Coupling reactions palladium® acetate - phase-transfer

Joint catalysis by tin(IV) chloride and zinc chloride induces coupling of the acetal 114 with the alkyne 115 to give the propargyl ether 116. Allyl halides condense with terminal alkynes in DMF in the presence of copper(I) iodide, potassium carbonate and tetrabutylammonium chloride under phase-transfer conditions to afford eneynes, e.g. equation 19. Palladium-catalysed coupling reactions of 1-bromoallenes with terminal acetylenes have been reported for the first time thus acetylene and the allenes 117 (R R = Me or Et) in triethylamine in the presence of tetrakis(triphenylphosphine)palladium and... 

Leadbeater et al. recently showed that the PTC procedure with MW irradiation can be used to prepare of biaryls using water, palladium acetate, and TBAB as solvent, catalyst, and phase-transfer agent, respectively [117]. The desired coupling products were obtained in good yield (60 to 90%). The reaction can, however, be performed equally well using MW and conventional heating methods. Although it... 

Palladium (II) acetate, tetrabutyl ammonium bromide (a phase-transfer catalyst) and potassium carbonate in a mixture of acetonitrile and water, which were originally published by Jeffery in 1996 for Heck reactions, have also been applied to C-H activation of thiophenes. Lemaire and coworkers have coupled a number of 2- and 3-substituted thiophenes (-CHO, -NO2, -CN) with iodobenzenes, albeit in low yields (Scheme 19.2). 

A double coupling of 2-amidoacrylates with 3,3 -diiodobiphenyl constitutes a key step in a short preparation of a biphenomycin B analog. Palladium acetate-catalyzed double coupling reactions of 1,8-diiodonaphthalene with substituted alkenes and alkynes under phase-transfer conditions are useful also for the synthesis of various acenaphthene and acenaphthylene derivatives. ... 

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