Acyloins or their enediol carbonates (vinylene carbonates) react with dibutyltin oxide or dibutyltin dimethoxide to give 2,2-dibutyl-1,3,2-dioxastannolens [e.g.(A)].[graphic omitted]
Catalyst components for the polymerization of olefins
申请人:BASELL POLIOLEFINE ITALIA S.R.L.
公开号:US10246532B2
公开(公告)日:2019-04-02
A solid catalyst component which exhibits high activity and stereospecificity in the polymerization of olefins made from or containing Mg, Ti and an electron donor of formula (I)
where R and R1 are selected from the group consisting of C1-C20 hydrocarbon groups, C6-C14 aryl or alkylaryl groups hydrocarbon groups, optionally containing a heteroatom selected from the group consisting of halogens, P, S, N, and O; R2 to R11 groups, equal to or different from each other, are hydrogen, halogen or C1-C15 hydrocarbon groups which can be optionally fused together to form one or more cycles with the proviso that R6 and R11 cannot join together to form a phenyl ring.
Highly reactive copper- and nickel mediated coupling of aroyl chlorides
作者:Tse Chong Wu、Reuben D. Rieke
DOI:10.1021/jo00245a053
日期:1988.5
Methylsulfinyl (Dimsyl) Anion as Umpolung Catalyst for the Chemoselective Cross-Benzoin Reaction of α-Diketones with Aldehydes
作者:Olga Bortolini、Giancarlo Fantin、Valeria Ferretti、Marco Fogagnolo、Pier Paolo Giovannini、Alessandro Massi、Salvatore Pacifico、Daniele Ragno
DOI:10.1002/adsc.201300652
日期:2013.11.11
AbstractThe hitherto unreported ability of the methylsulfinyl carbanion (dimsyl anion) to generate acyl anion equivalents is described. The dimsyl anion, in fact, efficiently catalyzes chemoselective intermolecular cross‐benzoin condensations of diaryl α‐diketones (benzils) with various aromatic and aliphatic aldehydes to give the corresponding aryl‐aryl and aryl‐alkyl benzoin benzoates in an atom‐economic fashion. The dimsyl anion acts as an environmentally friendly alternative to the toxic cyanide anion and it is obtained by in situ deprotonation of dimethyl sulfoxide (DMSO) solvent with a catalytic amount of a strong base, potassium tert‐butoxide (t‐BuOK) the optimal promoter. The assumption that the methylsulfinyl carbanion is the active catalyst in the title transformation is supported by electrospray ionization mass spectrometry (ESI‐MS) experiments.magnified image