Abstract: In an embodiment, a method for producing a polyolefin is provided. The method includes: contacting a first composition and a second composition in a line to form a third composition, wherein: the first composition comprises a contact product of a first catalyst, a second catalyst, a support, and a diluent, wherein the mol ratio of second catalyst to first catalyst is from 60:40 to 40:60, the second composition comprises a contact product of the second catalyst and a second diluent; introducing the third composition from the line into a gas-phase fluidized bed reactor; exposing the third composition to polymerization conditions; and obtaining a polyolefin.

Abstract: Methods for preparing a metallocene-based catalyst composition that can impact the long chain branching of ethylene homopolymers and copolymers produced using the catalyst composition are described. The catalyst composition can be prepared by contacting a metallocene compound, a hydrocarbon solvent, and a first organoaluminum compound for a first period of time to form a metallocene solution, and then contacting the metallocene solution with an activator-support and a second organoaluminum compound for a second period of time to form the catalyst composition.

Abstract: A complex of formula (I): (I?) M is Hf; each X is a sigma ligand; L is a bridge of formula -(ER82)y—; y is 1 or 2; E is C or Si; each R8 is independently a C1-C20-hydrocarbyl, tri(C1-C20-alkyl)silyl, C6-C20-aryl, C7-C20-arylalkyl or C7-C20-alkylaryl or L is an alkylene group such as methylene or ethylene; Ar and Ar? are each independently an aryl or heteroaryl group optionally substituted by 1 to 3 groups R1 or R1? respectively; R1 and R1? are each independently the same or can be different and are a linear or branched C1-C6-alkyl group, C7-20 arylalkyl, C7-20 alkylaryl group or C6-20 aryl group with the proviso that if there are four or more R1 and R1? groups present in total, one or more of R1 and R1? is other than tert butyl; R2 and R2? are the same or are different and are a CH2—R9 group, with R9 being H or linear or branched C1-C6-alkyl group, C3-8 cycloalkyl group, C6-10 aryl group; each R is a —CH2—, —CHRx- or C(Rx)2- group wherein Rx is C1-4 alkyl and where m is 2-6; R5 is a linear or branched C1-C6-a

Abstract: The present disclosure provides bridged metallocene catalyst compounds comprising —Si—Si— bridges, catalyst systems comprising such compounds, and uses thereof. Catalyst compounds of the present disclosure can be hafnium-containing compounds having one or more cyclopentadiene ligand(s) substituted with one or more silyl neopentyl groups and linked with an Si—Si-containing bridge. In another class of embodiments, the present disclosure is directed to polymerization processes to produce polyolefin polymers from catalyst systems comprising one or more olefin polymerization catalysts, at least one activator, and an optional support.

Abstract: Catalyst system for producing ethylene copolymers in a high temperature solution process, the catalyst system comprising: (i) a metallocene complex of formula (I) wherein M is Hf or a mixture with Zr, provided that more than 50% by moles of the complex of Formula I has M=Hf; X is a sigma ligand; R are the same or different from each other and can be saturated linear or branched C1-C10 alkyl, C6-C10 aryl, C4-C10 heteroaryl, C6-C20 alkylaryl or C6-C20 arylalkyl groups, which can optionally contain up to 2 heteroatoms or silicon atoms; R1 is a C6-C10 aryl or C6-C20 alkylaryl group optionally containing up to 2 heteroatoms or silicon atoms or a C4-C10 heteroaryl group; R2 is a C4-C20 cycloalkyl group, optionally carrying alkyl substituents in beta-positions, of formula (II) in which R? can be the same or can be different from each other and can be hydrogen or is defined as R and n is 1 to 17; and (ii) a boron containing cocatalyst.

Abstract: Disclosed are Silicon- and Zirconium-containing precursors having one of the following formulae: wherein each R1, R2, R3, R4, R5, R6, R7, R8, R9 and R10 is independently selected from H; a C1-C5 linear, branched, or cyclic alkyl group; or a C1-C5 linear, branched, or cyclic fluoroalkyl group. Also disclosed are methods of synthesizing the disclosed precursors and using the same to deposit Zirconium-containing thin films on substrates via vapor deposition processes.

