organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 9| September 2014| Pages o889-o890

Crystal structure of N,N′-bis­­(diiso­propyl­phosphan­yl)-4-methyl­pyridine-2,6-di­amine

aInstitute for Chemical Technologies and Analytics, Division of Structural Chemistry, Vienna University of Technology, Getreidemarkt 9/164-SC, A-1060 Vienna, Austria, and bInstitute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163, A-1060 Vienna, Austria
*Correspondence e-mail: mweil@mail.zserv.tuwien.ac.at

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 12 April 2014; accepted 13 April 2014; online 1 August 2014)

In the mol­ecule of the title compound, C18H35N3P2, the methyl­pyridine-2,6-di­amine moiety is almost planar, with a maximum deviation of 0.0129 (9) Å for one of the amine N atoms. Whereas one of the P atoms is co-planar with this mean plane [deviation = 0.0158 (10) Å], the other P atom is considerably displaced out of the mean plane by 0.5882 (10) Å. In the crystal, no directional intermolecular interactions beyond van der Waals contacts could be identified.

1. Related literature

The title compound belongs to the family of PNP pincer ligands that are capable of forming complexes with various transition metals, leading to inter­esting properties and applications, see: Benito-Garagorri & Kirchner (2008[Benito-Garagorri, D. & Kirchner, K. (2008). Acc. Chem. Res. 41, 201-213.]); Langer et al. (2011[Langer, R., Leitus, G., Ben-David, Y. & Milstein, D. (2011). Angew. Chem. Int. Ed. Engl. 50, 2120-2124.]); Bichler et al. (2013[Bichler, B., Holzhacker, C., Stöger, B., Puchberger, M., Veiros, L. F. & Kirchner, K. (2013). Organometallics, 32, 4114-4121.]). For general aspects of pincer ligands and derived complexes, see: Morales-Morales & Jensen (2007[Morales-Morales, D. & Jensen, C. (2007). The Chemistry of Pincer Compounds. Amsterdam: Elsevier Science.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C18H35N3P2

  • Mr = 355.4

  • Orthorhombic, P b c a

  • a = 14.3394 (12) Å

  • b = 10.0089 (16) Å

  • c = 29.562 (3) Å

  • V = 4242.9 (9) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.21 mm−1

  • T = 100 K

  • 0.70 × 0.28 × 0.04 mm

2.2. Data collection

  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2013[Bruker (2013). APEX2, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.93, Tmax = 0.99

  • 149837 measured reflections

  • 6241 independent reflections

  • 4614 reflections with I > 3σ(I)

  • Rint = 0.066

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.031

  • wR(F2) = 0.046

  • S = 1.39

  • 6241 reflections

  • 216 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.21 e Å−3

Data collection: APEX2 (Bruker, 2013[Bruker (2013). APEX2, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2013[Bruker (2013). APEX2, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus; program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007[Palatinus, L. & Chapuis, G. (2007). J. Appl. Cryst. 40, 786-790.]); program(s) used to refine structure: JANA2006 (Petříček, et al., 2014[Petříček, V., Dušek, M. & Palatinus, L. (2014). Z. Kristallogr. 229, 345-352.]); molecular graphics: Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Related literature top

The title compound belongs to the family of PNP pincer ligands that are capable of forming complexes with various transition metals, leading to interesting properties and applications, see: Benito-Garagorri & Kirchner (2008); Langer et al. (2011); Bichler et al. (2013). For general aspects of pincer ligands and derived complexes, see: Morales-Morales & Jensen (2007).

Experimental top

4-Methylpyridine-2,6-diamine (500 mg, 4 mmol, 1 eq) was diluted in toluene and triethylamine (1.2 ml, 8.6 mmol, 2.1 eq) was added. The mixture was cooled to 273 K using an ice bath and chlorodiisopropylphosphine (1.3 ml, 8.2 mmol, 2.05 eq) was added drop wise using a syringe. The cooling bath was removed, and after reaching room temperature, the reaction mixture was stirred at 353 K for another 12 h. The precipitate was filtered off and the solvent was evaporated. Yield: 69% off-white powder. For further purification, the compound was recrystallized using a toluene/hexane 1:1 (v/v) mixture. Spectroscopic data for the title compound are available in the archived CIF.

