Coordination properties of novel hemilabile acetamide-derived P,O phosphine ligands. Crystal structures of Ph2PNHC(O)Me and [PdMe{PPh2NHC(O)Me}{PPh2NHC(O)Me}][O3SCF3] †

Abstract

Cationic methyl Pd() complexes are described in which the new heterofunctional phosphine ligands Ph 2 PNHC(O)Me 1 or Ph 2 PN(Me)C(O)Me 3 behave as rigid and/or hemilabile P,O chelates. The chelating ability of 3 is higher than that of 1 and both are compared to that of other P,O ligands, such as the keto-and amido-phosphines Ph 2 PCH 2 C(O)Ph and Ph 2 PCH 2 C(O)NPh 2 , respectively. The crystal structure of 1 reveals the presence in the solid-state of an intermolecular hydrogen-bonded network N-H ؒ ؒ ؒ O and that of12b establishes the presence of both a chelating and a monodentate ligand 1 in the same complex. Carbonylation of the cationic methyl complexes 8a, 17, 18a and 20a afforded the corresponding acetyl complexes in which this ligand occupies a position cis to phosphorus, irrespective of that of the alkyl ligand in the precursor complex.

An Oriented 1D Coordination/Organometallic Dimetallic Molecular Wire with AgPd Metal–Metal Bonds

“…[13] Accordingly, the NCH 2 protons only show a doublet in the 1 H NMR spectrum as a result of coupling to the P atom. The O1ÀC10 and N2ÀC10 bond lengths of 1.273(9) and 1.353 (9) , respectively, are consistent with CPO and NPC bond orders intermediate between single and double bonds. [7,9,14] A solution of 3 in THF was then treated with pure, acidfree AgSO 3 CF 3 in a 1:1 stoichiometry, and slow crystallization afforded high yields of a beige product 5·SO 3 CF 3 [Eq.…”

“…The O1ÀC10 and N2ÀC10 bond lengths of 1.273(9) and 1.353 (9) , respectively, are consistent with CPO and NPC bond orders intermediate between single and double bonds. [7,9,14] A solution of 3 in THF was then treated with pure, acidfree AgSO 3 CF 3 in a 1:1 stoichiometry, and slow crystallization afforded high yields of a beige product 5·SO 3 CF 3 [Eq. (2)], which was shown by X-ray diffraction studies to be an unprecedented Ag-Pd coordination polymer (Figure 2 and see the Supporting Information).…”

“…Furthermore, the simple exchange of a CH group by an N atom can bring about interesting electronic and geometric differences in molecular complexes, as shown with the phosphanes Ph 2 PNHC(O)R and Ph 2 PCH 2 C(O)R, [9] or induce unexpectedly large effects in supramolecular chemistry. [10] We have now found that metal coordination at the nitrogen atom of the P,O chelate in a complex of type 2: 1) readily leads to (m-P,N)-bridged heterodimetallic complexes, 2) occurs with retention of the planar coordination geometry at the nitrogen atom, and rather unexpectedly 3) opens an unprecedented route to ordered structures containing alternating metals in heterodimetallic units to form oriented, 1D coordination/organometallic polymers.…”

A hydroxyaminophosphane derived from 2-imidazolidone and its unusual structure in solution

“…To avoid difficulties with additional NH-functionalities, the N,N'-dialkyl compounds are usually utilised. In addition, the closely related N-phosphinated carboxylic acid amides were also investigated [1,6,7], although they met with significantly less interest due to their increased sensitivity towards hydrolysis.…”

<b>Synthesis and characterisation of some metal complexes of hybrid phosphorus-nitrogenligands: the crystal structure of 1-(diphenylphosphino)-2-(2-pyridyl)ethane cobalt(II) chloride</b>

“…Some efforts in coordination chemistry research have recently been directed towards the study of metal complexes of the hybrid hemilabile P-N- [5][6][7][8][9][10][11][12], P-O- [13,14] or P-S- [15][16][17] type ligands. This is due to their structural features, reactivity and catalytic properties resulting from the combination of a soft phosphine moiety with a hard oxygen-or nitrogen-donor functionality.…”