P-Chiral Phosphine–Sulfonate/Palladium-Catalyzed Asymmetric Copolymerization of Vinyl Acetate with Carbon Monoxide

Abstract

Utilization of palladium catalysts bearing a P-chiral phosphine-sulfonate ligand enabled asymmetric copolymerization of vinyl acetate with carbon monoxide. The obtained γ-polyketones have head-to-tail and isotactic polymer structures. The origin of the regio- and stereoregularities was elucidated by stoichiometric reactions of acylpalladium complexes with vinyl acetate. The present report for the first time demonstrates successful asymmetric coordination-insertion (co)polymerization of vinyl acetate.

Ruthenium‐Containing Phosphinesulfonate Chelate for the Hydrogenation of Aryl Ketones

“…However, examples of enantiopure phosphinesulfonate chelates are scarce in the literature. Last year, Nozaki and co‐workers reported the application of P‐chiral phosphinesulfonates in palladium‐catalyzed copolymerization reactions, but the access to these phosphines required preparative chiral HPLC 20e. On the other hand, binaphthophosphepine,34, 35 which was synthesized from binaphthol, has shown interesting activities in the enantioselective hydrogenation of functionalized β‐ketoesters 34d.…”

Ligand-controlled insertion regioselectivity accelerates copolymerisation of ethylene with methyl acrylate by cationic bisphosphine monoxide–palladium catalysts

“… 7 The same preferential 2,1-insertion of MA has been observed in the case of palladium/phosphine-sulfonate catalysts. 9 , 10 As an exception, selective 1,2-insertion of MA was reported with a [P–SO 3 ]–type ligand bearing a bulky diazaphospholidine group, 6 although the catalyst did not promote ethylene/MA copolymerisation. 6 b Recently, ethylene/MA cooligomerization by palladium/phosphine-phosphonate catalysts was reported, in which chain-end analysis suggested coexistence of 2,1- and 1,2-insertion of MA.…”

Crystal structure of zwitterionic 2-[bis(2-methoxyphenyl)phosphaniumyl]-4-methylbenzenesulfonate monohydrate dichloromethane monosolvate

“…Incorporation of additional potential donor groups within the phosphane structure provides added versatility to such ligands. For example, ortho-phosphanylbenzenesulfonate (PO) ligands, such as 2-[bis(2-methoxyphenyl)phosphanyl]benzenesulfonate, bind to Pd II in a 2 P,O mode to form (PO)PdR species that are active for the polymerization of ethylene (Cai et al, 2012;Contrella & Jordan, 2014;Zhou et al, 2014), copolymerization of ethylene and polar monomers (Drent et al, 2002a;Nakamura et al, 2013), non-alternating copolymerization of ethylene and CO (Drent et al, 2002b), and alternating copolymerization of CO with polar monomers (Nakamura et al, 2011(Nakamura et al, , 2012. Phosphanylarenesulfonate ligands derived from para-toluenesulfonic acid are useful because the extra methyl group provides a convenient NMR handle for characterizing complexes and monitoring reactions.…”