Abstract: A racemic complex of formula (I), wherein M is zirconium or hafnium; each X is a sigma ligand; L is a divalent bridge selected from —R?2C—, —R?2C—CR?2, —R?2Si—, —R?2Si—SiR?2—, —R?2Ge—, wherein each R? is independently a hydrogen atom, C1-20-hydrocarbyl, tri(C1-20-alkyl)silyl, C6-20-aryl, C7-20-arylalkyl or C7-20-alkylaryl; R2 and R2? are each independently a C1-20 hydrocarbyl radical optionally containing one or more heteroatoms from groups 14-16; R5? is a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16 and optionally substituted by one or more halo atoms.

Abstract: The invention relates to compounds, in particular phosphinic ligands of metal complexes, as well as to metal complexes including said ligands and to supported catalysts including said metal complexes or said compounds. The invention also relates to methods for synthesizing said compounds, to complexes, and to supported catalysts, as well as to intermediate products used in said synthesis methods. The invention further relates to the uses of said compounds. The compounds of the invention are ferrocene compounds which have been functionalized so as to be capable of being heterogenized. The invention can be used in particular in the field of heterogeneous catalysis.

Abstract: This invention relates to unsymmetrical metallocenes, catalyst systems therefrom and their use to make highly isotactic polypropylene.

Abstract: The present invention provides methods of making stereo-enriched ansa-metallocene compounds using an unchelated amine compound. Generally, these methods result in a rac:meso isomer selectivity of the stereo-enriched ansa-metallocene compound of greater than 4:1.

Abstract: Disclosed is a catalytic component for trimerization containing a transition metal complex with which 1-hexene can be produced efficiently with excellent selectivity, even under high temperature conditions, by means of an ethylene trimerization reaction. Also disclosed is a trimerization catalyst that is obtained by bringing an olefin copolymerization catalyst and an activating co-catalytic component into contact with one another. Said transition metal complex is represented by the following general formula (1), wherein M1 represents a Group 4 transition metal atom, and R1 through R11 and X1 through X3 each independently represent a hydrogen atom, a halogen atom, or a specific organic group.

Abstract: Disclosed is transition metal complex that serves as a catalytic component with which 1-hexene can be produced efficiently with excellent selectivity, even under high temperature conditions, by means of an ethylene trimerization reaction. Said transition metal complex is represented by the following general formula (1), wherein M1 represents a Group 4 transition metal atom, and R1 through R11 and X1 through X3 each independently represent a hydrogen atom, a halogen atom, or a specific organic group.

Abstract: This disclosure relates to an ansa-metallocene compound of a novel structure that can provide various selectivities and activities to polyolefin copolymers, a preparation method thereof, and a method for preparing polyolefins using the ansa-metallocene compound.

Abstract: This invention relates to racemic bridged bis(indenyl)metallocene transition metal compounds, rac-directing metallation reagents and a process to produce the racemic bridged bis(indenyl)metallocene transition metal compounds using the rac-directing metallation regents.

Abstract: This invention relates to a novel group 2, 3 or 4 transition metal metallocene catalyst compound having at least one arenyl ligand substituted with: 1) a cyclopropyl group and, optionally, 2) at least one other group, such as a hydrocarbyl, a heteroatom or a heteroatom containing group.

Abstract: This invention relates to a novel group 2, 3 or 4 transition metal metallocene catalyst compound having two indenyl ligands with identical substitution including, for example, cyclopropyl groups and substituted phenyl groups at the 2 and 4 positions of the catalyst, respectively, where the substituents are at the 3? and 5? positions of the phenyl groups.

Abstract: This invention relates to a novel group 2, 3 or 4 transition metal metallocene catalyst compound that is asymmetric having two non-identical indenyl ligands with substitution at R2 having a branched or unbranched C1-C20 alkyl group substituted with a cyclic group or a cyclic group, R8 is an alkyl group and R4 and R10 are substituted phenyl groups.

Abstract: This invention relates to novel bridged a hafnium transition metal metallocene catalyst compounds having two indenyl ligands substituted at the 4 positions with a C1 to C10 alkyl, where the 3 positions are hydrogen (assuming the bridge position is counted as the one position) and the bridging atom is carbon or silicon which is incorporated into a cyclic group comprising 3, 4, 5, or 6 silicon and/or carbon atoms that make up the cyclic ring.