Refinement top

The H atoms of the amine groups were located in difference Fourier maps and the N—H distances restrained to 0.87 Å. The remaining H atoms were placed geometrically and refined as riding on the parent C atoms with Uiso(H) =1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2013); cell refinement: SAINT-Plus (Bruker, 2013); data reduction: SAINT-Plus (Bruker, 2013); program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007); program(s) used to refine structure: JANA2006 (Petříček, et al., 2014); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 80% probability level.
N,N'-Bis(diisopropylphosphanyl)-4-methylpyridine-2,6-diamine top
Crystal data top
C18H35N3P2F(000) = 1552
Mr = 355.4Dx = 1.113 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 9974 reflections
a = 14.3394 (12) Åθ = 2.5–30°
b = 10.0089 (16) ŵ = 0.21 mm1
c = 29.562 (3) ÅT = 100 K
V = 4242.9 (9) Å3Plate, translucent colourless
Z = 80.70 × 0.28 × 0.04 mm
Data collection top
Bruker APEXII CCD
diffractometer
6241 independent reflections
Radiation source: X-ray tube4614 reflections with I > 3σ(I)
Graphite monochromatorRint = 0.066
ω and ϕ scansθmax = 30.1°, θmin = 1.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2013)
h = 2020
Tmin = 0.93, Tmax = 0.99k = 1414
149837 measured reflectionsl = 4141
Refinement top
Refinement on FPrimary atom site location: iterative
R[F2 > 2σ(F2)] = 0.031Secondary atom site location: none
wR(F2) = 0.046Hydrogen site location: geom,difmap
S = 1.39H atoms treated by a mixture of independent and constrained refinement
6241 reflectionsWeighting scheme based on measured s.u.'s w = 1/(σ2(F) + 0.0004F2)
216 parameters(Δ/σ)max = 0.014
2 restraintsΔρmax = 0.29 e Å3
132 constraintsΔρmin = 0.21 e Å3
Crystal data top
C18H35N3P2V = 4242.9 (9) Å3
Mr = 355.4Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 14.3394 (12) ŵ = 0.21 mm1
b = 10.0089 (16) ÅT = 100 K
c = 29.562 (3) Å0.70 × 0.28 × 0.04 mm
Data collection top
Bruker APEXII CCD
diffractometer
6241 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2013)
4614 reflections with I > 3σ(I)
Tmin = 0.93, Tmax = 0.99Rint = 0.066
149837 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0312 restraints
wR(F2) = 0.046H atoms treated by a mixture of independent and constrained refinement
S = 1.39Δρmax = 0.29 e Å3
6241 reflectionsΔρmin = 0.21 e Å3
216 parameters
Special details top

Experimental. Spectroscopic data for the title compound:

