3141-02-4

Upstream product

• 542-92-7 cyclopenta-1,3-diene 
• 78-93-3 butanone 
• 123-75-1 pyrrolidine 

Downstream Products

• 126752-06-5 TiCl₂(C₅H₄C(CH₃)(C₂H₅)C₆H₅)(C₅H₄CH₂CH(CH₂)3O) 
• 201300-28-9 TiCl₂(C₅H₅)(C₅H₄C(CH₃)(C₂H₅)C₆H₄OCH₃) 
• 191487-72-6 TiCl₂(C₅H₄C(CH₃)(C₂H₅)C₆H₄OCH₃)2 

Relevant academic research and scientific papers

A vinylcyclobutane substrate designed as a cyclopropylcarbinyl radical probe

Appending a spirocyclopropane linkage to bicyclo[3.2.0]hept-2-ene is achieved by selective kinetic cyclopropanation of 6-methylenebicyclo[3.2.0]hept- 2-ene. The resultant vinylcyclobutane undergoes [1,3] migration as the dominant thermal process. A minor cyclopropylcarbinyl (CPC) rearrangement product clearly implicates a diradical transition structure. The presence and absence of other potential thermal products have enabled us to construct a detailed mechanistic proposal to account for all viable dynamic processes. The Royal Society of Chemistry 2013.

Regioselective Preparation of Vinylcyclopentadienes and Selected Cycloadditions

A variety of vinylcyclopentadienes have been prepared by deprotonation of fulvenes with LDA at -78 deg C and quenching with acid at 0 deg C.The compounds were present as a mixture of valence tautomers, the 1-substituted isomer dominating over the 2-substituted isomer by a ratio of 2:1.In all instances the regioisomer with the 1,1-disubstituted ethylene side chain was formed.No isomer with a trisubsitituted exocyclic double bond was discernible by NMR.Fulvenes are thermodynamically more stable than the less highly substituted vinylcyclopentadienes.Thus, on contact with base vinylcyclopentadienes rearrange to fulvenes.Vinylcyclopentadienes react with acetylenedicarboxylic acid dimethyl ester to give Diels-Alder adducts, e.g., 7a and also bis adduct 8a.Intramolecular Diels-Alder reactions of appropriately substituted vinylcyclopentadienes are feasible in a protic solvent such as 1,2-ethanediol on heating to 190 deg C.In this case, the isomerization of the substituted vinylcyclopentadiene to substituted fulvene is a side reaction only.

METALLOCENE COMPOUND, PROCESS FOR PRODUCING METALLOCENE COMPOUND, OLEFIN POLYMERIZATION CATALYST, PROCESS FOR PRODUCING POLYOLEFIN, AND POLYOLEFIN

The metallocene compound according to the invention and the olefin polymerization catalyst containing the compound are intended to produce a catalyst capable of preparing an isotactic polymer with a high polymerization activity. The metallocene compound contains a substituted cyclopentadienyl group and a (substituted) fluorenyl group and has a structure wherein these groups are bridged by a hydrocarbon group or the like. The process for preparing a metallocene compound according to the invention is intended to selectively prepare a specific metallocene compound so as not to produce an isomer, and in this process an intermediate product is synthesized by a specific method. The process for preparing a polyolefin according to the invention is intended to prepare a polyolefin having excellent impact resistance and transparency, and this process comprises homopolymerizing an α-olefin of 3 to 8 carbon atoms or copolymerizing an olefin of 3 to 8 carbon atoms and another α-olefin in the presence of an olefin polymerization catalyst containing the above-mentioned metallocene compound.

REACTION OF DICYCLOPENTADIENYLYTTRIUM CHLORIDE WITH ALDEHYDES AND KETONES. A NOVEL CLEAVAGE REACTION OF Cp-Y ?-BOND

Dicyclopentadienylyttrium chloride reacts with aldehydes and ketones at 80 deg C in DME, generating fulvenes in excellent yields, while at lower temperature affording, after hydrolysis, cyclopentadienyl substituted alcohols.