Syndiospezifische polymerisation von propylen: 3-, 4-, 3,4- und 4,5-substituierte zirkonocenkomplexe des typs (C13H8−nRnCR′2C5H4)ZrCl2 (n = 1,2; R Alkyl, Aryl; R′ Me, Ph)
摘要:
Substituents in the positions 3, 4, 5 and 6 of the fluorenylidene fragment clearly influence the polymerization behaviour of the syndiospecific catalyst systems (C(13)H(8-n)R(n)CR(2)'C5H4)ZrCl2/MAO (n = 1, 2; R = alkyl, aryl; R' = Me, Ph). We report seven new catalyst precursors of this type, including first polymerization results. An X-ray study of the 4,5-dimethyl derivative 10b explains the reduced activity and stereospecifity of this catalyst.
Syndiospezifische polymerisation von propylen: 3-, 4-, 3,4- und 4,5-substituierte zirkonocenkomplexe des typs (C13H8−nRnCR′2C5H4)ZrCl2 (n = 1,2; R Alkyl, Aryl; R′ Me, Ph)
摘要:
Substituents in the positions 3, 4, 5 and 6 of the fluorenylidene fragment clearly influence the polymerization behaviour of the syndiospecific catalyst systems (C(13)H(8-n)R(n)CR(2)'C5H4)ZrCl2/MAO (n = 1, 2; R = alkyl, aryl; R' = Me, Ph). We report seven new catalyst precursors of this type, including first polymerization results. An X-ray study of the 4,5-dimethyl derivative 10b explains the reduced activity and stereospecifity of this catalyst.
One-Pot Palladium(II)-Catalyzed Synthesis of Fluorenones via Decarboxylative Cyclization
作者:Zhiqiang Cai、Xu Hou、Ling Hou、Zhiquan Hu、Bo Zhang、Zhengsheng Jin
DOI:10.1055/s-0035-1560527
日期:——
A one-pot palladium-catalyzed synthesis of fluoronones via decarboxylative cyclization is reported. This protocol offers good yields and tolerates a broad range of functional groups. Based on the extensive experimental data, we propose a plausible decarboxylative insertion mechanism.