Abstract: This invention relates to a novel group 4 transition metal metallocene catalyst compound that is asymmetric having two non-identical indenyl ligands with substitution at R2 having a branched C1-C20 alkyl group, R8 having a linear alkyl group and R4 and R10 having substituted phenyl groups, where at least one of R4 and R10 is a phenyl group substituted at the 3 and 5 position.

Abstract: A silicon-bridged Cp-Ar transition metal complex is provided that serves as a catalytic component capable of efficiently and highly selectively producing 1-hexene through the trimerization reaction of ethylene. The transition metal complex is represented by formula (1): wherein M1 represents a transition metal atom of Group 4 of the Periodic Table of the Elements; Ar1 is an aryl group represented by formula (2), Ar2 is an aryl group represented by formula (3) and Ar3 is an aryl group represented by formula (4) (not all of the three aryl groups Ar1, Ar2 and Ar3 are the same at the same time), Wherein each of the X and R groups represents hydrogen or the like.

Abstract: The present invention relates to a ligand compound, a chromium compound, and a catalyst system including the same. The catalyst system including the ligand compound or chromium compound according to the present invention exhibits high catalytic activity in ethylene oligomerization reaction, and therefore, polyethylene can be prepared using a small amount of comonomers or using only ethylene without comonomers.

Abstract: An ethylene copolymer, a Group 4 transition metal catalyst compound, and methods for polymerization using such a compound, said compound represented by the formula: (L)p(R?)zT(Cp)(A)MX2, where M is a Group 4 metal; z is 0 to 8; p is 1 to 3; X is an anionic leaving group; T is a bridging group; R1 to R4 are hydrogen, a hydrocarbyl group, a substituted hydrocarbyl group, aryl group, substituted aryl group, or a heteroatom-containing group (where adjacent R groups can form rings); R? is hydrogen, a C1 to C10 alkyl group, a C6 to C24 aryl group, or a C7 to C40 alkylaryl group; and L is a heteroatom or heteroatom-containing group bound to T, Cp is a cyclopentadienyl ring substituted with 0 to 4 substituent groups (where adjacent groups can form C4 to C20 rings); A is Cp or (JS?z*-1-y), where J is a Group 15 or 16 element; S? is a hydrocarbyl, substituted hydrocarbyl, or heteroatom; z* is 2 or 3, and y is 0 or 1, is provided.

Abstract: Metallocene compounds and pharmaceutical compositions containing these metallocene compounds are disclosed and described. Methods of treating cancer employing such metallocene compounds and pharmaceutical compositions also are provided.

Abstract: A racemic complex of formula (I), wherein M is zirconium or hafnium; each X is a sigma ligand; L is a divalent bridge selected from —R?2C—, —R?2C—CR?2, —R?2Si—, —R?2Si—SiR?2—, —R?2Ge—, wherein each R? is independently a hydrogen atom, C1-20-hydrocarbyl, tri(C1-20-alkyl)silyl, C6-20-aryl, C7-20-arylalkyl or C7-20-alkylaryl; R2 and R2? are each independently a C1-20 hydrocarbyl radical optionally containing one or more heteroatoms from groups 14-16; R5? is a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16 and optionally substituted by one or more halo atoms.

Abstract: An ?-olefin oligomer having the following features (1) to (6), and a method for producing the ?-olefin oligomer using a particular double-crosslinked meso complex provide an ?-olefin oligomer that contains a smaller amount of a dimer component while having a low viscosity, not in accordance with the Schulz-Flory distribution, and a method for producing the same: (1) a trimer component proportion C3 (% by mass) that is larger than a theoretical value obtained from the S—F distribution, (2) a hexamer component proportion C6 (% by mass) that is smaller than a theoretical value obtained from the S—F distribution, (3) a kinematic viscosity at 100° C. of 20 mm2/s or less, (4) a meso triad fraction [mm] measured by 13C-NMR of 40% by mol of less, (5) from 0.2 to 1.

Abstract: This invention relates to bridged metallocene compounds and catalyst systems comprising these bridged metallocene compounds.

Abstract: A method for producing an anionized meso-form double-cross-linked ligand represented by formula (3), including: bringing a compound represented by formula (1) into contact with a compound represented by formula (2) at ?25° C. or less; and introducing an anionizing agent within 5 hours after the contact, wherein R1 to R10 are independently a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or the like; A and A? are independently a cross-linking group containing an atom belonging to the 14th group of the periodic table; M and M? are independently an atom belonging to the 1st or the 2nd group of the periodic table.

