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Jacob L Irwin

Publications and source records attributed to Jacob L Irwin.

4 recordsLinked to original sources

Synthesis of neoglycopolymers by a combination of "click chemistry" and living radical polymerization.

The synthesis of novel well-defined alkyne side chain functional polymers featuring narrow molecular weight distributions (PDI = 1.09-1.17) by living radical polymerization is described. Grafting of protected and unprotected carbohydrates is achieved via either a C-6 or an anomeric azide (alpha or beta) onto these polymers by Cu(I)-catalyzed "click chemistry", providing a simple and efficient route to synthetic glycopolymers. The strategy provides an extremely powerful tool for the synthesis of libraries of materials that differ only in the nature of the sugar moiety presented on a well-defined polymer scaffold. A library of multivalent ligands were then prepared following a "coclicking" synthetic protocol, and the reactivity of these glycopolymers in the presence of concanavalin A and Ricinus communis agglutinin, model lectins able to selectively bind appropriate mannose and galactose derivatives, respectively, was assessed.

Journal Article↗

Superbowl container molecules.

The design, chemical synthesis, guest binding, and self-assembly of tureen-shaped container molecules is presented. With a large noncollapsible interior and five external binding sites, each superbowl container host is shown to bind up to nine guest molecules in well-defined locations.

Calixarenes↗

Amination of ethers using chloramine-T hydrate and a copper(I) catalyst.

Amination of C-H bonds activated by ether oxygen atoms is facile with chloramine-T as nitrene source and copper(I) chloride in acetonitrile as catalyst. For cyclic ethers the hemiaminal products are generally stable and can be isolated pure. For acyclic ethers, the hemiaminal products, as expected, fragment with elimination of alcohol to yield imines. When activation of benzylic positions is remote through a conjugated system, stable benzylamine derivatives are isolated. Mechanistic studies are consistent with concerted insertion of an electrophilic nitrenoid into the C-H bond in the rate-determining step, though in an asynchronous manner with a more activated substrate.

Amination↗

Chiral biscavitand propellers: synthesis, conformations and multiple guest binding.

[structure: see text]. The synthesis and properties of molecules containing two cavitand bowls, with interbowl linkages comprising one carbon atom at various oxidation levels, are reported. A carbonyl-bridged biscavitand binds three CH2Cl2 molecules in the solid state through a helical conformation. Evidence for the same chiral conformation in the solution phase is presented.

Journal Article↗