‘Sacrificial’ Supramolecular Assembly and Pressure-Induced Polymerization: Toward Sequence-Defined Functionalized Nanothreads

<div><div><div><p>Limited supramolecular strategies have been utilized to synthesize sequence-defined polymers, despite the high utility of noncovalent interactions in materials design. Herein, we illustrate the utility of ‘sacrificial’ aryl-perfluoroaryl supramolecular synthons to synthesize sp3-hybridized nanothreads from sp2-enriched reactants. Our strategy features A-B reactant pairs in the form a phenol:pentafluorophenol co-crystal that is preorganized for an electronically-biased sequence-defined polymerization. The polymerization, initiated at 12 GPa, affords an alternating copolymer featuring exogenous –OH functionalities. The nanothread polymer exhibits crystallinity, as evidenced by a hexagonal X-ray diffraction pattern. The presence of the external substitution is confirmed through IR and Raman spectroscopy. Our approach realizes the first example of a functionalized sequence-defined nanothread through sacrificial supramolecular preorganization and presents a further approach for de novo design of complex nanothreads.</p></div></div></div>

‘Sacrificial’ Supramolecular Assembly and Pressure-Induced Polymerization: Toward Sequence-Defined Functionalized Nanothreads

<div><div><div><p>Limited supramolecular strategies have been utilized to synthesize sequence-defined polymers, despite the high utility of noncovalent interactions in materials design. Herein, we illustrate the utility of ‘sacrificial’ aryl-perfluoroaryl supramolecular synthons to synthesize sp3-hybridized nanothreads from sp2-enriched reactants. Our strategy features A-B reactant pairs in the form a phenol:pentafluorophenol co-crystal that is preorganized for an electronically-biased sequence-defined polymerization. The polymerization, initiated at 12 GPa, affords an alternating copolymer featuring exogenous –OH functionalities. The nanothread polymer exhibits crystallinity, as evidenced by a hexagonal X-ray diffraction pattern. The presence of the external substitution is confirmed through IR and Raman spectroscopy. Our approach realizes the first example of a functionalized sequence-defined nanothread through sacrificial supramolecular preorganization and presents a further approach for de novo design of complex nanothreads.</p></div></div></div>

Sequence-directed dynamic covalent assembly of base-4-encoded oligomers

Molecular ladders and molecular grids were self-assembled employing two orthogonal dynamic covalent reactant pairs in an aqueous environment.

Microwave-assisted synthesis of (aminomethylene)bisphosphine oxides and (aminomethylene)bisphosphonates by a three-component condensation

A practical method was elaborated for the synthesis of (aminomethylene)bisphosphine oxides comprising the catalyst- and solvent-free microwave-assisted three-component condensation of primary amines, triethyl orthoformate and two equivalents of diphenylphosphine oxide. The method is also suitable for the preparation of (aminomethylene)bisphosphonates using (MeO)2P(O)H/(MeO)3CH or (EtO)2P(O)H/(EtO)3CH reactant pairs and even secondary amines. Several intermediates referring to the reaction mechanism together with a few by-products could also be identified.