Steric activation of chelate catalysts: efficient polyketone catalysts based on four-membered palladium (II) diphosphine chelates

SJ Dossett, A Gillon, AG Orpen, JS Fleming…

Index: Dossett; Gillon; Orpen; Fleming; Pringle; Wass; Jones Chemical Communications, 2001 , # 8 p. 699 - 700

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Citation Number: 70

Abstract

Polydispersities are consistently around the value of 2, as expected for a single site catalyst, and termonomer incorporation is largely unaffected by ligand structure. However, other aspects of the polymerisations are very sensitive to the structure of the ligand. Generally, polymerisation rate, catalyst stability and polymer molecular weight all increase with increasing steric bulk of the aryl ortho substituent (entries 1–6). These effects are very pronounced with the o- ...