Tris(N-{bis[methyl(phenyl)amino]phosphoryl}benzenesulfonamidato-κ2 O,O′)(1,10-phenanthroline-κ2 N,N′)lanthanum(III)

A lanthanum(III) complex with formula LaL 3Phen (where L − is the sulfonylamidophosphate (SAPh)-type ligand N-{bis[methyl(phenyl)amino]phosphoryl}benzenesulfonamidate, C6H5SO2NHPO[N(CH3)C6H5]2 has been synthesized and its crystal structure determined.


Chemical context
-Diketone derivatives have been the topic of investigations in many different branches of the chemical science, such as organic, coordination, bio-and theoretical chemistry. Of special interest have been carbacylamidophosphates (CAPh), containing the functional fragment C(O)NHP(O), because of their properties as extractants (Morgalyuk et al., 2005;Safiulina et al., 2015), urease inhibitors (Jaroslav & Swerdloff, 1985), enzyme inhibitors (Grimes et al., 2008;Adams et al., 2002), their antibacterial properties (Oroujzadeh et al., 2017) and anticancer activity (Kovalchyk et al., 1991;Amirkhanov et al., 1995). The presence of the phosphoryl group gives them a high affinity towards highly charged metal ions, and these types of compounds are used in the coordination chemistry of lanthanides and actinides (Litsis et al., 2010(Litsis et al., , 2017Kariaka et al., 2013). Many efforts have been devoted to the synthesis of another type of structural analogs of -diketones -sulfonylamidophosphates (SAPh) with the structural fragment S(O) 2 NHP(O). These types of compounds were first synthesized by Kirsanov (Kirsanov & Shevchenko, 1954) and some have since been used as bactericidal agents in medicine and toxicology (Xu & Angell, 2000), while others have found use as pesticides (Kishino & Saito, 1979). In addition, these compounds are potentially bidentate O,O-donor chelating ligands for metal ions, similar to other deprotonated phosphorylic ligand derivatives (Znovjyak et al., 2015;Amirkhanov et al., 2014;Litsis et al., 2016;Shatrava et al., 2016a). For details of the coordination chemistry of phosphorylic ligands in molecular form, see Gholivand et al. (2012Gholivand et al. ( , 2014, Yizhak et al. (2013) and Shatrava et al. (2016b).
Recently, we reported the preparation and study of the coordination properties of several representatives of sulfonylamidophosphates: methyl(phenylsulfonyl)amidophosphate [PhSO 2 NHP(O)(OMe) 2 ] (Moroz et al., 2007) and particularly the photophysical properties of a series of NIRemitting lanthanide complexes (Kulesza et al., 2010). It was shown that the solid-state decay time for the ytterbium complex is one of the longest of all known Yb III complexes with organic ligands. It is expected that depending on the nature of substituents attached to the phosphorus and sulfur atoms, these organic compounds and their complexes might demonstrate unique specific physicochemical properties. Optical studies of the etheric type SAPh ligands dimethyl(4methylphenylsulfonyl)amidophosphate [(Me)PhSO 2 NHP(O)-(OMe) 2 ] and dimethyl 2-naphthylsulfonylamidophosphate [(C 10 H 7 )SO 2 NHP(O)(OMe) 2 ] indicate that the ligand first excited singlet state plays a dominant role in intramolecular energy transfer processes in these Ln complexes (Kasprzycka et al., 2016).
Knowledge of the crystal structure is an essential part of understanding the luminescent properties of these types of lanthanide complexes. In this paper we would therefore like to report the molecular and crystal structure of a lanthanum coordination compound based on the amidic type SAPh ligand N-(methyl(phenylamino)phosphoryl)benzenesulfonamide (HL) [PhSO 2 NHP(O)(N(Me)Ph) 2 ] with the general formula La(L) 3 Phen.

