Syntheses of N‐(Diphenylphosphanyl)‐2‐pyridylmethylamine and Its Use as a Ligand in Magnesium and Zinc Complexes

Abstract

The metathesis reaction of lithium 2-pyridylmethylamide with chloroalkanes and phosphanes yields N-and C-substitution products depending on the electrophile. Thus, C-alkylated 1-amino-1-(2-pyridyl)-2,2-dimethylpropane (1) and 1-amino-1-(2-pyridyl)-2phenylethane (2) and N-substituted N-benzyl-(2-pyridylmethyl)amine (3) and N-(diphenylphosphanyl)-2-pyridylmethylamine (4) are obtained. In [1·LiCl] 2 , molecule 1 binds to the lithium atom in a bidentate fashion. C-and N-substituted 2-pyridylmethylamines are compared with quantum chemical methods. Lithiation of 4 and subsequent reaction with cloro-diphenylphosphane yields N,N-bis(diphenylphosphanyl)-2-pyridylmethylamine (5) with a planar amine nitrogen atom. Metallation of 4 with dibutylmagnesium 893 leads to the formation of colorless (tetrahydrofuran)magnesium bis[N-(diphenylphosphanyl)-2-pyridylmethylamide] (6) with a penta-coordinate alkaline earth metal atom in a trigonal bipyramidal environment. In contrast to this observation, the reaction of 4 with dimethylzinc yields colorless methylzinc bis[N-(diphenylphosphanyl)-2-pyridylmethylamide] (7). Zincation of 1 gives dimeric methylzinc 1-(2-pyridyl)-2,2-dimethyl-1-propylamide (8). In these zinc complexes the metal and amide nitrogen atoms are in distorted tetrahedral environments.

Reaction of [(tmeda)NiMe2] with 2-pyridylmethylamine and (2-pyridylmethyl)(diphenylphosphanyl)amine

“…The nickel atoms of 2 are in slightly distorted tetrahedral environments with an average Ni-P bond length of 216.9 pm. The P-N distances show an average value of 169.5 pm which is comparable to the P-N bonds of [MeZn-N(CH 2 Py)PPh 2 ] 2 but smaller than observed for Py-CH 2 -N(PPh 2 ) 2 [12].…”

“…A reaction in THF gives lower yields of approximately 20% due to accompanying decomposition reactions. The bulkier N-diphenylphosphanyl-2-aminomethylpyridine [12] reacts with [(tmeda)NiMe 2 ] yielding tetrakis(N-diphenylphosphanyl-2-aminomethylpyridine)nickel(0) 2 [13]. Rather poor yields of 2 were obtained due to the fact that also decomposition takes place during this reaction yielding ethane and nickel(0).…”

Structure of salts of lithium chloride and lithium hexafluorophosphate as solvates with pyridine and vinylpyridine and structural comparisons: (C5H5N)LiPF6, [p-(CH2=CH)C5H4N]LiPF6, [(C5H5N)LiCl] n , and [p-(CH2=CH)C5H4N]2Li(μ-Cl)2Li[p-(CH2=CH)C5H4Jalil1, Clymer2, Hamilton3 et al. 2017Acta Crystallogr C2000View full textAdd to dashboardCite

“…In the presence of pyridine, LiCN also forms a polymeric one-dimensional ionic network with cyanide ligands bridging between neighboring Li(Py) 2 + cations (Purdy et al, 1997). Particularly relevant to this report are complexes of lithium halide salts with pyridyltype ligands, which have been shown to form dimers (Westerhausen et al, 2004;Olbert et al, 2007;Raston et al, 1988Raston et al, , 1990 or monomers (Raston et al, 1988a(Raston et al, , 1990. In one case, in a diaquadipyridyllithium complex, the bromide anion was excluded from the Li coordination sphere (Raston et al, 1988b).…”

Bis(diphenylphosphino)amines-containing ruthenium cymene complexes as potential anti-Mycobacterium tuberculosis agents

“…Worth noting is the compression in the PeNeP versus PeCeP bond angles of the free ligand compared to the coordinated one. For example, the PeNeP bond angle for free PeN Mepy eP is 121.8(1)° [16] and coordinated is 100.32(14)°( complex [1a]%PF6), while for dppm, the bond angle for the free ligand is 107.63(10)°and upon coordination the angle in compressed to 95.3(3)° [50]. The strong compression observed for the PeNeP ligands may be a consequence of the bulky R substituents on nitrogen atoms.…”

“…For example, the PPh 2 (CH 2 )PPh 2 (bis[diphenylphosphino]methanedppm) and PPh 2 NHPPh 2 (bis[diphenylphosphino]aminedppa) are isoelectronic, but their 31 P NMR chemical shift are −23.6 [15] and 42.1 ppm [14], respectively. It is clear they have different electronic properties due to the lower electronegativity of the carbon compared to the nitrogen and the presence of a lone electron pair centered on nitrogen, which is delocalized over the PeNeP bonds through pz(N)-σ*(PeC) overlap [16] as a result, the nitrogen atom is sp 2 hybridized.…”