Oligo- and polymerization of phospha [2]ferrocenophanes to one dimensional phosphorus chains with ferrocenylene handles. (1st March 2022)

• Record Type: Journal Article
• Authors: Dey, Subhayan; Kargin, Denis; Höfler, Mark V.; Szathmári, Balázs; Bruhn, Clemens; Gutmann, Torsten; Kelemen, Zsolt; Pietschnig, Rudolf
• Is Part Of: Polymer. Volume 242(2022)
• Publication Date: 2022-03-01
• Subjects: Ansa-ferrocene -- DFT calculations -- Oligophosphine -- Polyphosphane -- Ring-opening polymerization -- Solid-state NMR; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2022.124589
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: A lithium halide exchange reaction at low-temperature, via the treatment of 2, 6-di(isopropyl)phenyllithium on 1, 1′-bis-(dichlorophosphino)ferrocene, resulted in the first isolated example of an aryl-substituted diphospha [2]ferrocenophane (diphospha [2]FCP) 2 . Although compound 2 did not show any recognizable thermal reaction at higher temperature (up to 350 °C), its tert -butyl-substituted counterpart 1 underwent a clean selective heat-mediated P–C cleavage reaction, followed by an inter-molecular rearrangement, to produce a P–P fused bis [3]ferrocenophane 3 with all- trans oriented P-chain, which upon further heating gave a polyferrocenylphosphane t Bu-[Fc'P2 ]n - t Bu (4 ). Since polymer 4 is insoluble in common organic solvents, it has been characterized with solid-state techniques, including solid-state NMR. Density functional theory (DFT) has further been employed to identify possible pathways for P–C bond cleavage on 1 and 2, as well as to evaluate accessible pathways for further polymerization toward 4 . Graphical abstract: Image 1 Highlights: A new sterically challenged diphospha [2]ferrocenophane has been prepared. tert -Butyl diphospha [2]ferrocenophane undergoes oligo-/polymerization via C–P activation. The all- trans linear arrangement of the phosphorus chain in an oligomer has been demonstrated by single crystal XRD.