(cp)2(PR2)2) (M=Zr, R=Ph; M=Hf, R=Ph or C6H11) or the reduced species ((M(III)(cp)2 (PR2))2) M=Ti, R=Me or Ph; M=Zr or Hf, R=Me).Spectral (i.r. and (1)H n.m.r.) characterisation of these compounds is presented and discussed with suggestions of possible structures.Treatment of (Zr(cp)2(PPh2)2) with PPh3Cl affords the 'mixed' chloro-phosphido-compound (Zr(cp)2Cl(PPh2)).Reactions of both the M(IV) and M(III) species with halogen-containing and protic reagents have been investigated.Each series reacts with smooth cleavage of the M-P bond(s), but whereas the compounds (M(cp)2(PR2)2) (M=Ti, Zr, or Hf) show simple metathetical exchange, ((M(cp)2(PR))2)usually (and in the case of M=Zr or Hf exclusively) also incorporate metal oxidation M(III) M(IV) into their reactions.