105333-10-6Relevant articles and documents
Pd(η3-1-PhC3H4)(η5- C5H5), an unusually effective catalyst precursor for Suzuki-Miyaura cross-coupling reactions catalyzed by bis-phosphine palladium(0) compounds
Fraser, Andrew W.,Besaw, Jessica E.,Hull, Laura E.,Baird, Michael C.
, p. 2470 - 2475 (2012)
It has previously been shown that the easily handled, heat- and air-stable compound Pd(η3-1-PhC3H4)(η5- C5H5) (Vb) reacts rapidly with a wide variety of tertiary phosphines L to produce near-quantitative yields of the corresponding Pd(0) compounds PdL2, which are widely believed to be the active species in many often-used cross-coupling catalyst systems based on Pd(PPh 3)4 (I), Pd2(dba)3 (II), PdCl 2 (III), and Pd(OAc)2 (IV). However, catalyst precursors I-IV are in fact known to preferentially generate sterically hindered, three-coordinate Pd(0) species rather than two-coordinate PdL2, and thus Vb is hypothetically expected to be a better catalyst precursor for e.g. Suzuki-Miyaura cross-coupling reactions. Utilizing the conventional Suzuki-Miyaura cross-coupling reaction of phenylboronic acid with bromoanisole, comparisons are made of the efficacies of catalyst systems based on Vb with those based on compounds I-IV (L = the representative phosphines PPh 3, PCy3, PBut3). As anticipated, catalysts generated from Vb are significantly more competent and, as a bonus, Vb makes palladium(0) complexes PdL2 available under rigorously anhydrous conditions.
Pd(η3-1-PhC3H4)(η5- C5H5), an unusually effective catalyst precursor for heck-mizoroki and sonogashira cross-coupling reactions catalyzed by bis-phosphine palladium(0) compounds
Fraser, Andrew W.,Jaksic, Bryan E.,Batcup, Rhys,Sarsons, Christopher D.,Woolman, Michael,Baird, Michael C.
supporting information, p. 9 - 11 (2013/03/13)
The compound Pd(η3-1-PhC3H4) (η5-C5H5) reacts essentially quantitatively with a variety of phosphines L to form cross-coupling catalysts of the type PdL2 and has recently been shown to be a much more effective catalyst precursor for Suzuki-Miyaura cross-coupling reactions in comparison to more commonly utilized precursors such as Pd(PPh3)4, Pd 2(dba)3, and Pd(OAc)2, which do not effectively generate two-coordinate species PdL2. This advantage is expected to apply also to e.g. Heck-Mizoroki and Sonogashira cross-coupling reactions, both of which are generally believed to be catalyzed by species of the type PdL 2. Therefore, comparisons of the efficacies of catalyst systems based on Pd(η3-1-PhC3H4)(η5- C5H5), Pd(PPh3)4, Pd 2(dba)3, and Pd(OAc)2 are made utilizing the conventional coupling reactions of aryl halides with methyl acrylate and styrene for Heck-Mizoroki coupling and with phenylacetylene for Sonogashira coupling. As anticipated, catalyst systems based on Pd(η3-1-PhC 3H4)(η5-C5H5) are found to be significantly more active.