Organometallics
Article
Pd(lutidine)} (8b; 50 mg, 61 μmol, 1 equiv) in benzene (1.8 mL).
Allyl acetate (165 mg, 1.65 mmol, 27 equiv) was added, and the
mixture was stored overnight at ambient temperature. The vial was
then placed in a 20 mL glass vial containing n-hexane, which was
sealed. Within 40 h yellow crystals formed, which were isolated and
washed with n-pentane (39 mg, 47 μmol, 78%). Mp: 128−138 °C dec.
1H NMR (400.3 MHz, benzene-d6): δ 1.64 (s, 3H, CH3), 3.1−3.22
(m, 2H, Hallyl), 3.48−3.57 (m, 2H, Hallyl), 4.75−4.90 (m, 1H, Hallyl),
6.48−6.53 (m, 2H), 6.48−6.61 (m, 2H), 6.87−6.96 (m, 7H), 6.97−
7.03 (m, 9H), 7.24−7.30 (m, 1H), 7.30−7.39 (m, 3H), 7.45−7.68 (br,
5H), 7.70−7.74 (m, 2H), 8.06−8.10 (m, 2H). 1H NMR (400.3 MHz,
THF-d8): δ 1.24 (s, 3H, CH3), 3.35- 3.45 (m, 4H, Hallyl), 5.57−5.69
(m, 1H, Hallyl), 6.26−6.34 (m, 2H), 6.46−6.53 (m, 2H), 6.88−6.94
(m, 1H), 6.95−7.01 (m, 5H), 7.03−7.12 (m, 5H), 7.12−7.22 (m,
11H), 7.40−7.48 (m, 5H), 7.54−7.57 (m, 2H). 11B{1H} NMR (128.4
MHz, benzene-d6): δ 3.3 (s, w1/2 = 67 Hz). 13C{1H} NMR (100.6
MHz, benzene-d6) = δ 25.2 (s, OAc), 73.1 (s), 116.4 (s, Callyl). 31P
After the indicated heating period the NMR tubes were cooled in an
ice bath for approximately 10 s. Complete cooling was demonstrated
by solidification of benzene-d6. H NMR spectra were recorded after
1
thawing of the sample.
ASSOCIATED CONTENT
* Supporting Information
■
S
Text, figures, and CIF and XYZ files giving full experimental
details, selected NMR spectra, Cartesian coordinates for
optimized structure 8a, and crystallographic data for CCDC
1049711 (8a), CCDC 1031952 (9a), and CCDC 1054024
(9b). The Supporting Information is available free of charge on
AUTHOR INFORMATION
Corresponding Author
31
NMR (162.0 MHz, benzene-d6): δ 20.22 (s). P{1H} NMR (162.0
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MHz, THF-d8): δ 19.38 (s). IR (KBr): ν
̃
/cm−1 3090 (vw, sh), 3060
(w, sh), 3035 (m), 1957 (vw), 1813 (vw), 1690 (w, sh), 1652 (m),
1582 (w, sh), 1478 (m), 1447 (w), 1364 (m), 1288 (m), 1190 (w),
1182 (m), 1131 (m), 1093 (m), 1070 (w, sh), 1026 (m), 1001 (m),
938 (m), 851 (m), 821 (m), 728 (m), 746 (s), 696 (s), 678 (vs), 640
(m), 638 (m), 616 (m), 537 (m), 526 (m, sh), 510 (m, sh), 492 (m).
Anal. Calc. for C56H50BO2P2Pd: C, 72.00; H, 5.39. Found C, 71.35; H,
5.24.
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
This work is dedicated to Prof. Dr. Peter Hofmann (University
of Heidelberg) in recognition of his support and advice as
“Doktorvater” of MET. We thank the Excellence Initiative of
the German federal and state governments for financial support,
the Chemical Industry Fund for a Liebig fellowship to M.E.T,
Synthesis of {[(o-PPh2C6H4)2B(OBz)Ph]Pd(η3-C3H5)} (9b).
Complex 8b (22 mg, 0.026 mmol, 1 equiv) and allyl benzoate (15
mg, 0.094 mmol, 3.6 equiv) were weighed into a glass vial. Benzene
(0.7 mL) was added, and the mixture was stirred for 10 min. The
solution was then transferred into a Wilmad quick pressure valve NMR
tube and immediately overlaid with hexane (0.4 mL). Within 24 h
single crystals suitable for X-ray analysis were formed. 1H NMR (400.1
MHz, THF-d8): δ 2.23 (br s, 2H, CH2), 3.40−3.30 (m, 2H, CH2),
5.54−5.43 (m, 1H, CH). 11B{1H} NMR (128.4 MHz, THF-d8): δ 4.5
(w1/2 = 220 50 Hz). 31P{1H} NMR (161.9 MHz, THF-d8): δ 17.6
(s, w1/2 = 180 Hz).
the Hans-Bockler-Stiftung for a fellowship to T.S., and the
̈
Alexander von Humboldt Foundation for a fellowship to L.M.
We are grateful to Dr. F. Pan and Dr. C. Merkens for collection
of X-ray diffraction data and to Dr. T. P. Spaniol for help with
structure refinement. The authors thank Prof. Dr. J. Okuda for
generous support and helpful discussions and Prof. Dr. P.
Hayes for valuable input.
{[(o-PPh2C6H4)2B(O2CCF3)Ph]Pd(η3-C3H5)} (9c; NMR Experi-
ment). In a glovebox a glass vial was charged with complex 8b (10 mg,
13 μmol, 1 equiv) and neat allyl trifluoroacetate (7.5 mg, 49 μmol, 4
equiv). THF-d8 (0.7 mL) was added quickly, and the yellow solution
was transferred to a Wilmad quick pressure NMR tube. NMR analysis
was performed within 1 h. 1H NMR (400.3 MHz, THF-d8): δ 2.12 (bs,
2H, CH2), 3.58 (bs, 2 H, CH2), 5.54 (bs, 1H, CH). 11B{1H} NMR
(128.4 MHz, THF-d8): δ 4.5 (w1/2 = 350 Hz). HSQC (400.3 MHz,
THF-d8): δ 2.12/75.08, 3.58/75.08, 5.54/118.00. 31P{1H} NMR
(162.0 MHz, THF-d8): 19.3 (s, w1/2 = 11 Hz).
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of complex 8b (20 mg, 7.0 μmol) in benzene-d6 (1.00 mL) was
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progress was monitored by H NMR spectroscopy. In the case of
complex 9a the NMR tube was heated within the NMR machine to 60
°C. NMR tubes containing catalyst 8a or 8b were heated in a
thermostated water bath (60.0 °C, Lauda ECO Silver thermostat).
1983
Organometallics 2015, 34, 1978−1984