Abstract: The present invention provides methods of making stereo-enriched ansa-metallocene compounds using an unchelated amine compound. Generally, these methods result in a rac:meso isomer selectivity of the stereo-enriched ansa-metallocene compound of greater than 4:1.

Abstract: The present invention relates to a novel metallocene compound, a catalyst composition comprising the same, and to olefinic polymers produced using the same. The metallocene compound according to the present invention and the catalyst composition comprising the same can be used when producing olefinic polymers, have outstanding copolymerisation properties, and can produce olefinic polymers of high molecular weight. In particular, when the metallocene compound according to the present invention is employed, highly heat resistant block copolymers can be produced, and olefinic polymers can be produced which have a high melting point (Tm) even if the comonomer content is increased when producing the olefinic polymer.

Abstract: The invention provides for a process for the preparation of a silylferrocene compound, comprising the steps of treating ferrocene with a 4-chloroalkyryl chloride in the presence of an lewis acid catalyst and an organic solvent to obtain the acylated product, reducing the acylated product to obtain the 4-chloralkylferrocene, treating the 4-chloroalkylferroce with a metal under Grignard reaction conditions to form its corresponding Grignard intermediate compound; and reacting with chloroalkylsilane in-situ to give the silylferrocene compound. The silylferrocene compound 4-(dimethylsilyl)butylferrocene can be prepared by the process of the invention.

Abstract: The invention relates to the use of disubstituted alkynes for the functionalisation of the surface of a substrate consisting of a semi-conductor material, with molecules of interest. According to the invention, a compound of formula A-(E1)n1-F1 is used, wherein A is a linear or cyclic disubstituted alkyne, E1 is an alkyl chain and n2 is 0 or 1, and F1 is a reactive group that can react with the reactive group F2 of a compound of formula F2-(E2)n2-X wherein E2 is an alkyl chain and X is a group having properties of interest. The invention is especially applicable to the field of molecular biology or biotechnology.

Abstract: A method for producing an anionized meso-form double-cross-linked ligand represented by formula (3), including: bringing a compound represented by formula (1) into contact with a compound represented by formula (2) at ?25° C. or less; and introducing an anionizing agent within 5 hours after the contact, wherein R1 to R10 are independently a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or the like; A and A? are independently a cross-linking group containing an atom belonging to the 14th group of the periodic table; M and M? are independently an atom belonging to the 1st or the 2nd group of the periodic table.

Abstract: A silicon-bridged Cp-Ar transition metal complex is provided that serves as a catalytic component capable of efficiently and highly selectively producing 1-hexene through the trimerization reaction of ethylene. The transition metal complex is represented by formula (1): wherein M1 represents a transition metal atom of Group 4 of the Periodic Table of the Elements; Ar1 is an aryl group represented by formula (2), Ar2 is an aryl group represented by formula (3) and Ar3 is an aryl group represented by formula (4) (not all of the three aryl groups Ar1, Ar2 and Ar3 are the same at the same time), Wherein each of the X and R groups represents hydrogen or the like.

Abstract: A solid, particulate catalyst comprising: (i) a complex of formula (I) wherein M is zirconium or hafnium; each X is a sigma ligand; L is a divalent bridge selected from —R?2C—, —R?2C—CR?2—, —R?2Si—, —R?2Si—SiR?2—, —R?2Ge—, wherein each R? is independently a hydrogen atom, C1-C20-hydrocarbyl, tri(C1-C20-alkyl)silyl, C6-C20-aryl, C7-C20-arylalkyl or C7-C20-alkylaryl; each R1 is a C4-C20 hydrocarbyl radical branched at the ?-atom to the cyclopentadienyl ring, optionally containing one or more heteroatoms belonging to groups 14-16, or is a C3-C20 hydrocarbyl radical branched at the ?-atom to the cyclopentadienyl ring where the ?-atom is an Si-atom; each R18 is a C1-C20 hydrocarbyl radical optionally containing one or more heteroatoms belonging to groups 14-16; each R4 is a hydrogen atom or a C1-6-hydrocarbyl radical; each W is a 5 or 6 membered aryl or heteroaryl ring wherein each atom of said ring is optionally substituted with at least one R5 group; each R5 is the same or different and is a C1-C20 hydrocarbyl r

Abstract: A silicon-bridged Cp-Ar transition metal complex serves as a catalytic component capable of efficiently and highly selectively producing 1-hexene through trimerization reaction of ethylene. The transition metal complex is represented by formula (1): wherein M represents a transition metal atom of Group 4 of the Periodic Table of the Elements; X1, X2, X3, R1, R2, R3, R4, R5, R6, R7, R8, and R9 each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, and an aralkyloxy group having 7 to 20 carbon atoms, and wherein each of the groups may have a halogen atom as a substituent.

