(ddd, J = 7.5, 7.5, 15.5 Hz, 1H), 6.37 (d, J = 16.0 Hz, 1H), 6.88 (d, J =
9.0 Hz, 2H), 7.19–7.35 ppm (m, 12H); 13C NMR (125 MHz): d = 42.6,
46.1, 55.56, 55.59, 74.5, 114.2, 123.4, 126.8, 127.5, 128.5, 130.4, 131.1,
133.6, 137.5, 159.2 ppm. FT-IR (CH2Cl2): 3559, 3028, 2919, 2836, 2361,
2343, 1607, 1511, 1495, 1454, 1298, 1248, 1175, 1113, 1086, 1033, 970,
888, 834, 753, 725, 702 cmÀ1. HRMS calcd for C25H27O2 [M+H]+
359.2006, found 359.2000.
General procedure for the oxyarylation of olefins: Homoallylic
alcohol 1a (25.2 mg, 0.1 mmol), boronic acid 2a (18.2 mg, 0.12 mmol),
benzoquinone (11 mg, 0.1 mmol), Pd(TFA)2 (3.3 mg, 0.01 mmol) and
4,4’-di-tert-butyl-2,2’-bipyridyl (3.2 mg, 0.012 mmol) were loaded into
a dry vial, which was subjected to evacuation/flushing with dry argon
three times. Anhydrous dichloroethane (0.8 mL) followed by tri-
fluoroacetic acid (1.5 mL, 0.02 mmol) were syringed into the mixture,
which was then stirred at 608C for 40 h or until the starting material
had been consumed, as determined by TLC. Upon cooling to room
temperature, all volatiles were evaporated and the residue was
purified by preparative TLC (eluent: ethyl acetate/hexane 1:6) to give
6a as pale yellow oil in 75% yield. 1H NMR (400 MHz): d = 1.37–1.43
(m, 1H), 1.85–1.90 (m, 1H), 1.90–2.01 (m, 2H), 2.86 (d, 2.93, J =
13.6 Hz, 1H), 2.92 (d, J = 13.6 Hz, 1H), 2.99 (d, J = 13.2 Hz, 1H), 3.01
(d, J = 13.6 Hz, 1H), 3.80 (s, 3H), 4.47 (dd, J = 5.2, 9.6 Hz, 1H), 6.84
(d, J = 8.4 Hz, 2H), 7.13 (d, J = 8.8 Hz, 2H), 7.23–7.34 ppm (m, 10H);
13C NMR (100 MHz): d = 33.5, 34.6, 46.1, 47.1, 55.5, 81.1, 85.7, 113.8,
126.4, 126.5, 128.0, 128.1, 128.2, 131.2, 131.3, 134.6, 138.3, 138.4,
159.2 ppm. FT-IR (CH2Cl2) 3060, 3027, 2936, 2835, 1613, 1513, 1494,
[4] For the functionalization of olefins by C H bond activation, see:
[5] For another strategy to construct tetrahydrofuran by palla-
À
dium(0)-mediated olefin insertion into a Pd O bond, see: a) J. P.
[6] For examples of oxidative Heck reactions involving chelating
S. Li, W. Jia, J. Xiao, Q. Liu, L. Zhang, N. Jiao, Angew. Chem.
[7] Excess TFA dehydrated the starting material resulting in
diminished yields.
1454, 1302, 1246, 1173, 1082, 1035, 942, 827, 754, 736, 701 cmÀ1
.
HRMS calcd for C25H27O2 [M+H]+ 359.2006, found 359.2016.
Received: March 16, 2011
Revised: April 30, 2011
Published online: June 8, 2011
[8] For details, see the Supporting Information.
Keywords: cyclization · homogeneous catalysis ·
olefin functionalization · oxyarylation · palladium
[9] The relative configuration was determined by 1H NMR, see:
a) G. Dana, E. Touboul, O. Convert, Y. L. Pascal, Tetrahedron
.
[1] For reviews, see: a) C. Jia, T. Kitamura, Y. Fujiwara, Acc. Chem.
[2] For reviews, see: a) R. F. Heck, Comprehensive Organic Syn-
thesis, Vol. 4 (Ed.: B. M. Trost), Pergamon, New York, 1991,
c) G. T. Crisp, Chem. Soc. Rev. 1998, 27, 427; d) N. J. Whitcombe,
g) B. Karimi, H. Behzadnia, D. Elhamifar, P. F. Akhavan, F. K.
À
[10] Because of the higher dissociation energy of a C D bond than a
À
C H bond, the b-hydride elimination becomes the competitive
reaction to the b-deuteride elimination, thus resulting in the
retention of 36% deuterium at a-carbon atom.
[11] For examples, see: a) M. M. Konnick, B. A. Gandhi, I. A. Guzei,
[12] For examples, see: a) M. S. Chen, N. Prabagaran, N. A. Labenz,
[3] Other examples involving the trapping of a s-alkyl palladium(II)
Heck intermediate, see: a) K. C. Nicolaou, D. J. Edmonds, P. G.
Angew. Chem. Int. Ed. 2011, 50, 6626 –6629
ꢀ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim