Annulation of five-membered cyclic enols with 3-aryl-2H-azirines: Catalytic versus non-catalytic cycloaddition

Add time:07/25/2019    Source:sciencedirect.com

A copper(I)-NHC-catalyzed annulation of 5-membered cyclic enols of furan, thiophene and indene family with 3-aryl-2H-azirines has been developed to provide a rapid access to furo[3,4-b]pyrrole, thieno[3,4-b]pyrrole, indeno[1,2-b]pyrrole derivatives. The reaction proceeds via a copper-initiated NC2 azirine bond cleavage with the retention of the CN double bond in the annulation product. The reaction of tetronic acids with 3-aryl-2H-azirines can also proceed under catalyst-free conditions, through a double addition of the enol to the azirine, but this route provides poor yields of the annulation products. This is the first example of the NC2 bond cleavage in 2-unsubstituted 2H-azirines in the absence of a transition metal catalyst.

We also recommend Trading Suppliers and Manufacturers of TETRAHYDRO-5-OXO-2-PHENYLFURAN-3-CARBOXYLIC ACID (cas 13389-88-3). Pls Click Website Link as below: cas 13389-88-3 suppliers

Prev:Discovery of N-{5-[3-(3-hydroxypiperidin-1-yl)-1,2,4-oxadiazol-5-yl]-4-methyl-1,3-thiazol-2-yl}acetamide (TASP0415914) as an orally potent phosphoinositide 3-kinase γ inhibitor for the treatment of inflammatory diseases
Next:History of Yellow River and Yangtze River delivering sediment to the Yellow Sea since 3.5 Ma: Tectonic or climate forcing?)