Abstract: The present invention provides methods of making stereo-enriched ansa-metallocene compounds using an unchelated amine compound. Generally, these methods result in a rac:meso isomer selectivity of the stereo-enriched ansa-metallocene compound of greater than 4:1.

Abstract: The present invention relates to new (triorganosilyl)alkynes and their derivatives having general formula 1 R1—C?C—Z (I) In its second aspect, this invention relates to a new selective method for the preparation of new and conventional (triorganosilyl)alkynes and their derivatives having the general formula 1, by the silylative coupling of terminal alkynes with halogenotriorganosilanes in the presence of an iridium catalyst and a tertiary amine.

Abstract: The invention relates to platinum complexes, to a method for preparing the same and to the use thereof for the chemical vapor deposition of metal platinum. The chemical vapor deposition of platinum onto a substrate is made from a platinum organo-metal compound the includes a ligand with a cyclic structure including at least two non-adjacent C?C double bonds, and the platinum organo-metal compound has a square-lane structure in which the platinum is bonded to each of the C?C double bonds of the ligand, thereby forming a (C?C)—Pt—(C?C) of 60° to 70°.

Abstract: An ?-olefin polymer has (A) a tacticity index(meso triad fraction)[mm] of 10 to 50 mol %, (B) a kinematic viscosity at 100° C. of 200 to 10,000 mm2/s, (C) a content of a dimer and a trimer is less than 2 mass %, and (D) an average number of carbon atoms of 4 to 30.

Abstract: Novel trihydridosilyl-terminated polysilanes and methods for their synthesis, which are applicable to other polysilanes, are provided. The synthetic methods provide for facile preparation of products with minimal handling of pyrophoric intermediates and byproducts. The novel compounds contain at least three silicon-silicon bonds and at least one terminal silicon atom having three hydrogen substituents.

Abstract: A complex of formula (I): wherein M is zirconium or hafnium; each X is a sigma ligand; L is a divalent bridge selected from —R?2C—, —R?2C—CR?2—, —R?2Si—, —R?2Si—SiR?2—, —R?2Ge—, wherein each R? is independently a hydrogen atom, C1-C20-hydrocarbyl, tri(C1-C20-alkyl)silyl, C6-C20-aryl, C7-C20-arylalkyl or C7-C20-alkylaryl; each R1 is a C4-C20 hydrocarbyl radical branched at the ?-atom to the cyclopentadienyl ring, optionally containing one or more heteroatoms belonging to groups 14-16, or is a C3-C20 hydrocarbyl radical branched at the ?-atom to the cyclopentadienyl ring where the ?-atom is an Si-atom; n is 0-3; each R18 is the same or different and may be a C1-C20 hydrocarbyl radical optionally containing one or more heteroatoms belonging to groups 14-16; each R4 is a hydrogen atom or a C1-6-hydrocarbyl radical; each W is a 5 or 6 membered aryl or heteroaryl ring wherein each atom of said ring is optionally substituted with an R5 group each R5 is the same or different and is a C1-C20 hydrocarbyl radical option

Abstract: The present invention relates to a new transition metal compound based on cyclopenta[b]fluorenyl group, a transition metal catalyst composition containing the same and having high catalytic activity for preparing an ethylene homopolymer or a copolymer of ethylene and one ?-olefin, a method of preparing an ethylene homopolymer or a copolymer of ethylene and ?-olefin using the same, and the prepared ethylene homopolymer or the copolymer of ethylene and ?-olefin.

Abstract: A catalyst system comprising a half-sandwich chromium complex, an activator support and an optional cocatalyst. A compound of formula Cp?Cr(Cl)2(Ln), where Cp? is ?5—C5H4CH2CH2CH?CH2 and Ln is pyridine, THF or diethylether. A compound of formula Cp?Cr(Cl)2(Ln), where Cp? is ?5—C5H4C(Me)2CH2CH2CH?CH2 and Ln is pyridine, THF or diethylether.

