2
242
Synlett
F. Louafi et al.
Letter
(
(
(
(
14) Under conditions of method B, but in the absence of a Pd(II) cat-
(27) For recent examples of oxypalladation followed by carbopalla-
dation–β-hydride elimination, see: (a) Tietze, L.; Stecker, F.;
Zinngrebe, J.; Sommer, K. M. Chem. Eur. J. 2006, 12, 8770.
(b) Tietze, L.; Sommer, K. M.; Zinngrebe, J.; Stecker, F. Angew.
Chem. Int. Ed. 2005, 44, 257.
alyst, this same oxidative lactonization gave the desired com-
pounds in very low yields (less than 10% after 48 h).
15) For the conversion of 1a into 3a in AcOH in the presence of
PhI(OAc) and catalytic TfOH, see: Kang, Y.-B.; Gade, L. H. J. Am.
2
Chem. Soc. 2011, 133, 3658.
(28) For a definition of domino sequences in a catalytic transforma-
tion, see: (a) Poli, G.; Giambastiani, G. J. Org. Chem. 2002, 67,
9456. (b) Prestat, G.; Poli, G. Chemtracts Org. Chem. 2004, 17, 97.
16) The protocol in AcOH was not optimized. However, this result is
consistent with a protocatalytic nature of alkene diacetoxyl-
1
ation in the presence of PhI(OAc) ; see ref. 14.
(29) Given the complexity of the crude H NMR spectrum, we were
2
17) (a) Gormisky, P. E.; White, M. C. J. Am. Chem. Soc. 2011, 133,
not able to determinate the diastereomeric ratios for com-
pounds 5 and 6. Although we did not optimize this domino
sequence, the results still confirm our conclusions concerning
the involvement of the cyclic OxPI intermediate.
12584. (b) Chen, M. S.; Prabagaran, N.; Labenz, N. A.; White, M.
C. J. Am. Chem. Soc. 2005, 127, 6970. (c) Fraunhoffer, K. J.;
Prabagaran, N.; Sirois, L. E.; White, M. C. J. Am. Chem. Soc. 2006,
1
28, 9032. (d) Ammann, S. E.; Rice, G. T.; White, M. C. J. Am.
(30) (a) General Procedures; Conditions A: In a sealed tube, under
an argon atmosphere, were added the carboxylic acid (1.0
equiv), Pd(OAc)2 (0.1 equiv), bis-sulfoxide ligand (0.15 equiv),
Chem. Soc. 2014, 136, 10834.
(
18) According to the present knowledge on this domain, the Pd(II)-
to-Pd(IV) oxidation might take place prior to or after (ref. 6b)
the oxypalladation step. See: (a) Pilarski, L. T.; Selander, N.;
Böse, D.; Szabó, K. J. Org. Lett. 2009, 11, 5518. (b) Alam, R.;
Pilarski, L. T.; Pershagen, E.; Szabó, K. J. J. Am. Chem. Soc. 2012,
p-phenylbenzoquinone (1.07 equiv), NaOAc (1.0 equiv) and CH Cl2
2
(0.5 M). The tube was sealed and the reaction was allowed to
stir at 45 °C. After 24 h, the reaction mixture was filtered on a
plug of celite. The filtrate was treated with a sat. aq solution of
5% K CO and the aqueous layer was extracted with CH Cl (3 ×).
134, 8778. (c) Check, C. T.; Henderson, W. H.; Wray, B. C.; Eyden,
2
3
2
2
M. J. V.; Stambuli, J. P. J. Am. Chem. Soc. 2011, 133, 18503.
19) Powers, D. C.; Ritter, T. Nat. Chem. 2009, 1, 302.
20) For a recent example of Pd(II)-catalyzed intramolecular acylox-
The combined organic layers were dried over anhyd MgSO , fil-
tered and concentrated under reduced pressure. Purification by
flash silica gel column chromatography afforded the desired
4
(
(
ylation–acetoxylation in the presence of PhI(OAc) , see: Li, Y.;
vinyl lactone. Analytical Data for 2b: Yield: 59%; colorless oil.
