Tributyltin hydride-tetrakis palladium

The reaction of 5-chloro-l,4-benzoxazepine (4), whose preparation is described below, with tributyltin hydride catalyzed by tetrakis(triphenylphosphane)palladium(0) gives 1,4-benzox-azepine (5).32... 

Palladium(II) trifluoroacetate, 236 Sodium borohydride-Tetrakis(tri-phenylphosphine)palladium(O), 168 Tetrakis(triphenylphosphine)palla-dium(0), 34, 103, 126, 142, 169, 202, 211, 220, 271, 289 Tetrakis(triphenylphosphine)palla-dium(0)-l, 2-Bis(diphenylphos-phine)ethane, 290 Tetrakis(triphenylphosphine)palla-dium(0)-Zinc, 346 Tributyltin hydride-Dichlorobis-(triphenylphosphine)palladium(II), 319... 

Enol ethers of alkyl cyclopropyl ketones are alkylated or carboxylated under the correct conditions. Methyl ann, c ,cw-2,9,9-trimethyl-5-trifluoromethylsulfonyloxytricyclo[5.3.0.0 " ]dec-5-ene-4-carboxylate on treatment with palladium(II) acetate in methanol containing triethylamine under a carbon monoxide atmosphere resulted in diester formation giving dimethyl fln ,c .5,cw-2,9,9-trimethyltricyclo[5.3.0.0 ]dec-5-ene-4,5-dicarboxylate in excellent yield (93%). The same substrate was converted to methyl anr/,cw,d. -5-formyl-2,9,9-trimethyltricyclo[5.3.0.0 ]dec-5-ene-4-carboxylate in 88% yield on carbonylation in the presence of tetrakis(triphenylphosphane)palladium, tributyltin hydride, and lithium chloride. ... 

The fully aromatic species are usually quite resistant to hydride reduction. Attempted reduction of l,2-dimethyl-5-nitroimidazole with tributyltin hydride failed to yield 1,2-dimethylimidazole <90JCS(Pl)9l9>, but the apparent reduction of 5-iodo-l-methylimidazole to l-methylimidazole by phenylsulfonylacetonitrile and sodium hydride with tetrakis(triphenylphosphine)palladium(0) as catalyst may be an example <92S552>. Lithium aluminum hydride (but not diborane) is able to convert 2-(but not 4-)fluoroimidazoles into the hydrogen species <84JOCi95i>. 

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