817181-75-2Relevant articles and documents
Thienyl MIDA boronate esters as highly effective monomers for Suzuki-Miyaura polymerization reactions
Carrillo, Josu Ayuso,Ingleson, Michael J.,Turner, Michael L.
, p. 979 - 986 (2015/09/08)
The synthesis of highly regioregular poly(3-hexylthiophene-2,5-diyl), rr-P3HT, by Suzuki-Miyaura polymerization is reported. The key N-methyliminodiacetic acid (MIDA) boronate ester thienyl monomer was synthesized using a one-pot multigram scale procedure, in high purity, and in good isolated yield (80%) by direct electrophilic borylation. Conditions for the hydrolysis of the MIDA protecting group and the polymerization reaction were investigated. The optimal procedure gave rr-P3HT with >98% HT couplings, excellent isolated yields (up to 94%), and polymer molecular weights up to Mn = 18.7 kDa and Mw = 42.7 kDa. The performance of the MIDA containing monomer was compared to that of the pinacol boronate ester under identical polymerization conditions, with the latter producing lower molecular weight polymers in reduced yield.
Modulating reactivity and diverting selectivity in palladium-catalyzed heteroaromatic direct arylation through the use of a chloride activating/blocking group
Liegault, Benoit,Petrov, Ivan,Gorelsky, Serge I.,Fagnou, Keith
supporting information; experimental part, p. 1047 - 1060 (2010/04/04)
(Chemical Equation Presented) Through the introduction of an aryl chloride substituent, the selectivity of palladium-catalyzed direct arylation may be diverted to provide alternative regioisomeric products in high yields. In cases where low reactivity is typically observed, the presence of the carbon-chlorine bond can serve to enhance reactivity and provide superior outcomes. From a strategic perspective, the C-Cl bond is easily introduced and can be employed in a variety of subsequent transformations to provide a wealth of highly functionalized heterocycles with minimal substrate preactivation. The impact of the C-Cl functional group on direct arylation reactivity has also been evaluated mechanistically, and the observed reactivity profiles correlate very well with that predicted by a concerted metalation-deprotonation pathway.