2
1
Song, D.; Dong, V. M. J. Am. Chem. Soc. 2008, 130, 2962.
21) For recent examples of intramolecular oxypalladation followed
by β-hydride elimination, see: (a) Takenaka, K.; Akita, M.;
Tanigaki, Y.; Takizawa, S.; Sasai, H. Org. Lett. 2011, 13, 3506.
H NMR (300 MHz, CDCl ): δ = 5.86 (ddd, J = 17.1, 10.5, 6.0 Hz,
3
(
1 H), 5.33 (dt, J = 17.2, 1.2 Hz, 1 H), 5.22 (dt, J = 10.5, 1.1 Hz, 1 H),
4.87–4.95 (m, 1 H), 2.50 (ddd, J = 8.0, 6.9, 1.1 Hz, 2 H), 2.31–2.46
(m, 1 H), 1.87–2.07 (m, 1 H). These data are in good agreement
with those reported in the literature (ref. 11). Conditions B: In a
sealed tube, under an argon atmosphere, were added the car-
boxylic acid (1.0 equiv), Pd(OAc)2 (0.1 equiv), bis-sulfoxide
ligand (0.15 equiv), iodobenzene diacetate (2.1 equiv), NaOAc
(1.0 equiv) and CH Cl (0.5 M). The tube was sealed and the
(b) Trend, R. M.; Ramtohul, Y. K.; Stoltz, B. M. J. Am. Chem. Soc.
2005, 127, 17778. (c) Hayashi, T.; Yamasaki, K.; Mimura, M.;
Uozumi, Y. J. Am. Chem. Soc. 2004, 126, 3036.
(
22) For a similar by-product obtained after a Mizoroki–Heck cou-
pling between in situ generated PhI and alkene, see: (a) Ref 4a.
2
2
(
1
b) Qu, X.; Sun, P.; Li, T.; Mao, J. Adv. Synth. Catal. 2011, 353,
061. (c) Evdokimov, N. M.; Kornienko, A.; Magedov, I. V. Tetra-
reaction was allowed to stir at 45 °C for 24 h. The mixture was
filtered over a small pad of celite. The filtrate was treated with a
sat. aq solution of 5% K CO and the aqueous layer was extracted
hedron Lett. 2011, 52, 4327.
2
3
(
23) We assume that the Mizoroki–Heck process generates the
iodide anion required for the iodolactonization. See: Liu, H.; Tan,
C-. H. Tetrahedron Lett. 2007, 48, 8220.
with CH Cl (3 ×). The combined organic layers were dried over
2 2
anhyd MgSO , filtered and concentrated under reduced pres-
4
sure. Purification by flash silica gel column chromatography
(
(
(
24) McDonald, R. I.; Liu, G.; Stahl, S. S. Chem. Rev. 2011, 111, 2981.
25) Lyons, T. W.; Sanford, M. S. Chem. Rev. 2010, 110, 1147.
26) The trans configuration (erythro) of 3e and the cis configuration
afforded the acetoxylated product. Analytical Data for 3b:
1
yield: 41%; yellow oil. H NMR (300 MHz, CDCl ): δ = 4.45–4.53
3
(m, 1 H), 4.18 (dd, J = 12.0, 3.8 Hz, 1 H), 4.12 (dd, J = 12.0, 5.8 Hz,
1 H), 2.30–2.74 (m, 2 H), 2.04 (s, 3 H), 1.70–2.00 (m, 3 H), 1.50–
1.71 (m, 1 H). (b) These data are in good agreement with those
reported in the literature: Ha, H. J.; Park, Y. S.; Park, G. S.
ARKIVOC 2001, (i), 55.
(
threo) of 3e′ were clearly attributed with the J , coupling con-
3 4
1
stants in the H NMR spectra, and compared with the data
reported in the literature, see: (a) Pakuiski, Z.; Zamojski, A. Tet-
rahedron 1995, 51, 871. (b) Tiecco, M.; Testaferri, L.; Tingoli, M.;
Bartoli, D. Tetrahedron 1990, 46, 7139.
©
Georg Thieme Verlag Stuttgart · New York — Synlett 2015, 26, 2237–2242