Crystal structure of 1,3-di-tert-butyl-2-chloro-1,3,2-di­aza­phospho­rinane − a saturated six-membered phospho­rus nitro­gen heterocycle with a partially flattened chair conformation and a long PIII—Cl bond

Mecke, E.; Frank, W.

doi:10.1107/S2056989019004195

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ISSN: 2056-9890

Volume 75| Part 5| May 2019| Pages 552-556

https://doi.org/10.1107/S2056989019004195

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Crystal structure of 1,3-di-tert-butyl-2-chloro-1,3,2-diazaphosphorinane − a saturated six-membered phosphorus nitrogen heterocycle with a partially flattened chair conformation and a long P^III—Cl bond

Erik Mecke ^a and Walter Frank ^a ^*

^aInstitut für Anorganische Chemie und Strukturchemie, Lehrstuhl II: Material- und Strukturforschung, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
^*Correspondence e-mail: wfrank@hhu.de

Edited by S. Parkin, University of Kentucky, USA (Received 7 March 2019; accepted 28 March 2019; online 2 April 2019)

Colourless blocks of 1,3-di-tert-butyl-2-chloro-1,3,2-diazaphosphorinane, C₁₁H₂₄ClN₂P (1), were obtained by sublimation in vacuo slightly above room temperature. The asymmetric unit of the monoclinic crystal structure of the six-membered N-heterocyclic compound is defined by one molecule in a general position. The six-membered ring of the molecule adopts a cyclohexane-like chair conformation; the chair at one side is to some extent flattened as a result of the approximately trigonal–planar coordination of both nitrogen atoms. In detail, this modified chair conformation is characterized by an angle of 53.07 (15)° between the plane defined by the three carbon atoms and the best plane of the two nitrogen atoms and the two carbon atoms bound to them, and an angle of 27.96 (7)° between the latter plane and the plane defined by the nitrogen and phosphorus atoms. The tert-butyl groups are oriented equatorially and the chloro substituent is oriented axially. The P—Cl bond length of 2.2869 (6) Å is substantially longer than the P—Cl single-bond length in PCl₃ [2.034 Å; Galy & Enjalbert (1982 ). J. Solid State Chem. 44, 1–23]. Inspection of the intermolecular distances gives no evidence for interactions stronger than van der Waals forces. The closest contact is between the Cl atom and a methylene group of a neighbouring molecule with a Cl⋯C distance of 3.7134 (18) Å, excluding a significant influence on the P—Cl bonding.

Keywords: crystal structure; phosphorus nitrogen compound; six-membered heterocycle; N-heterocyclic phosphorus compound; diazaphosphorinane; chlorophosphane; conformation.

