Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270100000391/qb0151sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270100000391/qb0151Isup2.hkl |
CCDC reference: 142929
The title compound (I) was prepared following a previously published procedure (Saleem & Hodali, 1990). A suspension of the dichloride complex [Pd(dppp)Cl2] (2.0 g, 3.39 mmol) in dry diethyl ether (50 ml) was cooled to 273 K. Methyl lithium solution (1.6 M, 17 mmol) was added dropwise within 30 min. The mixture was then allowed to warm up to room temperature, and treated at 273 K with saturated aqueous NH4Cl (50 ml). The ether layer was separated and dried over MgSO4. The filtrate was evaporated to dryness to give a white microcrystalline solid. Recrystallization from toluene yielded colourless crystals suitable for X-ray analysis (total yield 1.50 g, 81%).
The measured intensities were corrected for Lorentz and polarization effects. The structure was solved by direct methods using XMY program package (Debaerdemaeker, 1993). All non-H atoms were refined anisotropically. H atoms were positioned geometrically and their displacement factors were set at 1.2 times the isotropic factor for the host atom.
Data collection: IDPS (Stoe & Cie, 1997)); cell refinement: IDPS; data reduction: IDPS; program(s) used to solve structure: XMY93 (Debaermaeker, 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).
[Pd(CH3)2(C27H26P2)]·0.5C7H8 | F(000) = 1228 |
Mr = 594.95 | Dx = 1.329 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 12.260 (3) Å | Cell parameters from 4521 reflections |
b = 15.025 (2) Å | θ = 2.2–24.1° |
c = 16.347 (3) Å | µ = 0.75 mm−1 |
β = 99.00 (2)° | T = 293 K |
V = 2974.2 (10) Å3 | Prism, colourless |
Z = 4 | 0.45 × 0.40 × 0.35 mm |
Stoe-IPDS image-plate diffractometer | 3825 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.034 |
Graphite monochromator | θmax = 24.1°, θmin = 2.2° |
Detector resolution: 0.15 pixels mm-1 | h = −13→14 |
rotation scans | k = −16→16 |
22466 measured reflections | l = −18→18 |
4521 independent reflections |
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)] = 0.023 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.062 | H-atom parameters constrained |
S = 1.04 | Calculated w = 1/[σ2(Fo2) + (0.0393P)2 + 0.220P] where P = (Fo2 + 2Fc2)/3 |
4521 reflections | (Δ/σ)max = 0.002 |
355 parameters | Δρmax = 0.28 e Å−3 |
55 restraints | Δρmin = −0.20 e Å−3 |
[Pd(CH3)2(C27H26P2)]·0.5C7H8 | V = 2974.2 (10) Å3 |
Mr = 594.95 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 12.260 (3) Å | µ = 0.75 mm−1 |
b = 15.025 (2) Å | T = 293 K |
c = 16.347 (3) Å | 0.45 × 0.40 × 0.35 mm |
β = 99.00 (2)° |
Stoe-IPDS image-plate diffractometer | 3825 reflections with I > 2σ(I) |
22466 measured reflections | Rint = 0.034 |
