COMMUNICATIONS
Palladium-Catalyzed Decarbonylative Dehydration of Fatty Acids
[a]
Conditions: 20 mmol 1, 6 portions of Ac O, 1 +0.14+0.12+0.10+0.09+0.08 equiv.,
2
added every 30 min.
[
[
[
[
[
b]
c]
d]
e]
f]
Isolated yield (column chromatography).
1
Determined by H NMR.
Purified by distillation.
18.5 mmol 1e.
PdCl (nbd) (0.05 mol%), PPh (0.05 mol%), Xantphos (0.06 mol%), 1.5 h, 3 portions of
AHCTUNGTRENNUNG
2
3
Ac O (1+0.15+0.10 equiv.).
Single isomer observed.
2
[
[
g]
h]
PdCl ACHTNUGTRENN(NGU PPh ) (0.25 mol%), Xantphos (0.30 mol%), (t-Bu) biphenol (1 mol%), 2n:3n=
2
3
2
4
4
2
9:51.
-Methyldecanoic anhydride (10 mmol), no Ac O, PdCl AHCTUNTGERNNUNG( nbd) (1 mol%), Xantphos
2
[i]
2
(
1.1 mol%), salicylamide (2 mol%), 1608C, 10 mmHg distillation, 10 h, 3p:2p=73:27.
Table 4. Synthesis of pheromones 4a and 4b from olefin 2f.
tech Center for Catalysis and Chemical Synthesis, and Cal-
tech for financial support. Materia, Inc. is thanked for the
generous donation of ruthenium catalysts. Dr. David Vander-
Velde is acknowledged for NMR spectroscopy assistance. Dr.
Mona Shahgholi and Naseem Torian are acknowledged for
high-resolution mass spectrometry assistance. Dr. Scott Virgil
is acknowledged for helpful discussions.
References
[
1] S. D. Ittel, L. K. Johnson, M. Brookhart, Chem. Rev.
000, 100, 1169–1203.
2
[
2] a) D. M. Marquis, S. H. Sharman, R. House, W. A.
Sweeney, J. Am. Oil Chem. Soc. 1966, 43, 607–614;
b) R. Franke, D. Selent, A. Bçrner, Chem. Rev. 2012,
1
12, 5675–5732.
[
3] a) A. M. Al-Jarallah, J. A. Anabtawi, M. A. B. Siddiqui,
[
[
a]
b]
4
.8 mmol 2f.
A. M. Aitani, A. W. Al-Sa’doun, Catal. Today 1992, 14,
1
Determined by H NMR.
1
–121; b) B. L. Small, M. Brookhart, J. Am. Chem. Soc.
1
998, 120, 7143–7144.
a vacuum of 1–5 mmHg. Acetic anhydride was added as fol-
lows (0.12, 0.10, 0.09, 0.08 equiv.) in the same manner every
[4] J. Ouyang, F. Kong, G. Su, Y. Hu, Q. Song, Catal. Lett.
2009, 132, 64–74.
[5] Prices of acids and olefins (Sigma–Aldrich, 10/5/2013):
30 min. The reaction was stopped at t=3 h and allowed to
cool to ambient temperature. The residual reaction mixture
was purified by flash chromatography. If it contained solids,
it was suction-filtered first and the solids washed with hex-
anes, and the filtrate was concentrated and purified by chro-
matography. In cases where the product was distilled togeth-
er with acetic acid, the distillate was added dropwise to a sa-
turated NaHCO solution, stirred for 30 min, and the result-
3
ing mixture was extracted with dichloromethane (30 mLꢂ
3
). The combined extracts were dried over Na SO , filtered
2 4
and concentrated. The crude product was then subjected to
flash chromatography or distillation to afford the olefin in
pure form.
[
6] a) M. B. Herbert, V. M. Marx, R. L. Pederson, R. H.
Grubbs, Angew. Chem. 2013, 125, 328–332; Angew.
Chem. Int. Ed. 2013, 52, 310–314; b) L. E. Rosebrugh,
M. B. Herbert, V. M. Marx, B. K. Keitz, R. H. Grubbs,
J. Am. Chem. Soc. 2013, 135, 1276–1279.
Acknowledgements
The authors wish to thank the Resnick Sustainability Institute
at Caltech (graduate fellowship to Y.L.), BP (postdoctoral
fellowship to A.F. under the XC2 program), NIH-NIGMS
[
7] J. D. Bacha, J. K. Kochi, Tetrahedron 1968, 24, 2215–
(
R01GM080269, B.M.S.), NIH (NIH 5R01GM031332-27,
2
226.
R.H.G.), the Gordon and Betty Moore Foundation, the Cal-
Adv. Synth. Catal. 2014, 356, 130 – 136
ꢁ 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
135