CCDC reference: 1906304

1. Chemical context

Over the past two decades, P-chlorofunctionalized N-heterocyclic phosphanes (NHPCls) received considerable attention, mainly as precursors of N-heterocyclic phosphenium ions (NHPs) that are valence isoelectronic compounds of the well-known N-heterocyclic carbenes (NHCs) (Papke et al., 2017 ), but also as educts of tetrakis(amino)diphosphanes (e.g. Bezombes et al., 2004 ; Blum et al., 2016 ; Edge et al., 2009 ; Frank et al., 1996 ), some of which reversibly dissociate to stable phosphinyl radicals (`jack-in-the-box dipnictines'; Hinchley et al., 2001 ), and as starting materials in the synthesis of mixed-valent tetrakis(amino)tetraphosphetes (Breuers et al., 2015 ; Frank et al., 1996). Furthermore, NHPCls and NHPs have been used as ligands in transition metal complexes (Thomas et al., 2018 ), some of which have a potential application in catalysis (Gatien et al., 2018 ). In the context of NHP chemistry, the majority of compounds are five-membered cycles, and especially P-chlorofunctionalized 1,3,2-diazaphospholenes (Denk et al., 1996 ; Carmalt & Lomeli, 1997 ) have gained a widespread use as precursors for 1,3,2-diazaphospholenium cations (the most prominent class of NHPs) that are weak σ-donors and strong π-acceptors (Caputo et al., 2008 ; Tuononen et al., 2007 ). A limited number of structurally characterized examples is known for the class of P-chlorofunctionalized four-membered NHPCls Cl—P<(NR)₂>E and the related NHPs. The fourth ring member >E, joining the class-defining Cl—P<(NR)₂ fragment, is an >SiR₂ group in most cases (e.g. Breuers & Frank, 2016 ; Gün et al., 2017 ; Mo et al., 2018 ; Mo & Frank, 2019 ; Veith et al., 1988 ) but some compounds containing >C=N—R (Brazeau et al., 2012 ), >B—Ph (Konu et al., 2008 ) and >As—Cl (Hinz et al., 2015 ) have also been synthesized and structurally characterized. In contrast to the aforementioned compounds with four- and five-membered rings, six-membered NHPs and NHPCls are less present in recent publications, although 2-chloro-1,3,2-diazaphophorinanes H₂C<(CH₂NR)₂>P–Cl, for instance, have been known since the early 1970s (Maryanoff & Hutchins, 1972 ; Nifant'ev et al., 1977 ). Temperature-dependent dynamical NMR investigations showed that in solution these substances are not subject to a fast conformation change, like the ring-inversion process of cyclohexane, and that in the predominant conformation the chloro substituent is expected to be in the axial position and the residues on the nitrogen atoms are oriented `diequatorial'. This gives rise to a quite complex ¹H-NMR spectrum with an AA′KK′QTX pattern (X = P, AA′KK′ = C₄ and C₆ protons, Q and T = C₅ protons; Hutchins et al., 1972 ). Furthermore, the number and position of the signals in the ¹H-NMR spectrum are dependent on concentration, which was attributed to intermolecular chlorine-exchange mechanisms. Even though this parent class of six-membered NHPCls has been known for quite some time, no crystal structure analysis has thus far been reported. Herein, we present the crystal structure of the title compound that allows for a structural comparison with the most closely related four- or five-membered NHPCls known, on one hand, and with phospha- and 1,3,2-dioxaphosphacyclohexane derivatives, on the other hand.

2. Structural commentary

The molecular structure of 1 in the crystal is shown in Fig. 1. The molecule does not suffer from conformational disorder, which is often recognized in the solids of saturated N-heterocyclic compounds. The main characteristics of the molecule are: (i) the partially flattened chair conformation of the central six-membered heterocycle (displayed in more detail in Fig. 2) with an angle of 53.07 (15)° between the plane defined by the carbon atoms and the best plane of C1, C3, N1 and N2, and an angle of 27.96 (7)° between the latter plane and the plane defined by the nitrogen and phosphorus atoms; (ii) the equatorial orientation of both tert-butyl groups, enforced by the approximate trigonal–planar coordination of the nitrogen atoms [sums of angles 356.2 (N1) and 355.8 (N2)], in combination with the axial orientation of the chloro substituent (Fig. 2) [out of plane angle: 106.83 (5)°]; (iii) the length of the P1—Cl1 bond, 2.2869 (6) Å, is substantially longer than the standard single bond (2.02 Å; Brown, 2016 ) and the longest bond found in a six-membered NHPCl so far. The P—N bond lengths [P1—N1 = 1.6584 (14) and P1—N2 = 1.6519 (14) Å] are significantly smaller than the standard single-bond length [P—N = 1.704 (4) Å; Brown & Altermatt, 1985 ] and are close to the lower limit of the range found for NHPCls. The P—Cl bond is substantially longer than the P—Cl single-bond length in PCl₃ (2.034 Å; Galy & Enjalbert, 1982). The closest related five-membered NHPCl, 2-chloro-1,3-di-tert-butyl-2,1,3-phosphadiazolidine (CH₂N^tBu)₂>P–Cl shows almost identical bonding at the phosphorus atom [P—N = 1.652 (2) and P—Cl = 2.3136 (7) Å; Denk et al., 1999 ]. Unfortunately, a similar close relationship cannot be found among the known crystal structures of four-membered NHPCls and the closest related compound seems to be the P-chloro-substituted diazaphosphasiletidine Cl—P<(N^tBu)₂>SiMe₂ [P—N = 1.6815 (14) and P—Cl = 2.2498 (6) Å; Gün et al., 2017].

Figure 1
Diagram of the molecular structure of compound 1 in the crystal displaying the atom-labelling scheme. Anisotropic displacement ellipsoids are drawn at the 50% probability level, the radii of hydrogen atoms are chosen arbitrarily.

