Hafnocene dichloride

To find more information about the influence of steric effects on the polymerization performance, catalyst 2 (5,6 triptycene indenyl hafnocene dichloride) was developed. 

Since plastomeric polypropylenes were insufficiently investigated, further improvement of catalyst activity correlated with an easy synthetic approach was required. Therefore, the two asymmetric hafnocene dichloride complexes, each bearing a 2,5,7- and 2,4,6-trimethyl substituted indenyl moiety (4a, 4b) were developed. 

Cell proliferation and benign local tumors occurred in mice given a single intradermal injection of hafiiium oxychloride. Hafnocene dichloride induced DNA adducts when incubated with mammalian DNA. ... 

Fluorenyl- /-fluorenyl complexes, with Ti(IV), 4, 406 Fluorenyl hafnocene dichlorides, synthesis, 4, 943 Fluorenyl zirconocene dichlorides, synthesis, 4, 943 Fluorescence resonance energy transfer, in high-throughput catalyst discovery, 1, 358 Fluorescent sensors, Pt acetylenes as, 12, 472... 

Matsumoto, T, Katsuki, M, Jona, H, Suzuki, K, Synthetic study toward vineomycins. Synthesis of C-aryl glycoside sector via hafnocene dichloride-silver perchlorate-promoted tactics. Tetrahedron Lett., 30, 6185-6188, 1989. 

The direct linkage of phenolic aromatic rings in the presence of hafnocene dichloride-silver perchlorate as a promoter has been described in the synthesis of gilvocarcin M and V [ 168,295,296]. 

So far, the only examples of O-C migrations have applied to pyranose sugars or derivatives thereof. However, it should be noted that such reactions are applicable to furanose sugars. One particular example, reported by Matsumoto, et al.,101 was used in the total synthesis of gilvocarcin M. The specific reaction, shown in Scheme 2.4.25, utilized the acetoxy activated furanoside shown. Treating this compound with the phenol and using the hafnocene dichloride-silver perchlorate complex as the Lewis acid, the desired C-arylglycoside was obtained in 87% yield with the a anomer favored in a ratio of 8 1. 

Summary A number of differently substituted mono- and dianionic oligosilyl compounds have been reacted with zirconocene and hafnocene dichloride to give mono and bissilylated metallocenes. The use of a TMEDA adduct of tris(trimethylsilyl)silyl potassium enables the formation of a Cp-free hafnium silyl compound. 

Zirconocene dichloridejsilver perchlorate Hafnocene dichloride j silver perchlorate P-Glycosides from p-glycosyl fluorides Solvent effect on stereoselectivity... 

Hafnocene dichloride 44, 191, 802 Halides (s.a. under Replacement) - as reagent 43, 269... 

Zirconocene dichloride j silver perchlorate Hafnocene dichloride j silver perchlorate C-Aryl glycosides from glycosyl fluorides Stereospecifle conversion... 

The silabridged hafnocene dichlorides Hf(tt-C3H4(SiMe2)B n = 1-3 were prepared from Cl(Me2Si)aCl in sequential reactions with NaCp, BuLi and Doubly bridged C2... 

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