Intramolecular palladium-catalyzed aryl amination and aryl amidation

Synthesis and characterization in solution and in the solid State of the palladium aryl bromide complexes [Pd(Ar)Br{(S)-BINAP}]: formation of cyclopalladated complexes and direct observation of a C-N reductive elimination to form heterocycles

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As reações de uma mistura [Pd 2 (dba) 3 ]/P(o-tolyl) 3 (1/4) com brometos de arila orto substituídos conduziram aos dímeros [Pd(Ar)(µ-Br){P(o-tolyl) 3 )}] 2 que, após adição de 2 equiv. de (S)-BINAP formaram os complexos

){(S)-BINAP}] em bons rendimentos (57-89%

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Synthesis of 1,3-Oxazepine Derivatives Derived from 2-(1H-Benzo[d][1,2,3]Triazol-1-yl) Acetohydrazide by Using Microwave Irradiation

“…The 1 HNMR spectrum of compund (c 15 Figure 2) displayed a single peak appeared at 11.8 ppm which was assigned to chemical shift of NH and multiplet peak at 7.3 -7.8 ppm which were assigned to chemical shifts of aromatic protons at carbons (4,5,6,7,8,16,17,18,19). The peak at 5.5 ppm was attributed to the chemical shift of carbon (15) proton its between carbonyl amide and benzotriazol moiety.…”

“…But protons at carbons (11,12) in seven membered ring appeared at 6.1-6.3 ppm, the peak at 8.1 ppm was attributed to the chemical shift of carbon (9) proton due to between two highly electronegativity atoms (oxygen and nitrogen). The 1HNMR spectrum of the compound (C11 Figure 3) displayed a single peak appeared at 11.8 ppm which was assigned to chemical shift of NH and multiplet peak at 7.2 -7.9 ppm which were assigned to chemical shifts of aromatic protons at carbons (2,3,4,5,6,14,15,16,17). The peak at 5.5 ppm was attri- (13) proton its between carbonyl amide and benzotriazol moiety.…”

“…After completion of the reaction as indicated by TLC, the reaction mixture was cooled at room temperature and washed with mixed solvent (9:1) (ether: ethyl acetate). The products were recrystallized absolute ethanol to give yield (60% -90%) pure crystal of substituted hydrazones (3,4,5,6,8,9). The same procedure to prepare (7b,10b) was followed using (0.01 mol) furfuraldehyde and (0.01 mol) cinnimaldehyde.…”

Palladium-mediated synthesis of a new eight-membered heterocycle

“…Thus far a direct attack of the NH group to the arylpalladium bond, which would lead to the formation of a seven-membered ring, could not be obtained even working under conditions of strong basicity and in the presence of chelating ligands, according to procedures described in the literature. 13 The failure to close this ring, while the eight-membered one was readily formed, is likely due to steric hindrance in the congested transition state.…”