Figure 2
Chair conformation of the molecule (H atoms are omitted for clarity); note the cyclohexane-like conformation at the `carbon-atom side' [folding angle 53.07 (15)° as compared to 54.5 (6)° in the ordered, monoclinic phase of C₆H₁₂ (Kahn et al., 1973

)] and the `semi-flattened' conformation [folding angle 27.96 (7)°] at the `phosphorus/nitrogen-atom side'.

A more general comparison with other P-chloro-functionalized six-membered heterocyclic phosphorus compounds illustrates the P—Cl bond-length variation depending on the bonding situation in the heterocycle. Di-(3-methylindol-2-yl)chlorophosphine-4-bromophenylmethane (Mallov et al., 2012 ), exhibits a planar coordination at the two carbon atoms next to the nitrogen atoms due to exoalkylene group bonding, with a P—Cl bond length of only 2.108 (2) Å. In 2-chloro-1,3,5,7-tetramethyl-4,6,8-trioxa-2-phosphaadamantane (Downing et al., 2008 ), which can be considered as a chlorophosphorinane [(–CR)₂>P—Cl] with an enforced chair conformation, P—Cl = 2.0754 (11) Å and in the 2-chloro-1,3,2-dioxaphophorinane derivative [(–O)₂ >P—Cl] described by Pavan Kumar & Kumara Swamy (2007 ), P—Cl = 2.1227 (9) Å. Some examples of six-membered heterocycles with enforced ring flattening as a result of sterically demanding substituents (Brazeau et al., 2012; Burford et al., 2004 ; Holthausen et al., 2016 ; Schranz et al., 2000 ) and with flattening due to π-system involvement of the carbon atoms, such as 2-chloro-1,2,3,4-tetrahydro-1,3,2-diazaphosphinium salts (Lesikar et al., 2007 ; Vidovic et al., 2006 ), 2-chloro-5,6-benzo-1,3,2-diazaphosphorin-4-one (Sonnenburg et al., 1997 ) and 2-chloro-2,3-dihydro-1H-naphtho[1,8-de][1,3,2]diazaphosphinines (Kozma et al., 2015 ; Spinney et al., 2007 ) all show significantly shorter P—Cl bonds compared to 1, ranging from 2.072 (4) to 2.244 (3) Å. Further geometric details of 1 are given in the supporting information. C—C and C—N bond lengths, as well as endocyclic and exocyclic bond angles, are as expected taking into account the main structural characteristics given above. Finally it should be noted that the crystal structure determination described here confirms the suggestions of Hutchins et al. (1972) concerning the structure of 2-chloro-1,3,2-diazaphophorinanes, derived by NMR spectroscopy.

3. Supramolecular features

Inspection of the intermolecular distances gives no evidence for interactions stronger than van der Waals forces in the crystal of 1. The closest contact is given between Cl1 and the methylene group of the neighbouring molecule containing C1 at a Cl⋯C distance of 3.7134 (18) Å, symmetry related by the c glide plane (symmetry code: x, $[{1\over 2}]$ − y, $[{1\over 2}]$ + z). Fig. 3 shows the packing of the molecules in the crystal. Space group-symmetry gives rise to an appealing wave-like pattern.

Figure 3
Packing diagram of 1 (view direction [00 $[\overline{1}]$ ]) showing a wave-like pattern. Inspection of the intermolecular distances gives no evidence for interactions stronger than van der Waals forces and intermolecular influence on the P—Cl bonding can be excluded.

