Consecutive One-Pot Sonogashira-Glaser Coupling Sequence - Direct Preparation of Symmetrical Diynes by Sequential Pd/Cu Catalysis
作者:Eugen Merkul、Dominik Urselmann、Thomas J. J. Müller
DOI:10.1002/ejoc.201001472
日期:2011.1
Sonogashira coupling and the catalytic Glaser coupling are both catalyzed by the Pd-Cu complex couple and can be concatenated to a consecutivesequentiallyPd/Cu-catalyzed process in a one-pot fashion, and air oxygen serves as the only oxidant in the second step. In a pseudo-four-component synthesis, a broad variety of symmetrically substituted 1,4-bis(hetero)aryl-1,3-butadiynes are obtained in good
A convenient synthesis of 1,4-disubstituted imidazoles
作者:Yong He、Yingzhong Chen、Hongwang Du、Lesley A Schmid、Carl J Lovely
DOI:10.1016/j.tetlet.2004.05.011
日期:2004.7
An efficient method for the regioselective protection of 4-alkyl-, 4-iodo, 4-vinylimidazoles has been developed via an alkylation–isomerization sequence with various imidazole-protecting groups. The initially formed mixture of 4/5-alkyl-, 4/5-iodo, and 4/5-vinylimidazoles are isomerized to the corresponding 4-isomers on treatment of a DMF solution with a small amount of RX and heating at 75 °C.