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Updated: Feb 7, 2026

Predicting Catalyst Extrudate Breakage Based on the Modulus of Rupture

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Published on: May 13, 2018

ピリジル基をベースとしたAl(iii)触媒を用いたアルケンおよびアルキンのオリゴメリゼーションと立体選択的重合

Dipanjana Choudhury¹, Richard Danylyuk¹, Alexandros Terzopoulos¹

¹Yusuf Hamied Department of Chemistry, University of Cambridge Lensfield Rd. Cambridge CB2 1EW UK oas23@cam.ac.uk jmg11@cam.ac.UK dsw1000@cam.ac.uk.

Chemical science

|February 6, 2026

Abstract:

Dealkylation of the dimers [R₂Al(2-py')]₂ (2-py' = 6-substituted pyridyl, R = Me, ⁱBu) with [Ph₃C][B(C₆F₅)₄] gives the putative cations [RAl(2-py')₂(µ-R)AlR]⁺ which can polymerise a range of alkenes with a high degree of stereoregularity (syndiotacticity in the case of polystyrene) and which cylotrimerise terminal alkynes to trisubstituted benzenes and a fulvene. This is the first report of stereoslective Al(iii) polymerisation and of the cyclotrimerisation of alkynes by static catalysis using a main group metal.

キーワード:

アルミニウム触媒立体選択的重合アルキン環三量化有機金属化学高分子化学

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The IUPAC naming system for alkenes replaces -an- with -en- in the corresponding parent alkanes. Accordingly, a simple alkene replaces the -ane suffix of the alkane with -ene.
As per the IUPAC rules, the longest carbon chain containing the maximum number of double bonds is identified as the parent chain and is numbered such that the doubly bonded carbon atoms receive the lowest possible numbers. The location of the double bond is indicated by the number of its first carbon atom. In branched...

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Alkenes like 1-butene and 2-butene exhibit constitutional isomerism, as they differ in the position of the double bond. Further, 2-butene exhibits stereoisomerism and exists as two distinct compounds differing in spatial arrangement.
An isomer is called cis-2-butene when the methyl groups are on the same side of the double bond, and the other stereoisomer, in which methyl groups are on the opposite side of the double bond, is called trans-2-butene. The cis and trans stereoisomers are not...