4. Database survey

A search of the Cambridge Structural Database (Version 5.40, November 2018 update; Groom et al., 2016 ) for the heterocycle substructure of 2-chloro-1,3,2-diazaphosphorinanes (i.e. exclusively single bonds in the six-membered ring) yielded only one structure (DEHZOH; Mallov et al., 2012). However, two of the ring carbon atoms are bonded to exoalkylene groups and are in planar coordination. A more general search allowing for alternative P^III-functionalization gave eight hits including N¹,N¹¹:N⁴,N⁸-bis(μ₂-methylphosphino)-1,4,8,11-tetraazacyclotetradecane (COLZUY; Hope et al., 1984 ), 1,3-di-tert-butyl-2-triphenylsilyl-1,3,2-diazaphosphorinane (DODDUV; Nifant'ev et al., 1985 ), the 1,3-di-tert-butyl-1,3,2-diazaphosphorinanyloxy)calix(4)arenes FEMLOZ and FEMLUF (Maslennikova et al., 2004 ), (η⁵-cyclopentadienyl)dichloro(1,3-dimethyl-1,3,2-diazaphospholyl)titanium (LARTED; Nifant'ev et al., 1991 ), the phosphatris(pyrrolyl)- and -(indolyl)methanes NEQBUG (Barnard & Mason, 2001a ) and YETDIK (Barnard & Mason, 2001b ) and finally 3-(tert-butyl)trimethylsilylamino-2,4-di-tert-butyl-1-[2-(1,3-di-tert-butyl-1,3,2-diazaphosphoridinyl)]imino-3-thio-1,2,4,3-thiadiazaphosphetidine (YOVYEN; Wrackmeyer et al., 1994 ). A search for P-chloro-functionalized six-membered ring compounds with any other three ring atoms joining the Cl—P<(NR)₂ fragment and allowing for any kind of bonding in the ring gave 16 hits including eight with three carbon atoms. In addition to DEHZOH mentioned before, these include 2-chloro-1-(2′-chloroethyl)-3-methyl-5,6-benzo-1,3,2-diazaphosphorin-4-one (MAMBUX; Sonnenburg et al., 1997), the 2-chloro-1,3-diorganyl-2,3-dihydro-1H-naphtho[1,8-de][1,3,2]diazaphosphinines OGOXAL (Kozma et al., 2015), REQKEE and TIPVIY (Spinney et al., 2007) and the 1,3-bis(2,6-di-isopropylphenyl)-2-chloro-1,2,3,4-tetrahydro-1,3,2-diazaphosphinium salts NIJXUA (Lesikar et al., 2007) and PENNUS (Vidovic et al., 2006).

5. Synthesis and crystallization

The title compound was prepared under an argon atmosphere in oven-dried glassware using standard Schlenk techniques, modifying a published procedure (Nifant'ev et al., 1977) by including a lithiation step. 3.75 g (20.1 mmol) of N,N′-di-tert-butyl-1,3-propanediamine were dissolved in a mixture of diethyl ether and n-hexane (35 ml/55 ml). 16 ml of an n-butyllithium solution (c = 2.5 mol l⁻¹ in n-hexane, 40 mmol) were slowly added at 263 K. Half an hour later, the reaction mixture was allowed to reach room temperature and the resulting pale-yellow suspension was stirred for 16 h. 2.92 g of PCl₃ (21.3 mmol) were added dropwise over a period of 15 minutes at 195 K. To complete the reaction, the yellow reaction mixture was stirred for another hour with cooling and finally for two h at room temperature. Subsequently, the LiCl precipitate was filtered off and, after removal of the solvent under reduced pressure, the crude product was obtained as a yellow solid. Colourless block-shaped crystals suitable for X-ray structure determination were obtained by sublimation in a vacuum (3·10⁻² mbar) at 313 K (30% yield; m.p. 327 K), by NMR analysis proved to be pure substance. ¹H-NMR (300 MHz, CDCl₃, 298 K) δ 3.16–3.07 (m, 4 H), 1.90–1.80 (m, 2 H), 1.34 [d, ⁴J(H,P) = 3.5 Hz, 18H].

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1. Positions of all hydrogen atoms were identified via subsequent ΔF syntheses. In the refinement, a riding model was applied using idealized C—H bond lengths (0.98–0.99 Å) as well as H—C—H and C—C—H angles. In addition, the H atoms of the CH₃ groups were allowed to rotate around the neighbouring C—C bonds. The U_iso values were set to 1.5U_eq(C_methyl) and 1.2U_eq(C_methylene).

