Generation of 19-Electron Adducts in Aqueous Solution Using the Water-Soluble (HOCH₂)₂PCH₂CH₂P(CH₂OH)₂Ligand

Abstract

The utility of the water-soluble (HOCH2)2PCH2CH2P(CH2OH)2 ligand (dhmpe) in generating 19-electron complexes in aqueous solution was tested. In buffered aqueous solutions at pH 2, the ligand reacts with 17-electron radicals generated by photolysis of water-soluble [(CpCH2CH2NH3 +)2Mo2(CO)6][NO3 - ]2 to form 19-electron adducts. The formation of 19-electron adducts was established by disproportionation of [(CpCH2CH2NH3 +)2Mo2(CO)6][NO3 - ]2 and by the reduction of methyl viologen, both standard indicators of 19-electron adduct formation. The crystal structures of the (HOCH2)2PCH2CH2P(CH2OH)2 ligand and of one of its complexes, [Ni(dhmpe)2]Cl2, were determined.

New Oligophosphines and (Hydroxymethyl)phosphonium Chlorides

“…16 Selected structural parameters for 14 are given in Table 2. The distance between the C atoms of the ethane bridge, 1.534(4) Å, and the P-C distances are in the range seen for the reported structures of (HOCH 2 ) 2 PCH 2 CH 2 P(CH 2 -OH) 2 , 23 [HO(CH 2 ) 3 ] 2 PCH 2 CH 2 P[(CH 2 ) 3 OH] 2 , 10c and R 2 PCH 2 -CH 2 PR 2 (R ) Me, Et, or i Pr). 24 The P atoms exhibit tetrahedral coordination with C-P-C angles in the range of 108.61-111.45°.…”

Cyclohexylbis(hydroxymethyl)phosphane: A Hydrophilic Phosphane Capable of Forming Novel Hydrogen‐Bonding Networks

“…The compound crystallizes monoclinic with two independent molecules 1A and 1B in the unit cell (Figure 2). Their atomic distances and angles are practically identical and resemble the respective values observed for the related bis(hydroxymethyl) phosphanes (Fc-P(CH 2 OH) 2 , [15] FcCH 2 P-(CH 2 OH) 2 [2] or (HOCH 2 ) 2 P-CH 2 CH 2 -P(CH 2 OH) 2 [13] . (15) 1.778(9) P(2)-C(12) 1.790(9) P(1)-C (13) 1.778 ( In contrast to the limited geometrical analysis of 1, the crystal structure determinations of the phosphane derivatives CyP(O)(CH 2 OH) 2 3 and CyP(S)(CH 2 OH) 2 4 afforded better data sets (see Table 5) suitable for a topological analysis of the hydrogen-bonding networks.…”

“…The 1 H NMR spectra of both compounds show unresolved overlapping multiplets for the methylene protons of the PCH 2 OH groups, which indicate the expected chemical inequivalence (AB part of an ABX spin system; A, B = 1 H; X = 31 P) of the latter. The 13 C nucleus of the PCH 2 OH groups exhibits a doublet in the 13 C{ 1 H} NMR spectra of 3 and 4, respectively, with characteristically large 1 J(P,C) coupling constants (3: 75.6 Hz; 4: 66.7 Hz) for phosphane chalcogenides.…”

“…However, there are only a few examples known, demonstrating that (hydroxymethyl) phosphanes and their chalcogenides [1] are able to form intermolecular hydrogen bonds. To our surprise, structural investigations are rather rare and only available for (HOCH 2 ) 2 P-CH 2 CH 2 -P(CH 2 OH) 2 , [13] ferrocenyl (Fc)-substituted (hydroxymethyl)phosphanes, [2,14,15] and their derivatives FcP(X)(CH 2 OH) 2 (X = O, S), [14,15] FcCH 2 P(S)(CH 2 OH) 2 [2] and FcCH(CH 3 )P(S)(CH 2 OH) 2 , [16] respectively. We report here the synthesis and characterization of a variety of new cyclohexyl-derived bis(hydroxymethyl) phosphane compounds.…”

Reactions of coordinated hydroxymethylphosphines with NH-functional amines: the phosphorus lone pair is crucial for the phosphorus Mannich reaction

“…14 Of the watersoluble phosphines, hydroxymethylphosphines (R n P(CH 2 OH) 3-n ) are especially attractive because of their straightforward preparation from PH-functional phosphines (or PH 3 ) and formaldehyde (eqn (1)). [15][16][17][18][19][20][21] The hydroxymethylphosphine ligands are easily functionalized by using the phosphorus Mannich reaction with NHfunctional amines (eqn (2)). [22][23][24][25][26][27][28][29][30][31] Phosphine ligands with ancillary amino groups are useful because they can provide basicity in the secondary coordination sphere of metal complexes and because complexes with such ligands can activate small molecule substrates as both Lewis acids and Lewis bases.…”