1H-NMR (400 MHz, CDCl3) 6.34 (s, 2H), 4.88 (bs, 2H), 2.18 (s, 3H), 1.87–1.60 (m, 4H), 1.15–0.92 (m, 24H). 31P NMR (162 MHz, CDCl3) 55.65. 13C-NMR (63 MHz, CDCl3) 156.59 (d, J = 21.9 Hz), 153.94 (s), 99.14 (d, J = 19.7 Hz), 26.27 (d, J = 11.4 Hz), 21.80 (d, J = 15.3 Hz), 18.46 (d, J = 19.7 Hz), 17.18 (d, J = 7.9 Hz).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
P10.781952 (19)0.61761 (3)0.277629 (10)0.01628 (8)
P20.62798 (2)0.33177 (3)0.045775 (10)0.01837 (8)
N10.70180 (6)0.42925 (9)0.16952 (3)0.0149 (2)
N20.73728 (7)0.50053 (10)0.24153 (3)0.0176 (3)
N30.66959 (7)0.33964 (10)0.10001 (3)0.0200 (3)
C10.69814 (7)0.52954 (11)0.19953 (4)0.0146 (3)
C20.65663 (7)0.65213 (11)0.19012 (4)0.0166 (3)
C30.61705 (7)0.67148 (11)0.14781 (4)0.0164 (3)
C40.62017 (8)0.56884 (11)0.11637 (4)0.0180 (3)
C50.66312 (7)0.44882 (11)0.12890 (4)0.0158 (3)
C60.57228 (8)0.80360 (11)0.13652 (4)0.0220 (3)
C70.76791 (8)0.52642 (12)0.33135 (4)0.0211 (3)
C80.66449 (9)0.50783 (15)0.34168 (5)0.0326 (4)
C90.81669 (11)0.60387 (14)0.36929 (4)0.0321 (4)
C100.90932 (8)0.60456 (12)0.26658 (4)0.0207 (3)
C110.92671 (9)0.64908 (13)0.21773 (4)0.0280 (4)
C120.95354 (8)0.46787 (12)0.27535 (4)0.0251 (3)
C130.71074 (8)0.20717 (12)0.02331 (4)0.0196 (3)
C140.80702 (9)0.27110 (14)0.01819 (4)0.0304 (4)
C150.67652 (9)0.15302 (14)0.02210 (4)0.0288 (4)
C160.51998 (8)0.23173 (12)0.05297 (4)0.0218 (3)
C170.44882 (9)0.31763 (15)0.07830 (5)0.0322 (4)
C180.53214 (9)0.09667 (13)0.07581 (4)0.0285 (4)
H1c20.6554170.7217980.2124360.0199*
H1c40.5935870.5797670.0867950.0216*
H1c60.5315260.8297370.1607150.0264*
H2c60.6197910.8701550.1325750.0264*
H3c60.5369970.7950350.1090710.0264*
H1c70.7959330.4395910.3289920.0253*
H1c80.6348850.4631140.3167960.0392*
H2c80.6575850.45510.3685980.0392*
H3c80.6359190.5935580.3461450.0392*
H1c90.881550.6142210.3620350.0386*
H2c90.7884160.6903180.3724020.0386*
H3c90.8106760.5555820.3971930.0386*
H1c100.9395050.6615230.2882210.0248*
H1c110.8976220.7341810.2127030.0336*
H2c110.9925970.6566070.2125560.0336*
H3c110.9008230.5843590.1973190.0336*
H1c120.9502310.4476570.3070530.0302*
H2c120.9205250.4007940.2585480.0302*
H3c121.0176120.4694080.2659480.0302*
H1c130.7149960.1336650.0440670.0235*
H1c140.8236370.3154440.0458390.0365*
H2c140.8522430.2031240.0115830.0365*
H3c140.8056350.3348840.0060510.0365*
H1c150.6201480.1030250.01760.0345*
H2c150.6645770.2261330.0423060.0345*
H3c150.7233560.0958830.0349220.0345*
H1c160.4988080.2088670.0231470.0262*
H1c170.4401360.4004660.0624770.0386*
H2c170.3904610.2709030.0800080.0386*
H3c170.4712180.3354230.1083020.0386*
H1c180.5696130.0398460.0569950.0343*
H2c180.5623480.1086170.1045090.0343*
H3c180.4721360.0562970.0803520.0343*
H1n30.6939 (10)0.2689 (9)0.1124 (5)0.042 (4)*
H1n20.7548 (9)0.4176 (4)0.2438 (5)0.027 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