Table 1
Experimental details

Crystal data
Chemical formula	C₁₁H₂₄ClN₂P
M_r	250.74
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	12.5954 (5), 9.1549 (3), 12.9614 (6)
β (°)	101.547 (3)
V (Å³)	1464.33 (10)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.35
Crystal size (mm)	0.48 × 0.28 × 0.25

Data collection
Diffractometer	Stoe IPDS II
Absorption correction	Multi-scan (XPREP; Bruker, 2008 )
T_min, T_max	0.761, 0.929
No. of measured, independent and observed [I > 2σ(I)] reflections	16291, 3943, 3547
R_int	0.050
(sin θ/λ)_max (Å⁻¹)	0.686

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.109, 1.01
No. of reflections	3943
No. of parameters	142
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.41, −0.21
Computer programs: X-AREA (Stoe & Cie, 2002 ), SHELXT (Sheldrick, 2015a ), SHELXL2014 (Sheldrick, 2015b ) and DIAMOND (Brandenburg, 2015 ).

Supporting information

CCDC reference: 1906304

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989019004195/pk2615sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989019004195/pk2615Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989019004195/pk2615Isup3.cml

checkCIF report

Computing details top

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA (Stoe & Cie, 2002); data reduction: X-AREA (Stoe & Cie, 2002); program(s) used to solve structure: SHELXT (Sheldrick, 2015a4); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg, 2015); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015b).

1,3-Di-tert-butyl-2-chloro-1,3,2-diazaphosphinane top

Crystal data top

C₁₁H₂₄ClN₂P	F(000) = 544
M_r = 250.74	D_x = 1.137 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 12.5954 (5) Å	Cell parameters from 20870 reflections
b = 9.1549 (3) Å	θ = 4.5–59.2°
c = 12.9614 (6) Å	µ = 0.35 mm⁻¹
β = 101.547 (3)°	T = 173 K
V = 1464.33 (10) Å³	Block, colourless
Z = 4	0.48 × 0.28 × 0.25 mm

Data collection top

Stoe IPDS II diffractometer	3547 reflections with I > 2σ(I)
ω–scans	R_int = 0.050
Absorption correction: multi-scan (XPREP; Bruker, 2008)	θ_max = 29.2°, θ_min = 2.7°
T_min = 0.761, T_max = 0.929	h = −17→17
16291 measured reflections	k = −12→12
3943 independent reflections	l = −17→17

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.048	Hydrogen site location: difference Fourier map
wR(F²) = 0.109	H-atom parameters constrained
S = 1.01	w = 1/[σ²(F_o²) + (0.0327P)² + 0.8644P] where P = (F_o² + 2F_c²)/3
3943 reflections	(Δ/σ)_max = 0.001
142 parameters	Δρ_max = 0.41 e Å⁻³
0 restraints	Δρ_min = −0.21 e Å⁻³

