Rapid One‐Step Synthesis of Complex‐Architecture Block Polymers Using Inductively “Armed–Disarmed” Monomer Pairs

Abstract

A facile method is reported for rapid, room-temperature synthesis of block copolymers (BCP) of complex morphology and hence nontraditional spherical assembly. The use of solvated electrons generates radical anions on olefinic monomers, and with a felicitous choice of monomer pairs, this species will propagate bimechanistically (via radical and the anion) to form BCPs. Molecular weight of the obtained BCP range from M = 97 000-404 000 g mol (polydispersity index, PDI = 1.4-3.0) depending on monomer pairs. The composition of the blocks can be controlled by changing monomer ratio, with the caveat that yield is affected. Detailed characterization by 2D nuclear magnetic resonance spectroscopy, differential scanning calorimetry (DSC), and analysis of the mechanisms involved indicate the structure of obtained block copolymers to be at least a triblock with a complex central unit. Evaluating trends in the Hammett parameter segregates monomer pairs into "armed and disarmed" groups with respect to radical or anionic polymerization akin to oligosaccharides synthesis.

Birch Reduction of Aromatic Compounds by Inorganic Electride [Ca2N]+•e– in an Alcoholic Solvent: An Analogue of Solvated Electrons

“…The yield for the electron-withdrawing group (EWG) ( 2d ) was higher than that for the electron-donating groups (EDG) ( 2e – 2f ). This result is probably attributed to the stabilization of carbanion by the inductive effect . In the case of 9-chloromethylanthracene and 9-bromoanthracene ( 2c – 2d ), hydrodehalogenation and dearomatization reactions occurred simultaneously.…”

“…This result is probably attributed to the stabilization of carbanion by the inductive effect. 39 In the case of 9-chloromethylanthracene and 9-bromoanthracene (2c−2d), hydrodehalogenation and dearomatization reactions occurred simultaneously. In sequence, we explored the Birch reduction of tetracyclic aromatic hydrocarbons (2g−2h).…”

Diaziridyl Ether of Bisphenol A

“…These attractive features provide molecular insight into the potential utility of aziridines for developing novel curing resins and for overcoming the limitations of conventional epoxy. Furthermore, we envision that the chemoselectivity of resins demonstrated here would bring benefit to the design of heterogeneous resin scaffold for advanced polymeric systems …”

“…Furthermore, we envision that the chemoselectivity of resins demonstrated here would bring benefit to the design of heterogeneous resin scaffold for advanced polymeric systems. 40…”