A wide array of forms of palladium has been utilized as precatalysts for Heck and Suzuki coupling reactions over the last 15 years. Historically, nearly every form of palladium used has been described as the active catalytic species. However, recent research has begun to shed light on the in situ transformations that many palladium precatalysts undergo during and before the catalytic reaction, and there are now many suggestions in the literature that narrow the scope of types of palladium that may be considered true “catalysts” in these coupling reactions. In this work, for each type of precatalyst, the recent literature is summarized and the type(s) of palladium that are proposed to be truly active are enumerated. All forms of palladium, including discrete soluble palladium complexes, solid-supported metal ligand complexes, supported palladium nano- and macroparticles, soluble palladium nanoparticles, soluble ligand-free palladium, and palladium-exchanged oxides are considered and reviewed here. A considerable focus is placed on solid precatalysts and on evidence for and against catalysis by solid surfaces vs. soluble species when starting with various precatalysts. The review closes with a critical overview of various control experiments or tests that have been used by authors to assess the homogeneity or heterogeneity of catalyst systems.

On the Nature of the Active Species in Palladium Catalyzed Mizoroki–Heck and Suzuki–Miyaura Couplings – Homogeneous or Heterogeneous Catalysis, A Critical Review

1 Review 1.1 Overview 1.2 Solid-phase organic synthesis (SPOS) 1.3 Beyond conventional solid-phase organic synthesis 1.4 The review 1.5 Some definitions 1.6 Solid-supported reagents and scavengers 1.7 Multi-step use of solid-supported reagents and scavenging reagents 1.8 Conclusions and future perspective 2 Introduction to the tables 2.1 Organisation of tables (reagent and catalyst section) 2.2 Representative data entry (reagent and catalyst section) 2.3 Organisation of tables (scavenging agents section) 2.4 Representative data entry (scavenging agents section) 3 Tables of reagents and catalysts 4 Tables of scavengers 5 Other relevant reviews 5.1 Insoluble polymers 5.1.1 Structure and physical properties (insoluble polymers) 5.1.2 General (insoluble polymers) 5.1.3 Reactions (insoluble polymers) 5.1.4 Miscellaneous (insoluble polymers) 5.2 Soluble polymers 5.2.1 General (soluble polymers) 5.2.2 Reactions (soluble polymers) 5.3 Inorganic solids 5.3.1 Structure and physical properties (inorganic solids) 5.3.2 General (inorganic solids) 5.3.3 Reactions (inorganic solids) 5.3.4 Miscellaneous (inorganic solids) 5.4 Miscellaneous supports 5.4.1 Structure and physical properties (miscellaneous supports) 5.4.2 General (miscellaneous supports) 5.4.3 Reactions (miscellaneous supports) 5.4.4 Miscellaneous (miscellaneous supports) 5.5 Purification strategies 5.5.1 Various supports (purification strategies) 5.5.2 Insoluble polymers (purification strategies) 6 Acknowledgements 7 Abbreviations 8 References 1 Review

Multi-step organic synthesis using solid-supported reagents and scavengers: a new paradigm in chemical library generation

http://www.uwindsor.ca/users/j/jlichaa/reference.nsf/0/10ff8b04ff3a317885256d88005720f6/$FILE/tet-2005-61-11771%20Heck%20non%20conv.pdf

Non-conventional methodologies for transition-metal catalysed carbon–carbon coupling: a critical overview. Part 2: The Suzuki reaction

This review is devoted to the application of palladium metal catalysts to the Heck reaction (arylation or vinylation of alkenes with aryl or vinyl halides and pseudohalides). The number of relevant articles published in recent years shows steadily increasing interest in this field. A brief outline of the historical development of heterogeneous catalysis as applied to the Heck reaction is given (Section 2). Both supported metal catalysts (Section 3) and stabilized colloidal palladium catalysts (Section 4) are included. Heterogeneous catalysts supported over different kinds of supports (carbon, inorganic oxides, molecular sieves, polymeric materials, etc.) are reviewed under separate headings. Particular attention is paid to the metal leaching and the nature of catalysis, two tightly connected problems which appear to be still controversial (Section 5). Some perspectives are shortly discussed in the final section (Section 6).

Palladium metal catalysts in Heck CC coupling reactions

Development of simple and reliable protocols for the immobilization of catalytically active metal nanoparticles is an important aspect of the nanomaterials field. Amine groups bind very strongly to platinum and palladium nanoparticles; therefore, we have attempted to entrap aqueous platinum and palladium nanoparticles on the surface of micron-sized zeolite particles functionalized with amine groups. In this paper, we demonstrate that platinum and palladium nanoparticles bound at high surface coverage on 3-aminopropyltrimethoxysilane (APTS)-functionalized Na−Y zeolites are excellent heterogeneous catalysts for hydrogenation and Heck reactions. The assembly of platinum or palladium nanoparticles on the zeolite surface occurs via an interaction with the amine groups present in APTS leading to a new class of catalyst. The synthesized catalysts were well-characterized by UV−vis, FTIR, TGA, XRD, XPS, and TEM. TEM images of the fresh and used catalysts indeed show that the platinum and palladium nanoparticles su...

Pt and Pd Nanoparticles Immobilized on Amine-Functionalized Zeolite: Excellent Catalysts for Hydrogenation and Heck Reactions

Several arylacetaldehydes 5 were synthesized in moderate yields via Heck reaction of acrylamide (1) with substituted iodobenzenes 2 in the presence of the polymeric catalyst P-phenyl-(1,10-phenanthroline)-palladium(O) [P-ph-phen.Pd(O)] followed by Hofmann reaction and subsequent hydrolysis

Kao Tsi-yu

Papers

A Facile Approach to Arylacetaldehydes via Polymeric Palladium Catalyst

A Facile Approach to 2-Arylethylamines Via Polymeric Palladium Catalyst

[Poly(styryl)phenanthroline]palladium as heterogeneous catalyst for heck arylation using iodobenzene

[Poly(styryl)phenanthroline]palladium catalyst. Synthesis and some of its applications in vinylic substitution reactions with organic halides