Copper-catalyzed addition of water affording highly substituted furan and unusual formation of naphthofuran ring from 3-(1-alkenyl)-2-alkene-1-al

Aerobic Copper-Catalyzed Organic Reactions

“…The reaction is performed open to air using a copper(I) catalyst, generating the desired products in moderate yields (Scheme 258). 545 Here, the copper serves to activate the alkyne for nucleophilic attack by the aldehyde (Scheme 259). Displacement of the copper followed by hydration generates a secondary benzylic alcohol, which is then oxidized to the ketone.…”

Transition Metal-Mediated Synthesis of Monocyclic Aromatic Heterocycles

“…218 Zhang described a similar Au(III)-catalyzed transformation in the presence of hydrogen peroxide as a terminal oxidant. Thus, the oxidative cycloisomerization of 2-442 proceeded under very mild reaction conditions and afforded furans 2-443 in good yields (Scheme 124).…”

Palladium‐catalyzed three‐component cyclization of 2‐bromocyclohex‐1‐enecarboxylic acids with carbon monoxide and arylhydrazines leading to 2‐anilinohydroisoindoline‐1,3‐diones

“…[6][7][8][9][10][11][12][13][14][15][16][17][18][19] β-Bromo-α,β-unsaturated aldehydes and their derivatives are readily prepared from α-methylene group-containing ketones by bromination under Vilsmeier-Haack conditions [20,21] and subsequent transformation, and the products can serve as valuable building blocks for the construction of various cyclic compounds. [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] Among such carbonlative cyclization reactions, we recently have shown that β-bromo-α,β-unsaturated carboxylic acids can be carbonylatively cyclized with 2,2-dimethylhydrazine under carbon monoxide pressure in the presence of a palladium catalyst to give 1-(dimethylamino)-1H-pyrrole-2,5-diones. [39] The present work arose during the course of the application of this protocol to the reaction with arylhydrazines.…”