Development of Environmentally Friendly Atom Transfer Radical Polymerization

Atom transfer radical polymerization (ATRP) is one of the most successful techniques for the preparation of well-defined polymers with controllable molecular weights, narrow molecular weight distributions, specific macromolecular architectures, and precisely designed functionalities. ATRP usually involves transition-metal complex as catalyst. As the most commonly used copper complex catalyst is usually biologically toxic and environmentally unsafe, considerable interest has been focused on iron complex, enzyme, and metal-free catalysts owing to their low toxicity, inexpensive cost, commercial availability and environmental friendliness. This review aims to provide a comprehensive understanding of iron catalyst used in normal, reverse, AGET, ICAR, GAMA, and SARA ATRP, enzyme as well as metal-free catalyst mediated ATRP in the point of view of catalytic activity, initiation efficiency, and polymerization controllability. The principle of ATRP and the development of iron ligand are briefly discussed. The recent development of enzyme-mediated ATRP, the latest research progress on metal-free ATRP, and the application of metal-free ATRP in interdisciplinary areas are highlighted in sections. The prospects and challenges of these three ATRP techniques are also described in the review.

Porous Organic Polymer Supported Rhodium as a Reusable Heterogeneous Catalyst for Hydroformylation of Olefins

A new porous organic polymer has been prepared via copolymerization of divinyl-functionalized phosphoramidite ligand and tris(4-vinylphenyl)phosphine. The porous polymer was loaded with Rh(acac)CO₂ to yield a supported Rh catalyst, which demonstrated good regioselectivity ( l/ b = 6.7-52.8) and high catalytic activity (TON up to 45.3 × 10⁴) in hydroformylation of terminal and internal olefins. Remarkably, the heterogeneous catalyst can be reused at least 10 cycles without losing activity and selectivity in hydroformylation of 1-hexene.

Immobilized Pd(0) nanoparticles on phosphine-functionalized graphene as a highly active catalyst for Heck, Suzuki and N-arylation reactions

Phosphine functionalized graphene was used for the immobilization of Pd nanoparticles and utilized in C–C and C–N bond formation reactions.

Phosphanamine-functionalized magnetic nanoparticles (PAFMNP): an efficient magnetic recyclable ligand for the Pd-catalyzed Heck reaction of chloroarenes

The reaction of MNPs with a phosphanamine-functionalized trimethoxysilyl compound resulted in the production of a novel and efficient magnetic reusable ligand for application in the Heck reaction of aryl chlorides.