P10.01745 (13)0.01506 (14)0.01634 (13)0.00115 (10)0.00312 (10)0.00393 (11)
P20.02390 (15)0.01747 (15)0.01375 (13)0.00096 (11)0.00236 (10)0.00068 (11)
N10.0140 (4)0.0141 (4)0.0165 (4)0.0004 (3)0.0013 (3)0.0016 (3)
N20.0208 (5)0.0137 (4)0.0182 (4)0.0012 (4)0.0056 (4)0.0025 (4)
N30.0287 (5)0.0153 (5)0.0160 (4)0.0045 (4)0.0058 (4)0.0028 (4)
C10.0112 (4)0.0159 (5)0.0167 (5)0.0022 (4)0.0006 (4)0.0010 (4)
C20.0156 (5)0.0141 (5)0.0199 (5)0.0001 (4)0.0007 (4)0.0034 (4)
C30.0139 (5)0.0135 (5)0.0217 (5)0.0003 (4)0.0000 (4)0.0010 (4)
C40.0207 (5)0.0163 (5)0.0170 (5)0.0016 (4)0.0031 (4)0.0002 (4)
C50.0156 (5)0.0155 (5)0.0162 (5)0.0014 (4)0.0003 (4)0.0020 (4)
C60.0239 (6)0.0168 (5)0.0253 (6)0.0045 (4)0.0025 (4)0.0002 (5)
C70.0249 (6)0.0211 (6)0.0171 (5)0.0032 (4)0.0013 (4)0.0022 (4)
C80.0296 (6)0.0423 (8)0.0260 (6)0.0022 (6)0.0067 (5)0.0028 (6)
C90.0461 (8)0.0318 (7)0.0185 (6)0.0040 (6)0.0077 (5)0.0039 (5)
C100.0177 (5)0.0183 (6)0.0260 (6)0.0018 (4)0.0031 (4)0.0044 (5)
C110.0260 (6)0.0249 (6)0.0332 (7)0.0011 (5)0.0065 (5)0.0012 (5)
C120.0182 (5)0.0240 (6)0.0332 (7)0.0018 (4)0.0041 (5)0.0020 (5)
C130.0227 (5)0.0198 (5)0.0161 (5)0.0014 (4)0.0030 (4)0.0015 (4)
C140.0269 (6)0.0341 (8)0.0301 (7)0.0059 (5)0.0072 (5)0.0027 (6)
C150.0374 (7)0.0300 (7)0.0189 (6)0.0014 (6)0.0031 (5)0.0060 (5)
C160.0192 (5)0.0272 (6)0.0191 (5)0.0018 (5)0.0018 (4)0.0049 (5)
C170.0242 (6)0.0400 (8)0.0323 (7)0.0051 (6)0.0006 (5)0.0097 (6)
C180.0271 (6)0.0282 (7)0.0303 (7)0.0062 (5)0.0044 (5)0.0002 (5)
Geometric parameters (Å, º) top
P1—N21.7094 (10)C9—H2c90.96
P1—C71.8426 (12)C9—H3c90.96
P1—C101.8599 (12)C10—C111.5319 (18)
P2—N31.7125 (11)C10—C121.5300 (17)
P2—C131.8452 (12)C10—H1c100.96
P2—C161.8564 (12)C11—H1c110.96
N1—C11.3408 (14)C11—H2c110.96
N1—C51.3372 (14)C11—H3c110.96
N2—C11.3932 (14)C12—H1c120.96
N2—H1n20.870 (6)C12—H2c120.96
N3—C51.3901 (15)C12—H3c120.96
N3—H1n30.870 (11)C13—C141.5292 (18)
C1—C21.3918 (16)C13—C151.5286 (17)
C2—C31.3872 (16)C13—H1c130.96
C2—H1c20.96C14—H1c140.96
C3—C41.3861 (16)C14—H2c140.96
C3—C61.5074 (16)C14—H3c140.96
C4—C51.3998 (16)C15—H1c150.96
C4—H1c40.96C15—H2c150.96
C6—H1c60.96C15—H3c150.96
C6—H2c60.96C16—C171.5301 (18)
C6—H3c60.96C16—C181.5212 (18)
C7—C81.5256 (17)C16—H1c160.96
C7—C91.5324 (18)C17—H1c170.96
C7—H1c70.96C17—H2c170.96
C8—H1c80.96C17—H3c170.96
C8—H2c80.96C18—H1c180.96
C8—H3c80.96C18—H2c180.96
C9—H1c90.96C18—H3c180.96
N2—P1—C799.06 (5)P1—C10—C12116.11 (8)
N2—P1—C10102.14 (5)P1—C10—H1c10106.5
C7—P1—C10102.93 (5)C11—C10—C12110.63 (10)
N3—P2—C1398.28 (5)C11—C10—H1c10112.45
N3—P2—C16102.02 (5)C12—C10—H1c10103.38
C13—P2—C16102.31 (5)C10—C11—H1c11109.47
C1—N1—C5117.93 (9)C10—C11—H2c11109.47
P1—N2—C1124.36 (8)C10—C11—H3c11109.47
P1—N2—H1n2119.8 (9)H1c11—C11—H2c11109.47
C1—N2—H1n2112.7 (9)H1c11—C11—H3c11109.47
P2—N3—C5126.02 (8)H2c11—C11—H3c11109.47