4521 independent reflections | θmax = 24.1° |
R[F2 > 2σ(F2)] = 0.023 | 55 restraints |
wR(F2) = 0.062 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.28 e Å−3 |
4521 reflections | Δρmin = −0.20 e Å−3 |
355 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Pd1 | 0.112737 (13) | 0.626486 (12) | 0.218962 (9) | 0.04119 (7) | |
P1 | 0.04181 (5) | 0.56046 (5) | 0.32618 (3) | 0.04852 (16) | |
P2 | 0.24781 (5) | 0.51983 (4) | 0.21929 (3) | 0.04253 (14) | |
C1 | 0.1380 (2) | 0.4962 (2) | 0.40105 (14) | 0.0627 (7) | |
H1A | 0.1919 | 0.5375 | 0.4326 | 0.075* | |
H1B | 0.0961 | 0.4673 | 0.4409 | 0.075* | |
C2 | 0.2003 (2) | 0.42523 (19) | 0.36082 (14) | 0.0582 (7) | |
H2A | 0.1470 | 0.3920 | 0.3203 | 0.070* | |
H2B | 0.2330 | 0.3826 | 0.4040 | 0.070* | |
C3 | 0.29190 (19) | 0.46105 (18) | 0.31673 (14) | 0.0524 (6) | |
H3A | 0.3392 | 0.4105 | 0.3056 | 0.063* | |
H3B | 0.3382 | 0.5020 | 0.3550 | 0.063* | |
C4 | 0.38276 (19) | 0.5544 (2) | 0.19665 (15) | 0.0575 (7) | |
C5 | 0.4223 (3) | 0.6360 (2) | 0.22433 (19) | 0.0802 (9) | |
H5 | 0.3768 | 0.6747 | 0.2502 | 0.096* | |
C6 | 0.5282 (3) | 0.6629 (4) | 0.2151 (3) | 0.1131 (15) | |
H6 | 0.5549 | 0.7195 | 0.2352 | 0.136* | |
C7 | 0.5926 (3) | 0.6092 (5) | 0.1780 (3) | 0.1263 (19) | |
H7 | 0.6650 | 0.6277 | 0.1717 | 0.152* | |
C8 | 0.5551 (3) | 0.5289 (4) | 0.1493 (3) | 0.1313 (18) | |
H8 | 0.6011 | 0.4914 | 0.1227 | 0.158* | |
C9 | 0.4490 (3) | 0.5002 (3) | 0.1585 (2) | 0.0919 (11) | |
H9 | 0.4232 | 0.4434 | 0.1384 | 0.110* | |
C10 | 0.2057 (2) | 0.43200 (18) | 0.14431 (14) | 0.0510 (6) | |
C11 | 0.2171 (3) | 0.3432 (2) | 0.16084 (18) | 0.0748 (8) | |
H11 | 0.2500 | 0.3243 | 0.2145 | 0.090* | |
C12 | 0.1812 (4) | 0.2797 (3) | 0.1003 (2) | 0.0979 (11) | |
H12 | 0.1878 | 0.2181 | 0.1133 | 0.117* | |
C13 | 0.1377 (4) | 0.3056 (3) | 0.0240 (2) | 0.1121 (14) | |
H13 | 0.1158 | 0.2623 | −0.0177 | 0.135* | |
C14 | 0.1246 (5) | 0.3925 (3) | 0.0059 (2) | 0.1315 (18) | |
H14 | 0.0934 | 0.4105 | −0.0485 | 0.158* | |
C15 | 0.1567 (3) | 0.4562 (2) | 0.06664 (18) | 0.0946 (12) | |
H15 | 0.1445 | 0.5174 | 0.0539 | 0.113* | |
C16 | −0.0167 (2) | 0.63715 (19) | 0.39387 (15) | 0.0617 (7) | |
C17 | −0.1268 (3) | 0.6459 (2) | 0.3978 (2) | 0.0794 (9) | |
H17 | −0.1791 | 0.6080 | 0.3659 | 0.095* | |
C18 | −0.1622 (4) | 0.7116 (3) | 0.4495 (3) | 0.0995 (12) | |
H18 | −0.2384 | 0.7169 | 0.4534 | 0.119* | |
C19 | −0.0891 (5) | 0.7665 (3) | 0.4932 (2) | 0.1083 (14) | |
H19 | −0.1140 | 0.8108 | 0.5273 | 0.130* | |
C20 | 0.0181 (5) | 0.7596 (3) | 0.4891 (3) | 0.1299 (17) | |
H20 | 0.0694 | 0.7992 | 0.5198 | 0.156* | |
C21 | 0.0542 (3) | 0.6949 (3) | 0.4403 (2) | 0.1053 (13) | |
H21 | 0.1311 | 0.6900 | 0.4387 | 0.126* | |
C22 | −0.0661 (2) | 0.47956 (18) | 0.29188 (16) | 0.0570 (6) | |
C23 | −0.0948 (2) | 0.4642 (2) | 0.20833 (18) | 0.0760 (9) | |
H23 | −0.0593 | 0.4967 | 0.1702 | 0.091* | |
C24 | −0.1752 (3) | 0.4015 (3) | 0.1787 (3) | 0.0984 (11) | |
H24 | −0.1939 | 0.3913 | 0.1209 | 0.118* | |
C25 | −0.2265 (3) | 0.3553 (3) | 0.2329 (3) | 0.1001 (12) | |
H25 | −0.2825 | 0.3135 | 0.2129 | 0.120* | |
C26 | −0.1985 (3) | 0.3682 (2) | 0.3149 (3) | 0.0963 (12) | |
H26 | −0.2343 | 0.3347 | 0.3523 | 0.116* | |
C27 | −0.1184 (3) | 0.4293 (2) | 0.3456 (2) | 0.0806 (9) | |
H27 | −0.0990 | 0.4371 | 0.4037 | 0.097* | |
C28 | 0.1634 (2) | 0.69323 (19) | 0.11963 (15) | 0.0620 (7) | |
H28A | 0.2316 | 0.6663 | 0.1070 | 0.074* | |
H28B | 0.1767 | 0.7560 | 0.1341 | 0.074* | |
H28C | 0.1057 | 0.6888 | 0.0710 | 0.074* | |
C29 | −0.0101 (3) | 0.7237 (2) | 0.21083 (17) | 0.0710 (8) | |
H29A | −0.0825 | 0.6950 | 0.2074 | 0.085* | |
H29B | −0.0085 | 0.7599 | 0.1612 | 0.085* | |
H29C | 0.0029 | 0.7618 | 0.2601 | 0.085* | |
C31 | −0.0360 (5) | 0.0013 (6) | 0.0321 (3) | 0.088 (2) | 0.50 |
C32 | 0.0007 (9) | 0.0733 (6) | −0.0073 (6) | 0.073 (4) | 0.50 |
H32A | −0.0164 | 0.1326 | 0.0085 | 0.088* | 0.50 |
C33 | 0.0666 (6) | 0.0620 (5) | −0.0673 (5) | 0.097 (2) | 0.50 |
H33A | 0.0907 | 0.1117 | −0.0968 | 0.116* | 0.50 |
C34 | 0.1002 (14) | −0.0228 (7) | −0.0852 (10) | 0.136 (7) | 0.50 |
H34A | 0.1499 | −0.0330 | −0.1241 | 0.163* | 0.50 |
C35 | 0.0558 (7) | −0.0957 (5) | −0.0509 (7) | 0.119 (3) | 0.50 |
H35A | 0.0687 | −0.1554 | −0.0680 | 0.143* | 0.50 |
C36 | −0.0100 (14) | −0.0839 (7) | 0.0093 (10) | 0.122 (9) | 0.50 |
H36A | −0.0334 | −0.1332 | 0.0396 | 0.146* | 0.50 |
C37 | −0.0959 (12) | 0.0141 (9) | 0.1035 (8) | 0.133 (8) | 0.50 |
H37A | −0.1123 | −0.0457 | 0.1181 | 0.159* | 0.50 |
H37B | −0.0537 | 0.0431 | 0.1504 | 0.159* | 0.50 |
H37C | −0.1635 | 0.0461 | 0.0869 | 0.159* | 0.50 |
U11 | U22 | U33 | U12 | U13 | U23 | |
Pd1 | 0.04594 (11) | 0.03874 (13) | 0.03946 (10) | 0.00157 (7) | 0.00850 (7) | 0.00317 (7) |
P1 | 0.0540 (4) | 0.0504 (4) | 0.0442 (3) | 0.0069 (3) | 0.0171 (3) | 0.0049 (3) |
P2 | 0.0406 (3) | 0.0453 (4) | 0.0421 (3) | 0.0007 (2) | 0.0077 (2) | 0.0048 (2) |
C1 | 0.0715 (17) | 0.078 (2) | 0.0401 (12) | 0.0157 (14) | 0.0143 (11) | 0.0148 (12) |
C2 | 0.0648 (16) | 0.0618 (19) | 0.0498 (12) | 0.0147 (13) | 0.0148 (11) | 0.0192 (11) |
C3 | 0.0498 (13) | 0.0577 (18) | 0.0476 (12) | 0.0079 (11) | 0.0016 (10) | 0.0082 (11) |
C4 | 0.0441 (13) | 0.068 (2) | 0.0614 (14) | 0.0003 (13) | 0.0116 (11) | 0.0162 (12) |
C5 | 0.0681 (18) | 0.095 (3) | 0.0768 (18) | −0.0296 (17) | 0.0093 (15) | 0.0101 (16) |
C6 | 0.083 (3) | 0.143 (4) | 0.109 (3) | −0.055 (3) | 0.001 (2) | 0.037 (3) |
C7 | 0.059 (2) | 0.178 (5) | 0.143 (4) | −0.017 (3) | 0.017 (2) | 0.078 (4) |
C8 | 0.072 (3) | 0.157 (5) | 0.180 (4) | 0.031 (3) | 0.065 (3) | 0.052 (4) |
C9 | 0.0637 (19) | 0.093 (3) | 0.128 (3) | 0.0117 (17) | 0.0421 (19) | 0.018 (2) |
C10 | 0.0521 (14) | 0.0494 (18) | 0.0509 (12) | 0.0035 (11) | 0.0061 (10) | 0.0010 (10) |
C11 | 0.106 (2) | 0.054 (2) | 0.0647 (16) | 0.0010 (16) | 0.0146 (16) | 0.0015 (13) |
C12 | 0.149 (4) | 0.054 (2) | 0.093 (2) | −0.010 (2) | 0.026 (2) | −0.0113 (17) |
C13 | 0.159 (4) | 0.082 (3) | 0.088 (3) | −0.019 (3) | −0.001 (2) | −0.028 (2) |
C14 | 0.211 (5) | 0.091 (4) | 0.072 (2) | −0.001 (3) | −0.043 (3) | −0.007 (2) |
C15 | 0.145 (3) | 0.060 (2) | 0.0649 (17) | 0.009 (2) | −0.0245 (19) | −0.0052 (14) |
C16 | 0.0776 (18) | 0.061 (2) | 0.0527 (13) | 0.0111 (14) | 0.0303 (13) | 0.0058 (12) |
C17 | 0.082 (2) | 0.062 (2) | 0.105 (2) | 0.0143 (16) | 0.0464 (18) | 0.0121 (16) |
C18 | 0.110 (3) | 0.082 (3) | 0.124 (3) | 0.031 (2) | 0.075 (3) | 0.026 (2) |
C19 | 0.159 (4) | 0.092 (3) | 0.089 (2) | 0.026 (3) | 0.064 (3) | −0.005 (2) |
C20 | 0.148 (4) | 0.138 (4) | 0.107 (3) | 0.017 (3) | 0.028 (3) | −0.062 (3) |
C21 | 0.103 (3) | 0.120 (4) | 0.096 (2) | 0.010 (2) | 0.025 (2) | −0.049 (2) |
C22 | 0.0540 (14) | 0.0492 (18) | 0.0722 (16) | 0.0052 (12) | 0.0233 (12) | 0.0068 (12) |
C23 | 0.0651 (18) | 0.084 (2) | 0.0760 (18) | −0.0141 (16) | 0.0028 (14) | 0.0140 (15) |
C24 | 0.081 (2) | 0.099 (3) | 0.108 (3) | −0.024 (2) | −0.009 (2) | 0.007 (2) |
C25 | 0.065 (2) | 0.080 (3) | 0.157 (4) | −0.0120 (17) | 0.022 (2) | −0.001 (2) |
C26 | 0.097 (3) | 0.056 (2) | 0.153 (4) | −0.0095 (18) | 0.069 (3) | 0.007 (2) |
C27 | 0.100 (2) | 0.058 (2) | 0.095 (2) | −0.0030 (18) | 0.0515 (19) | 0.0064 (16) |
C28 | 0.0747 (17) | 0.0520 (18) | 0.0625 (15) | −0.0018 (13) | 0.0200 (13) | 0.0143 (12) |
C29 | 0.0845 (19) | 0.066 (2) | 0.0659 (16) | 0.0284 (16) | 0.0208 (14) | 0.0102 (13) |
C31 | 0.058 (4) | 0.134 (8) | 0.062 (4) | −0.024 (5) | −0.019 (3) | −0.004 (5) |
C32 | 0.063 (7) | 0.041 (6) | 0.104 (10) | −0.007 (5) | −0.023 (7) | −0.001 (6) |
C33 | 0.079 (5) | 0.098 (7) | 0.109 (6) | −0.014 (5) | 0.001 (4) | 0.027 (5) |
C34 | 0.109 (11) | 0.22 (2) | 0.071 (6) | 0.055 (11) | −0.005 (6) | −0.019 (8) |
C35 | 0.104 (7) | 0.076 (7) | 0.159 (9) | 0.020 (6) | −0.037 (7) | −0.023 (7) |
C36 | 0.113 (14) | 0.109 (15) | 0.134 (17) | −0.034 (11) | −0.015 (12) | 0.028 (12) |
C37 | 0.063 (7) | 0.21 (2) | 0.125 (12) | −0.040 (10) | 0.002 (7) | −0.012 (9) |
Pd1—C28 | 2.084 (2) | C13—C14 | 1.344 (6) |
Pd1—C29 | 2.087 (3) | C14—C15 | 1.390 (5) |
Pd1—P1 | 2.2999 (7) | C16—C17 | 1.367 (4) |
Pd1—P2 | 2.3038 (7) | C16—C21 | 1.371 (5) |
P1—C22 | 1.820 (3) | C17—C18 | 1.411 (5) |
P1—C16 | 1.821 (3) | C18—C19 | 1.339 (6) |
P1—C1 | 1.835 (2) | C19—C20 | 1.330 (7) |
P2—C10 | 1.820 (3) | C20—C21 | 1.374 (5) |
P2—C4 | 1.827 (2) | C22—C23 | 1.376 (4) |
P2—C3 | 1.828 (2) | C22—C27 | 1.388 (4) |
C1—C2 | 1.520 (4) | C23—C24 | 1.393 (5) |
C2—C3 | 1.524 (3) | C24—C25 | 1.356 (5) |
C4—C9 | 1.368 (4) | C25—C26 | 1.344 (6) |
