90150-43-9Relevant academic research and scientific papers
Phenol Formation from the Reaction of Amino-Stabilized Alkenyl Fischer Carbene Complexes
Wulff, William D.,Gilbert, Adam M.,Hsung, Richard P.,Rahm, Annette
, p. 4566 - 4575 (2007/10/02)
The first examples of phenol formation from the reactions of amino-stabilized α,β-unsaturated Fischer carbene complexes with alkynes are reported.A series of four dimethylamino complexes were examined with both internal and external alkynes.Their reactions with internal alkynes typically produced low yields of complex mixtures of products and were not synthetically useful.In contrast, their reactions with terminal alkynes were remarkably different giving good yields of 4-(dimethylamino)phenols, and in the presence of a trapping agent, good yields of the arene chromium tricarbonyl complexes of the protected 4-(dimethylamino)phenols.The selectivity for phenol formation was found to be greatest for reactions performed in noncoordinating solvents and at higher concentrations.In contrast, and as expected, the reaction of the aryl complex 45 with 1-pentyne did not produce any six-membered ring product in DMF, THF, or benzene.An interesting solvent dependence was observed for this reaction where lactam 49 was the exclusive product in benzene and the indanone 46 was the exclusive product in DMF.
Benzannulation of α,β-Unsaturated Fischer Carbene Complexes with Acetylenes
Wulff, William D.,Chan, Kin-Shing,Tang, Peng-Cho
, p. 2293 - 2295 (2007/10/02)
The reaction of acetylenes with α,β-unsaturated chromium carbene complexes allows for the controlled construction of an aromatic nucleus under neutral conditions at near ambient temperatures.The synthetic scope of the reaction is examined for eight different carbene complexes with a variety of acetylenes to give three different types of benzannulated products depending on the type of oxidative workup employed.
