Sequence-regulated vinyl polymers via iterative atom transfer radical additions and acyclic diene metathesis polymerization

Iterative ATRAs and ADMET polymerization enabled the synthesis of sequence-regulated vinyl polymers without statistical distribution of monomer compositions and sequences.

Main-Chain Ferrocene-Containing Polymers Prepared by Acyclic Diene Metathesis Polymerization: A Review

Ferrocene, the crown of metallocene family, is widely studied as a functional unit in electrochemical and catalytic applications due to its sandwich structure. Ferrocene moieties can be embedded into the polymer backbone, leading to main-chain ferrocenecontaining polymers. These polymeric materials combine the unique functionalities of iron center with the processabilities of polymers. As one of the choice polymerization techniques, acyclic diene metathesis (ADMET) polymerization serves as a versatile method to prepare main-chain ferrocene-containing polymers under mild conditions using α,ω-dienes as monomers. This paper overviews main-chain ferrocene-containing polymers prepared by ADMET polymerization. Advances in the design, synthesis and applications of this class of organometallic monomers and polymers are detailed.

ADMET Polymerization of Dimeric Cinchona Squaramides for the Preparation of a Highly Enantioselective Polymeric Organocatalyst

Under the acyclic diene metathesis (ADMET) reaction condition, the C3-vinyl groups of cinchona alkaloids readily react with each other to form a C-C bond. A novel type of cinchona alkaloid polymers was synthesized from dimeric cinchona squaramides using the Hoveyda-Grubbs’ second-generation catalysts (HG2) by means of ADMET reaction. The chiral polymers, containing cinchona squaramide moieties in their main chains, were subsequently employed as catalysts for the enantioselective Michael reaction to give the corresponding chiral adducts in high yields with excellent enantioselectivity and diastereoselectivity. Both enantiomers from the asymmetric Michael reaction were distinctively prepared while using the polymeric catalysts, possessing pseudoenantiomeric structures. The catalysts were readily recovered from the reaction mixture and recycled several times due to the insolubility of the cinchona-based squaramide polymers.