Insertion of internal acetylenes into orthopalladated α-methylbenzylamine. Crystal structure of [Pd{C(Ph)C(Ph)C(Ph)C(Ph)C6H4CH(Me)NH2}Br]
- 1 January 1995
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in J. Chem. Soc., Dalton Trans.
- No. 15,p. 2529-2533
- https://doi.org/10.1039/dt9950002529
Abstract
The complex [Pd{C6H4CH(Me)NH2}(Me2CO)2]ClO4 reacted with diphenylacetylene to give [Pd2(η5-C5Ph5)2(µ-η2-PhCCPh)]. A pathway for this reaction is suggested. Species related with the postulated intermediates can be isolated starting from [{Pd[C6H4CH(Me)NH2](µ-Br)}2] which reacts with disubstituted alkynes (RCCR, R = CO2Me or Ph) to afford [Pd{C(R)C(R)C(R)C(R)C6H4CH(Me)NH2}Br](R = CO2Me 1a or Ph 1b) through a double insertion of the alkyne into the Pd–C bond. Complex 1a reacted with 1 equivalent of MeO2CCCCO2Me to give the tri-insertion reaction product 2. These are the first products of alkyne insertion into a cyclopalladated primary amine. Neutral ligands, such as pyridine (py) or CO, can break the Pd–π-olefinic bond in 1a to give the corresponding adducts [Pd{C(R)C(R)C(R)C(R)C6H4CH(Me)NH2}Br(L)](R = CO2Me; L = py 3 or CO 4). Complexes 1a and 1b reacted with AgClO4(1 : 1) in acetone to afford AgBr and [Pd{C(R)C(R)C(R)C(R)C6H4CH(Me)NH2}(solv)]ClO4(R = CO2Me, solv = H2O 5a; R = Ph, solv = Me2CO 5b). The reaction of complex 1a with AgClO4(1 : 1) and excess of pyridine gave the cationic complex [Pd{C(R)C(R)C(R)C(R)C6H4CH(Me)NH2}(py)2]ClO46(R = CO2Me). The crystal structure of complex 1b has been determined by X-ray diffraction. The palladium atom is bonded to Br, N, C(1) and to the midpoint of the C(3)–C(4) double bond in a distorted square-planar geometry.Keywords
This publication has 29 references indexed in Scilit:
- Synthesis and identification by high-pressure NMR spectroscopy of the cationic square-planar cis-methyl(carbonyl)palladium diphosphine compound [Pd(CH3)(CO)[(S,S)-BDPP]]BF4, an intermediate in CO insertion into the Pd-Me bondJournal of the American Chemical Society, 1993
- Insertion of alkynes into the palladium-carbon bond of palladacycles. Mechanistic information from high-pressure kinetic and x-ray structural dataOrganometallics, 1993
- Intramolecular carbo- and heterocyclization induced by systematic demetalation of (.eta.3-butadienyl)palladium complexesOrganometallics, 1993
- New neutral and ionic methyl and chloro palladium and platinum complexes containing hemilabile phosphorus-nitrogen ligands. Study of the insertion of carbon monoxide into the metal-methyl bondOrganometallics, 1992
- Reactivity of cyclopalladated compounds. 28. Alkyne reactions with the cyclopalladated 8-methylquinoline ligand. Synthesis of novel heterocyclic compounds with a bridgehead nitrogenThe Journal of Organic Chemistry, 1992
- Reactivity of cyclopalladated compounds. 27. Metal-induced 1,5- and 1,4-hydrogen shifts in polysubstituted butadienyl units .eta.3-bonded to palladiumOrganometallics, 1992
- Anionic (nitrophenyl)palladium(II) carbonyls. Crystal structure of cis-[PPh3(CH2Ph)][Pd(C6H3Me-2,NO2-6)Cl2(CO)]Organometallics, 1991
- Reactivity of cyclopalladated compounds. 23. Formal carbon-carbon triple-bond splitting in an organopalladium compoundOrganometallics, 1990
- The synthesis of N-heterocycles using ortho-metallated primary benzylamine complexes of palladium(II) and platinum(II)Journal of the Chemical Society, Chemical Communications, 1984
- Carbonylation reactions of ortho-palladation products of .alpha.-arylnitrogen derivativesThe Journal of Organic Chemistry, 1975