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	0.85529 (4)	0.26976 (5)	0.83702 (4)	0.05736 (15)
P1	0.72874 (3)	0.09412 (5)	0.77742 (3)	0.03774 (11)
N1	0.67636 (11)	0.15879 (16)	0.65862 (11)	0.0411 (3)
N2	0.80820 (11)	−0.03915 (15)	0.75215 (11)	0.0390 (3)
C1	0.73831 (16)	0.1599 (2)	0.57350 (14)	0.0511 (4)
H11	0.7950	0.2362	0.5881	0.061*
H12	0.6892	0.1842	0.5060	0.061*
C2	0.79040 (18)	0.0142 (3)	0.56389 (15)	0.0579 (5)
H21	0.7332	−0.0608	0.5451	0.070*
H22	0.8314	0.0187	0.5063	0.070*
C3	0.86546 (15)	−0.0296 (2)	0.66384 (14)	0.0485 (4)
H31	0.8981	−0.1256	0.6538	0.058*
H32	0.9248	0.0428	0.6809	0.058*
C4	0.58516 (16)	0.2663 (2)	0.64533 (15)	0.0507 (4)
C5	0.6238 (2)	0.4171 (3)	0.6188 (2)	0.0810 (7)
H51	0.6437	0.4141	0.5495	0.122*
H52	0.6870	0.4457	0.6722	0.122*
H53	0.5654	0.4883	0.6176	0.122*
C6	0.49516 (19)	0.2120 (3)	0.5566 (2)	0.0804 (8)
H61	0.5245	0.1962	0.4930	0.121*
H62	0.4372	0.2850	0.5423	0.121*
H63	0.4660	0.1199	0.5777	0.121*
C7	0.5396 (2)	0.2788 (3)	0.7459 (2)	0.0756 (7)
H71	0.5958	0.3169	0.8030	0.113*
H72	0.5165	0.1822	0.7653	0.113*
H73	0.4774	0.3454	0.7337	0.113*
C8	0.85809 (15)	−0.1413 (2)	0.83911 (15)	0.0489 (4)
C9	0.97954 (16)	−0.1119 (3)	0.87176 (17)	0.0655 (6)
H91	1.0154	−0.1390	0.8141	0.098*
H92	1.0096	−0.1700	0.9343	0.098*
H93	0.9915	−0.0079	0.8879	0.098*
C10	0.8368 (3)	−0.2973 (2)	0.7984 (2)	0.0860 (8)
H101	0.7585	−0.3146	0.7800	0.129*
H102	0.8699	−0.3664	0.8533	0.129*
H103	0.8684	−0.3110	0.7359	0.129*
C11	0.80696 (18)	−0.1203 (3)	0.93605 (17)	0.0631 (6)
H111	0.7286	−0.1367	0.9164	0.095*
H112	0.8208	−0.0205	0.9629	0.095*
H113	0.8388	−0.1902	0.9908	0.095*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0692 (3)	0.0498 (3)	0.0529 (3)	−0.0125 (2)	0.0117 (2)	−0.0122 (2)
P1	0.0374 (2)	0.0386 (2)	0.0394 (2)	0.00313 (16)	0.01304 (15)	0.00418 (16)
N1	0.0410 (7)	0.0420 (7)	0.0407 (7)	0.0073 (6)	0.0093 (5)	0.0033 (6)
N2	0.0388 (7)	0.0362 (6)	0.0423 (7)	0.0030 (5)	0.0093 (5)	0.0012 (5)
C1	0.0553 (10)	0.0609 (11)	0.0386 (8)	0.0111 (9)	0.0133 (7)	0.0070 (8)
C2	0.0666 (12)	0.0672 (13)	0.0426 (9)	0.0142 (10)	0.0169 (9)	−0.0053 (9)
C3	0.0493 (9)	0.0537 (10)	0.0451 (9)	0.0109 (8)	0.0158 (7)	−0.0028 (8)
C4	0.0511 (10)	0.0481 (10)	0.0529 (10)	0.0149 (8)	0.0106 (8)	0.0062 (8)
C5	0.101 (2)	0.0493 (12)	0.0943 (18)	0.0181 (13)	0.0239 (15)	0.0167 (12)
C6	0.0526 (12)	0.098 (2)	0.0830 (16)	0.0202 (13)	−0.0058 (11)	−0.0045 (15)
C7	0.0733 (15)	0.0876 (17)	0.0719 (14)	0.0409 (14)	0.0291 (12)	0.0144 (13)
C8	0.0512 (10)	0.0434 (9)	0.0522 (10)	0.0103 (8)	0.0110 (8)	0.0108 (8)
C9	0.0477 (10)	0.0957 (17)	0.0521 (11)	0.0230 (11)	0.0076 (8)	0.0079 (11)
C10	0.115 (2)	0.0402 (11)	0.102 (2)	0.0101 (13)	0.0214 (17)	0.0085 (12)
C11	0.0636 (12)	0.0692 (13)	0.0612 (12)	0.0141 (10)	0.0234 (10)	0.0278 (10)

Geometric parameters (Å, º) top

Cl1—P1	2.2869 (6)	C5—H53	0.9800
P1—N2	1.6519 (14)	C6—H61	0.9800
P1—N1	1.6584 (14)	C6—H62	0.9800
N1—C1	1.473 (2)	C6—H63	0.9800
N1—C4	1.496 (2)	C7—H71	0.9800
N2—C3	1.472 (2)	C7—H72	0.9800
N2—C8	1.502 (2)	C7—H73	0.9800
C1—C2	1.502 (3)	C8—C10	1.527 (3)
C1—H11	0.9900	C8—C9	1.527 (3)
C1—H12	0.9900	C8—C11	1.534 (3)
C2—C3	1.498 (3)	C9—H91	0.9800
C2—H21	0.9900	C9—H92	0.9800
C2—H22	0.9900	C9—H93	0.9800
C3—H31	0.9900	C10—H101	0.9800
C3—H32	0.9900	C10—H102	0.9800
C4—C5	1.526 (3)	C10—H103	0.9800
C4—C6	1.527 (3)	C11—H111	0.9800
C4—C7	1.529 (3)	C11—H112	0.9800
C5—H51	0.9800	C11—H113	0.9800
C5—H52	0.9800