C4—C5 | 1.368 (4) | C26—C27 | 1.381 (5) |
C5—C6 | 1.390 (5) | C31—C32 | 1.371 (7) |
C6—C7 | 1.340 (7) | C31—C36 | 1.384 (8) |
C7—C8 | 1.348 (7) | C31—C37 | 1.486 (7) |
C8—C9 | 1.401 (5) | C32—C33 | 1.375 (7) |
C10—C11 | 1.364 (4) | C33—C34 | 1.385 (8) |
C10—C15 | 1.366 (4) | C34—C35 | 1.380 (8) |
C11—C12 | 1.395 (5) | C35—C36 | 1.378 (8) |
C12—C13 | 1.335 (5) | ||
C28—Pd1—C29 | 85.05 (11) | C15—C10—P2 | 118.1 (2) |
C28—Pd1—P1 | 174.63 (8) | C10—C11—C12 | 121.1 (3) |
C29—Pd1—P1 | 89.72 (8) | C13—C12—C11 | 119.9 (4) |
C28—Pd1—P2 | 92.00 (8) | C12—C13—C14 | 120.4 (3) |
C29—Pd1—P2 | 176.49 (7) | C13—C14—C15 | 120.0 (3) |
P1—Pd1—P2 | 93.19 (3) | C10—C15—C14 | 121.0 (3) |
C22—P1—C16 | 105.84 (13) | C17—C16—C21 | 117.3 (3) |
C22—P1—C1 | 102.38 (14) | C17—C16—P1 | 125.1 (3) |
C16—P1—C1 | 101.59 (12) | C21—C16—P1 | 117.4 (2) |
C22—P1—Pd1 | 113.38 (8) | C16—C17—C18 | 119.6 (4) |
C16—P1—Pd1 | 114.97 (9) | C19—C18—C17 | 120.5 (4) |
C1—P1—Pd1 | 117.07 (9) | C20—C19—C18 | 120.6 (4) |
C10—P2—C4 | 103.91 (12) | C19—C20—C21 | 119.6 (5) |
C10—P2—C3 | 104.52 (12) | C16—C21—C20 | 122.4 (4) |
C4—P2—C3 | 99.22 (11) | C23—C22—C27 | 117.7 (3) |
C10—P2—Pd1 | 112.01 (8) | C23—C22—P1 | 118.6 (2) |
C4—P2—Pd1 | 118.38 (10) | C27—C22—P1 | 123.6 (2) |
C3—P2—Pd1 | 116.91 (8) | C22—C23—C24 | 121.0 (3) |
C2—C1—P1 | 113.24 (16) | C25—C24—C23 | 119.6 (4) |
C1—C2—C3 | 114.5 (2) | C26—C25—C24 | 120.3 (4) |
C2—C3—P2 | 116.32 (16) | C25—C26—C27 | 121.0 (3) |
C9—C4—C5 | 118.7 (3) | C26—C27—C22 | 120.3 (3) |
C9—C4—P2 | 122.9 (3) | C32—C31—C36 | 119.8 (6) |
C5—C4—P2 | 118.2 (2) | C32—C31—C37 | 120.4 (7) |
C4—C5—C6 | 120.9 (4) | C36—C31—C37 | 119.7 (7) |
C7—C6—C5 | 120.0 (5) | C31—C32—C33 | 120.7 (6) |
C6—C7—C8 | 120.2 (4) | C32—C33—C34 | 119.4 (7) |
C7—C8—C9 | 120.7 (5) | C35—C34—C33 | 119.7 (7) |
C4—C9—C8 | 119.5 (4) | C36—C35—C34 | 120.0 (7) |
C11—C10—C15 | 117.4 (3) | C35—C36—C31 | 119.7 (7) |
C11—C10—P2 | 124.49 (19) |
Experimental details
Crystal data | |
Chemical formula | [Pd(CH3)2(C27H26P2)]·0.5C7H8 |
Mr | 594.95 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 293 |
a, b, c (Å) | 12.260 (3), 15.025 (2), 16.347 (3) |
β (°) | 99.00 (2) |
V (Å3) | 2974.2 (10) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.75 |
Crystal size (mm) | 0.45 × 0.40 × 0.35 |
Data collection | |
Diffractometer | Stoe-IPDS image-plate diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 22466, 4521, 3825 |
Rint | 0.034 |
θmax (°) | 24.1 |
(sin θ/λ)max (Å−1) | 0.575 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.023, 0.062, 1.04 |
No. of reflections | 4521 |
No. of parameters | 355 |
No. of restraints | 55 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.28, −0.20 |
Computer programs: IDPS (Stoe & Cie, 1997)), IDPS, XMY93 (Debaermaeker, 1993), SHELXL97 (Sheldrick, 1997).