Structural commentary
The title compound La(L) 3 Phen crystallizes with one molecule in the asymmetric unit (Fig. 1). The coordination environment of the La atom consists of two nitrogen atoms of 1,10-phenanthroline and six oxygen atoms from the three acido-SAPh ligands.
The SAPh ligands coordinate to the lanthanide atom in the acido form in a bidentate manner with formation of sixmembered metallocycles with partial delocalization ofelectron density.  (Zefirov et al., 1990)). The deviations of the N1 and O1 atoms from the mean plane through the remaining atoms of A (r.m.s.deviation = 0.06 Å ) are 0.78 and 0.41 Å , respectively. The deviations of the La1 and O3 atoms from the mean plane through the remaining atoms of B (r.m.s.deviation = 0.06 Å ) are 0.9 and 0.88 Å , respectively. The La1-O2-P2-N2-S2-O7 (C) ring adopts a flattened half-chair conformation (puckering parameters are: S = 0.71, = 16.51 , = 20.43 ). The deviation of the La1 atom from the mean plane carried through the remaining atoms of ring C (r.m.s.deviation 0.02 Å ) is 0.36 Å .

Supramolecular features
In the crystal phase, the La(L) 3 Phen molecules are linked by weak C-HÁ Á ÁO hydrogen bonds (Table 1), forming double layers parallel to the (010) plane (Fig. 3). There are solventaccessible voids with a total volume of 380 Å 3 . The content of the voids is not resolved in difference-density maps, with the largest residual electron density peak being only 0.66 electrons per Å 3 . A SQUEEZE (Spek, 2015)  The crystal packing of LaL 3 Phen. The view is along the crystallographic a axis.

Figure 2
The coordination polyhedron around the central La III atom in LaL 3 Phen with b parameters indicated. overall electron count matching approximately three molecules of the solvent (2-propanol) per unit cell, but did not improve R values or other quality indicators (see Refinement section).

Database survey
A search of the Cambridge Structural Database (CSD, Version 5.38, update February 2017;Groom et al., 2016) for SAPh ligand analogues with derivatives of the N-(bis(diamino)phosphoryl)sulfonamide fragments yielded five hits, with only one metal complex structure with a neodymium metal atom among them (Shatrava et al., 2010). In this molecule, the neodymium atom is also octacoordinated, with a highly symmetrical NdO 8 polyhedron and no coordinating N atoms.
A search for phenanthrolinate REE complexes with other SAPh-type ligands returned one entry for tris(dimethyl

Synthesis and crystallization
1 H and 31 P NMR spectra in DMSO-d 6 solutions were recorded on a Varian 400 NMR spectrometer at room temperature. 1 H chemical shifts were determined relative to the internal standard TMS whereas 31 P chemical shifts were determined relative to 85% H 3 PO 4 as an external standard. Infrared (FTIR) spectra were recorded on a Perkin-Elmer Spectrum BX spectrometer using KBr pellets. The resolution of the FTIR spectra is 1 cm À1 .
During the refinement, several small isolated electrondensity peaks were located in solvent-accessible voids that were believed to be solvent molecules. The largest residual electron peak accounted to 0.66 e Å 3 . Satisfactory results (R 1 = 5.01%) were obtained modeling disordered C and O atoms, but very large displacement parameters for them were observed. The SQUEEZE procedure (Spek, 2015) implemented in PLATON indicated two solvent cavities each of volume 380 A 3 , each containing approximately 52 electrons, which corresponds to approximately three molecules of the solvent (2-propanol) per cell. However, the difference in R 1 values for the structures with and without the SQUEEZE procedure implemented was rather small (0.5%). In the final refinement, the isolated peaks in the solvent-accessible voids were ignored.   (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Tris(N-{bis[methyl(phenyl)amino]phosphoryl}benzenesulfonamidato-κ 2 O,O′)(1,10-phenanthrolineκ 2 N,N′)lanthanum(III)
Crystal data [La(C 20  Special details Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.