N2—P1—N1	102.93 (7)	H52—C5—H53	109.5
N2—P1—Cl1	100.22 (5)	C4—C6—H61	109.5
N1—P1—Cl1	100.57 (6)	C4—C6—H62	109.5
C1—N1—C4	114.76 (14)	H61—C6—H62	109.5
C1—N1—P1	121.73 (11)	C4—C6—H63	109.5
C4—N1—P1	119.69 (12)	H61—C6—H63	109.5
C3—N2—C8	115.07 (13)	H62—C6—H63	109.5
C3—N2—P1	121.39 (12)	C4—C7—H71	109.5
C8—N2—P1	119.34 (11)	C4—C7—H72	109.5
N1—C1—C2	111.20 (16)	H71—C7—H72	109.5
N1—C1—H11	109.4	C4—C7—H73	109.5
C2—C1—H11	109.4	H71—C7—H73	109.5
N1—C1—H12	109.4	H72—C7—H73	109.5
C2—C1—H12	109.4	N2—C8—C10	107.76 (17)
H11—C1—H12	108.0	N2—C8—C9	110.10 (16)
C3—C2—C1	112.13 (16)	C10—C8—C9	110.9 (2)
C3—C2—H21	109.2	N2—C8—C11	110.81 (15)
C1—C2—H21	109.2	C10—C8—C11	109.06 (19)
C3—C2—H22	109.2	C9—C8—C11	108.19 (17)
C1—C2—H22	109.2	C8—C9—H91	109.5
H21—C2—H22	107.9	C8—C9—H92	109.5
N2—C3—C2	111.45 (15)	H91—C9—H92	109.5
N2—C3—H31	109.3	C8—C9—H93	109.5
C2—C3—H31	109.3	H91—C9—H93	109.5
N2—C3—H32	109.3	H92—C9—H93	109.5
C2—C3—H32	109.3	C8—C10—H101	109.5
H31—C3—H32	108.0	C8—C10—H102	109.5
N1—C4—C5	110.44 (17)	H101—C10—H102	109.5
N1—C4—C6	108.04 (17)	C8—C10—H103	109.5
C5—C4—C6	110.3 (2)	H101—C10—H103	109.5
N1—C4—C7	111.19 (15)	H102—C10—H103	109.5
C5—C4—C7	108.4 (2)	C8—C11—H111	109.5
C6—C4—C7	108.5 (2)	C8—C11—H112	109.5
C4—C5—H51	109.5	H111—C11—H112	109.5
C4—C5—H52	109.5	C8—C11—H113	109.5
H51—C5—H52	109.5	H111—C11—H113	109.5
C4—C5—H53	109.5	H112—C11—H113	109.5
H51—C5—H53	109.5

N2—P1—N1—C1	−33.19 (16)	C1—C2—C3—N2	59.3 (2)
Cl1—P1—N1—C1	69.98 (15)	C1—N1—C4—C5	−48.7 (2)
N2—P1—N1—C4	170.01 (13)	P1—N1—C4—C5	109.66 (18)
Cl1—P1—N1—C4	−86.82 (14)	C1—N1—C4—C6	72.0 (2)
N1—P1—N2—C3	33.52 (15)	P1—N1—C4—C6	−129.63 (17)
Cl1—P1—N2—C3	−69.94 (13)	C1—N1—C4—C7	−169.02 (19)
N1—P1—N2—C8	−170.64 (13)	P1—N1—C4—C7	−10.7 (2)
Cl1—P1—N2—C8	85.90 (13)	C3—N2—C8—C10	−72.3 (2)
C4—N1—C1—C2	−153.99 (17)	P1—N2—C8—C10	130.43 (17)
P1—N1—C1—C2	48.1 (2)	C3—N2—C8—C9	48.8 (2)
N1—C1—C2—C3	−58.7 (2)	P1—N2—C8—C9	−108.48 (16)
C8—N2—C3—C2	154.03 (17)	C3—N2—C8—C11	168.49 (17)
P1—N2—C3—C2	−49.2 (2)	P1—N2—C8—C11	11.2 (2)

Acknowledgements

We thank E. Hammes for technical support.

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