Pd1—C28 | 2.084 (2) | Pd1—P1 | 2.2999 (7) |
Pd1—C29 | 2.087 (3) | Pd1—P2 | 2.3038 (7) |
C28—Pd1—C29 | 85.05 (11) | C28—Pd1—P2 | 92.00 (8) |
C28—Pd1—P1 | 174.63 (8) | C29—Pd1—P2 | 176.49 (7) |
C29—Pd1—P1 | 89.72 (8) | P1—Pd1—P2 | 93.19 (3) |
The solvated dicationic palladium(II) complex [Pd(dppp)(NCCH3)2](BF4)2, bis(acetonitrile)[1,3-bis(diphenylphosphino)propane]palladium(II) bis(tetrafluoroborate), has been successfully used as catalyst precursor in the perfectly alternating copolymerization of alkenes with carbon monoxide (Abu-Surrah & Rieger, 1999). The two alternating propagation steps in this reaction are migratory insertion of carbon monoxide in the Pd–alkyl bond and subsequent migratory insertion of olefin in the resulting Pd–acyl bond. Since alkyl–palladium compounds with bidentate phosphines are of low stability, thermodynamically and kinetically, few of them have been structurally characterized (Wisner et al., 1986). Here we report on the X-ray structure of the dimethylpalladium complex [Pd(dppp)(CH3)2]·0.5C7H8, (I),
The bond lengths of the two Pd—CH3 distances [2.084 (2) and 2.087 (3) Å] are typical for Pd—C bonds (Crociani et al., 1980) and in close agreement with the values found in [Pd(dmpe)(CH3)2] [2.087 (4) Å; de Graaf et al., 1989; dmpe is 1,2-bis(dimethylphosphino)ethane], but they are significantly longer than those in [Pd(tmeda)(CH3)2] [2.026 (3) and 2.029 (3) Å; tmeda is N,N,N,,N,-tetramethylethylendiamine; de Graaf et al., 1989]; this is an indication to the larger trans influence of the diphosphine ligand (Abu-Surrah et al., 1999).
The lengths of the Pd—P bonds in the title compound (I) are 2.2999 (7) and 2.3038 (7) Å, which are longer than in the monomeric compound [Pd(dppp)Cl2] [Steffen & Palenik, 1976; 2.244 (2) and 2.249 (2) Å]. Phosphines trans to alkyl groups in square-planar complexes tend to have longer M—P bond distances because alkyl groups are believed to weaken the trans bond by inductive effect (Appleton et al., 1973; Saleem & Hodali, 1991).
The P—Pd—P angle of 93.19 (3)° in the dimethyl complex is significantly larger than that reported for the corresponding dichloride complex [89.32 (3)°], despite that both square-planar complexes contain the same diphosphine ligand. This indicate that the P—Pd—P angle is dependent not only on the ligand (Steffen & Palenik, 1976), but also on the influence of the alkyl groups occupying the two other coordinating positions. Upon formation of the Pd—C bond, believed to be the intermediate in catalytic processes forming C—C bonds, the steric constrains imposed by chelation of the dppp ligand decreases, thus leading to greater flexibility in the catalytically active palladium–alkyl species.