Components and catalysts for the polymerization of olefins
申请人:Gulevich Yuri
公开号:US20090118446A1
公开(公告)日:2009-05-07
The present invention relates to a solid catalyst component for the polymerization of olefins CH
2
═CHR in which R is hydrogen or a hydrocarbon radical with 1-12 carbon atoms, comprising Mg, Ti, halogen and an electron donor selected from γ-butyrolactone derivatives of a particular formula. Said catalyst components, when used in the polymerization of olefins and in particular of propylene, are capable to give polymers in high yields and with high isotactic index expressed in terms of high xylene insolubility.
A regio- and stereo-controlled synthesis of α,β-unsaturated carbonyl compounds
作者:Susumu Sato、Isamu Matsuda、Yusuke Izumi
DOI:10.1016/s0040-4039(00)98543-5
日期:——
rhodium(I) catalyzed isomerization of 1,3-diene monoepoxides and α-alkylidene-γ-butyrolactones, respectively. The former transformation is formally regarded as the equivalent of a regiospecific aldol condensation of an unsymmetricalketone.
New Methods for Stereoselective Synthesis of α-Alkylidene-γ-butyrolactones Using Monoanion of<i>O</i>-Ethyl<i>S</i>-(Tetrahydro-2-oxo-3-furanyl) Thiocarbonate and Dianion of α-Mercapto-γ-butyrolactone
The lithium enolates of O-ethyl S-(tetrahydro-2-oxo-3-furanyl) dithiocarbonate and thiocarbonate were found to be efficient reagents for the stereoselective synthesis of α-alkylidene-γ-butyrolactones fromcarbonylcompounds. The dianion of α-mercapto-γ-butyrolactone was successfully generated by treatment of α-mercapto-γ-butyrolactone with 2.2 equivalents of lithium diisopropylamide in the presence