22098-62-0Relevant articles and documents
1,2-functionalized imidazoles as palladium ligands: An efficient and robust catalytic system for the fluorine-free Hiyama reaction
Martinez, Regina,Pastor, Isidro M.,Yus, Miguel
supporting information, p. 872 - 877 (2014/03/21)
A variety of hydroxy- and amino-functionalized imidazoles were prepared from 1-methyl- and 1-(diethoxymethyl)imidazole by means of isoprene-mediated lithiation followed by reaction with an electrophile. These compounds in combination with palladium acetate were screened as catalyst systems for the Hiyama reaction under fluorine-free conditions using microwave irradiation. The systematic study of the catalytic system showed 1-methyl-2-aminoalkylimidazole derivative L1 to be the best ligand, which was employed un-der solvent-free conditions with a 1:2 Pd/ligand ratio and TBAB (20 mol-%) as additive. The study has revealed an interaction between the Pd/ligand ratio and the amount of TBAB. The established catalytic system presented a certain degree of robustness, and it has been successfully employed in the coupling of a range of aryl bromides and chlorides with different aryl siloxanes. Furthermore, both reagents were employed in an equimolecular amount, without an excess of organosilane.
Isoprene-catalysed lithiation: deprotection and functionalisation of imidazole derivatives
Torregrosa, Rosario,Pastor, Isidro M.,Yus, Miguel
, p. 947 - 952 (2007/10/03)
The isoprene-catalysed lithiation of different 1-substituted imidazoles (1) (such as trityl, allyl, benzyl, vinyl, N,N-dimethylsulfamoyl, para-toluenesulfonyl, tert-butoxycarbonyl, acetyl, trimethylsilyl, tert-butyldimethylsilyl derivatives) leads to the