P2—N3—H1n3119.7 (9)C10—C12—H1c12109.47
C5—N3—H1n3114.1 (9)C10—C12—H2c12109.47
N1—C1—N2114.71 (9)C10—C12—H3c12109.47
N1—C1—C2122.99 (10)H1c12—C12—H2c12109.47
N2—C1—C2122.29 (10)H1c12—C12—H3c12109.47
C1—C2—C3118.57 (10)H2c12—C12—H3c12109.47
C1—C2—H1c2120.71P2—C13—C14109.48 (9)
C3—C2—H1c2120.71P2—C13—C15110.44 (8)
C2—C3—C4119.21 (10)P2—C13—H1c13109.19
C2—C3—C6119.76 (10)C14—C13—C15110.57 (10)
C4—C3—C6121.02 (10)C14—C13—H1c13109.06
C3—C4—C5118.21 (10)C15—C13—H1c13108.06
C3—C4—H1c4120.89C13—C14—H1c14109.47
C5—C4—H1c4120.89C13—C14—H2c14109.47
N1—C5—N3114.13 (9)C13—C14—H3c14109.47
N1—C5—C4123.08 (10)H1c14—C14—H2c14109.47
N3—C5—C4122.78 (10)H1c14—C14—H3c14109.47
C3—C6—H1c6109.47H2c14—C14—H3c14109.47
C3—C6—H2c6109.47C13—C15—H1c15109.47
C3—C6—H3c6109.47C13—C15—H2c15109.47
H1c6—C6—H2c6109.47C13—C15—H3c15109.47
H1c6—C6—H3c6109.47H1c15—C15—H2c15109.47
H2c6—C6—H3c6109.47H1c15—C15—H3c15109.47
P1—C7—C8109.83 (8)H2c15—C15—H3c15109.47
P1—C7—C9109.29 (8)P2—C16—C17108.02 (9)
P1—C7—H1c7109.89P2—C16—C18115.76 (8)
C8—C7—C9111.03 (10)P2—C16—H1c16106.69
C8—C7—H1c7108.11C17—C16—C18111.01 (10)
C9—C7—H1c7108.66C17—C16—H1c16111.87
C7—C8—H1c8109.47C18—C16—H1c16103.42
C7—C8—H2c8109.47C16—C17—H1c17109.47
C7—C8—H3c8109.47C16—C17—H2c17109.47
H1c8—C8—H2c8109.47C16—C17—H3c17109.47
H1c8—C8—H3c8109.47H1c17—C17—H2c17109.47
H2c8—C8—H3c8109.47H1c17—C17—H3c17109.47
C7—C9—H1c9109.47H2c17—C17—H3c17109.47
C7—C9—H2c9109.47C16—C18—H1c18109.47
C7—C9—H3c9109.47C16—C18—H2c18109.47
H1c9—C9—H2c9109.47C16—C18—H3c18109.47
H1c9—C9—H3c9109.47H1c18—C18—H2c18109.47
H2c9—C9—H3c9109.47H1c18—C18—H3c18109.47
P1—C10—C11107.76 (8)H2c18—C18—H3c18109.47

Experimental details

Crystal data
Chemical formulaC18H35N3P2
Mr355.4
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)100
a, b, c (Å)14.3394 (12), 10.0089 (16), 29.562 (3)
V3)4242.9 (9)
Z8
Radiation typeMo Kα
µ (mm1)0.21
Crystal size (mm)0.70 × 0.28 × 0.04
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2013)
Tmin, Tmax0.93, 0.99
No. of measured, independent and
observed [I > 3σ(I)] reflections
149837, 6241, 4614
Rint0.066
(sin θ/λ)max1)0.706
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.031, 0.046, 1.39
No. of reflections6241
No. of parameters216
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.29, 0.21

Computer programs: APEX2 (Bruker, 2013), SAINT-Plus (Bruker, 2013), SUPERFLIP (Palatinus & Chapuis, 2007), JANA2006 (Petříček, et al., 2014), Mercury (Macrae et al., 2008), publCIF (Westrip, 2010).

 

Acknowledgements

The X-ray centre of the Vienna University of Technology is acknowledged for providing access to the single-crystal diffractometer.

References

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ISSN: 2056-9890
Volume 70| Part 9| September 2014| Pages o889-o890
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