17356-09-1Relevant articles and documents
Rapid access to (cycloalkyl)tellurophene oligomer mixtures and the first poly(3-aryltellurophene)
Luppi, Bruno T.,McDonald, Robert,Ferguson, Michael J.,Sang, Lingzi,Rivard, Eric
, p. 14218 - 14221 (2019)
Polytellurophenes represent an emerging class of π-conjugated polymers that possess important characteristics for flexible electronics, such as narrow HOMO-LUMO gaps (Eg) and charge mobilities that can be orders of magnitude larger than their ubiquitous polythiophene counterparts. Herein we use the reactivity of pinacolboronate (BPin) groups attached to tellurophene scaffolds to directly prepare new 2,5-diiodinated monomers, which are then polymerized to afford new low Eg oligomers and polymers. Specifically, mixtures of (cycloalkyl)tellurophene oligomers (of 5 to 12 repeat units) with ring-fused 5- and 6-membered cyclic side chains were prepared via Yamamoto coupling, with a dramatic narrowing of band gap noted when less bulky 5-membered cycloalkyl side groups were present, due to enhanced tellurophene ring coplanarity. Grignard metathesis (GRIM) was also used to gain access to the first poly(3-aryltellurophene) with 94% regioregularity, along with a low Eg of 1.3 eV and an onset of light absorption at ca. 1000 nm.
Olefin-Stabilized Cobalt Nanoparticles for C=C, C=O, and C=N Hydrogenations
Sandl, Sebastian,Schwarzhuber, Felix,P?llath, Simon,Zweck, Josef,Jacobi von Wangelin, Axel
supporting information, p. 3403 - 3407 (2018/02/13)
The development of cobalt catalysts that combine easy accessibility and high selectivity constitutes a promising approach to the replacement of noble-metal catalysts in hydrogenation reactions. This report introduces a user-friendly protocol that avoids complex ligands, hazardous reductants, special reaction conditions, and the formation of highly unstable pre-catalysts. Reduction of CoBr2 with LiEt3BH in the presence of alkenes led to the formation of hydrogenation catalysts that effected clean conversions of alkenes, carbonyls, imines, and heteroarenes at mild conditions (3 mol % cat., 2–10 bar H2, 20–80 °C). Poisoning studies and nanoparticle characterization by TEM, EDX, and DLS supported the notion of a heterotopic catalysis mechanism.
A practical and general ipso iodination of arylboronic acids using N-iodomorpholinium iodide (NIMI) as a novel iodinating agent: mild and regioselective synthesis of aryliodides
Tale,Toradmal,Gopula
, p. 84910 - 84919 (2015/10/28)
A mild and efficient protocol for the ipso-iodination of aryl boronic acids using N-iodomorpholinium iodide (NIMI) generated in situ from morpholine and molecular iodine as a novel iodinating agent has been developed. The addition of a catalytic amount of copper iodide found to promote rate enhancement of the iodination reaction and dramatic increase in the yield depending upon the nature of the boronic acid was observed. The mechanistic study revealed that depending upon the nature of the substrate, either the classical ipso substitution or copper catalysed iododeborylation pathway overall dominates the present iodination reaction. The features such as mild reaction conditions, operational simplicity, high to excellent yields, excellent functional group compatibility and low catalyst loading make this method potentially useful in organic synthesis.