Abstract: Borohydride metallocene complex of lanthanide, preparation process, catalytic system incorporating borohydride metallocene complex, process for copolymerization of olefins employing catalytic system. The complex corresponds to one or other of formulae A and B: where, in A, two ligands Cp1, Cp2, each composed of a cyclopentadienyl group, are connected to the lanthanide Ln, such as Nd, and where, in B, a ligand molecule, composed of two cyclopentadienyl groups Cp1, Cp2 connected to one another via a bridge P of formula MR1R2, M is an element from group IVa, and R1 and R2, which are identical or different, represent an alkyl group comprising from 1 to 20 carbon atoms, is connected to the lanthanide Ln, L is alkali metal, N is molecule of a complexing solvent, x is integral or non-integral number?0, p is integer?than 1 and y is integer?0.

Abstract: The invention relates to compounds, in particular phosphinic ligands of metal complexes, as well as to metal complexes including said ligands and to supported catalysts including said metal complexes or said compounds. The invention also relates to methods for synthesizing said compounds, to complexes, and to supported catalysts, as well as to intermediate products used in said synthesis methods. The invention further relates to the uses of said compounds. The compounds of the invention are ferrocene compounds which have been functionalized so as to be capable of being heterogenized. The invention can be used in particular in the field of heterogeneous catalysis.

Abstract: A metallocene complex by which high uptake efficiency of ethylene and/or ?-olefin can be obtained compared with the conventional metallocene catalyst, and robber component having high molecular weight can be polymerized, and polymerization method of olefin. Metallocene complex (metallocene complex having furyl or thienyl group in which substituent exists at 5-position of indenyl ring, and substituent may exist at 2-position of indenyl ring, and the like) represented by the general formula [II], the catalyst for olefin polymerization characterized by comprising said metallocene complex, and polymerization method of olefin characterized that polymerization or copolymerization of olefin is carried out using said polymerization catalyst for olefin, and the like.

Abstract: Methods and compositions for depositing metal films are disclosed herein. In general, the disclosed methods utilize precursor compounds comprising gold, silver, or copper. More specifically, the disclosed precursor compounds utilize pentadienyl ligands coupled to a metal to increase thermal stability. Furthermore, methods of depositing copper, gold, or silver are disclosed in conjunction with use of other precursors to deposit metal films. The methods and compositions may be used in a variety of deposition processes.

Abstract: The present invention discloses catalyst compositions employing silicon-bridged metallocene compounds with bulky substituents. Methods for making these silicon-bridged metallocene compounds and for using such compounds in catalyst compositions for the polymerization of olefins also are provided.

Abstract: Provided is a homogeneous catalytic system for use in preparing an ethylene homopolymer or a copolymer of ethylene and ?-olefin, and more particularly a Group 4 transition metal compound in which a cyclopentadienyl derivative 3,4-positions of which are substituted with alkyls and an electron-donating substituent are crosslinked around a Group 4 transition metal. Also provided is a method of preparing an ethylene homopolymer or a copolymer of ethylene and ?-olefin, having high molecular weight, under high-temperature solution polymerization conditions using the catalytic system including such a transition metal compound and a co-catalyst composed of an aluminum compound, a boron compound or a mixture thereof. The catalyst according to present invention has high thermal stability and enables the incorporation of ?-olefin, and is thus effective in preparing an ethylene homopolymer or a copolymer of ethylene and ?-olefin, having various properties, in industrial polymerization processes.

Abstract: Certain metallocene compounds are provided that, when used as a component in a supported polymerization catalyst under industrially relevant polymerization conditions, afford high molar mass homo polymers or copolymers like polypropylene or propylene/ethylene copolymers without the need for any ?-branched substituent in either of the two available 2-positions of the indenyl ligands. The substituent in the 2-position of one indenyl ligand can be any radical comprising hydrogen, methyl, or any other C2-C40 hydrocarbon which is not branched in the ?-position, and the substituent in the 2-position of the other indenyl ligand can be any C4-C40 hydrocarbon radical with the proviso that this hydrocarbon radical is branched in the ?-position. This metallocene topology affords high melting point, very high molar mass homo polypropylene and very high molar mass propylene-based copolymers. The activity/productivity levels of catalysts including the metallocenes of the present invention are exceptionally high.