Indium Tris(bistriflylamide)-Catalyzed Addition of b-Keto Esters to 1,3-Diynes
FULL PAPERS
(spherical, neutral, 140–325 mesh). All 1H NMR spectra
(500 MHz) and 13C NMR spectra (125 MHz) were measured
on a JEOL ECA-500 for CDCl3 solutions in the presence of tet-
ramethylsilane as an internal standard and data are reported in
ppm (d). IR spectra were recorded on a React IR 1000 Reac-
tion Analysis System equipped with DuraSample IR (ASI Ap-
plied System) and are reported in cmÀ1. Anhydrous toluene
was distilled in the presence of CaH2 and stored over molecular
sieves in a storage flask. The water content of the solvent was
confirmed with a Karl-Fischer Moisture Titrator (MKC-210,
Kyoto Electronics Company) to be less than 10 ppm. The ab-
breviation rt stands for room temperature ranging from 15–
258C.
10 mol %) in degassed toluene (0.5 mL) was stirred at 258C
for 12 h. The resultant reaction mixture was filtered through
a pad of silica gel with ether as eluent to give a crude product.
Purification by silica gel column chromatography (2% EtOAc/
hexane) gave the title compound 16; yield: 240.4 mg (0.5 mmol,
1
100%); H NMR (500 MHz, CDCl3): d¼0.88 (t, J¼6.9 Hz,
3H), 1.30–1.36 (m, 4 H), 1.31 (t, J¼6.9 Hz, 3H), 1.37–1.56
(m, 2H), 1.73 (quint, J¼7.5 Hz, 2H), 1.79 (s, 3H), 2.17 (s,
3H), 2.93 (m, 2H), 4.28 (q, J¼6.9 Hz, 2H), 7.14 (aromatic, s,
1H), 7.18 (aromatic, s, 1H), 7.28 (aromatic, 5H), 7.39–7.41 (ar-
omatic, 1H), 7.44–7.47 (aromatic, 2H), 7.61–7.63 (aromatic,
2H); 13C NMR (125 MHz, CDCl3): d¼14.0, 21.2, 22.6, 27.2,
29.3, 30.7, 31.7, 35.5, 61.7, 64.6, 87.4, 96.6, 120.6, 123.5, 125.9,
126.8, 127.5, 127.7 (2C), 128.1, 128.2 (2C), 129.5 (2C), 131.1
(2C), 138.1, 140.8, 144.6, 145.9, 171.6, 204.5; IR: n¼2930 (m),
2856 (w), 1714 (s), 1598 (w), 1494 (m), 1459 (m), 1355 (m),
1243 (s), 1193 (m), 1092 (s), 1023 (m), 911 (w), 884 (w), 861
(w), 776 (m), 767 cmÀ1 (s); anal. calcd. for C33H36O3: C 82.46,
H 7.55, O 9.99; found: C 82.29, H 7.65.
Materials
Unless otherwise noted, materials were purchased from Tokyo
Kasei Co., Aldrich Inc., and other commercial suppliers and
were used after appropriate purification before use. In(OTf)3
was purchased from Aldrich Inc. and dried prior to use.
In(NTf2)3 and In(ONf)3 were prepared as described in the Sup-
porting Information and dried prior to use.
Acknowledgements
We thank the Ministry of Education, Culture, Sports, Science
and Technology of Japan for financial support, a Grant-in-
Aid for Specially Promoted Research, a Grant-in-Aid for
YoungScientists (A) (KAKENHI 1470311), and a Grant-in-
Aid for the 21st Century COE Program for Frontiers in Funda-
mental Chemistry.
Representative Procedure for Catalytic Addition of
Ethyl 2-Methyl-3-oxobutanoate (1) to 1,3-Decadiyne
(2a):
Ethyl 2-acetyl-2-methyl-3-methylene-4-undecynoate (3): In a
flame-dried reaction vessel, In(NTf2)3 was dried at 1408C un-
der reduced pressure (26 Pa) for 10 h. After the In-containing
vessel was flushed with argon at rt, a mixture of ethyl 2-methyl-
3-oxobutanoate (1; 151.4 mg, 1.05 mmol) and 1,3-decadiyne
(2a; 147.6 mg, 1.10 mmol, 1.05 equivs.), In(NTf2)3 (10.0 mg,
0.0105 mmol, 1 mol %) was heated at 608C in the dark for
48 h. The resulting reaction mixture was filtered through a
pad of silica gel with ether eluent to give a crude product. Pu-
rification by silica gel column chromatography (2% EtOAc/
hexane) gave the title compound 3; yield: 286.5 mg
References and Notes
[1] I. Kuwajima, E. Nakamura, Acc. Chem. Res. 1985, 18,
181–187.
[2] a) M. Palucki, S. L. Buchwald, J. Am. Chem. Soc. 1997,
119, 11108–11109; b) G. C. Lloyd-Jones, Angew. Chem.
Int. Ed. 2002, 41, 953–956; c) D. A. Culkin, J. F. Hartwig,
Acc. Chem. Res. 2003, 36, 234–245; d) T. Hama, X. Liu,
D. A. Culkin, J. F. Hartwig, J. Am. Chem. Soc. 2003, 125,
11176–11177; e) X. Liu, J. F. Hartwig, J. Am. Chem. Soc.
2004, 126, 5183–5191 and references cited therein.
[3] a) M. Nakamura, K. Endo, E. Nakamura, J. Am. Chem.
Soc. 2003, 125, 13002–13003; b) M. Nakamura, K. Endo,
E. Nakamura, Org. Lett. in press; zinc-mediated addition
of carbonyl to alkynes and alkenes, see also: c) M. Naka-
mura, T. Hatakeyama, E. Nakamura, J. Am. Chem. Soc.
2004, 126, 11820–11825; d) M. Nakamura, T. Fujimoto,
K. Endo, E. Nakamura, Org. Lett. 2004, 6, 4837–4840;
e) M. Nakamura, C. Liang, E. Nakamura, Org. Lett.
2004, 6, 2015–2017.
1
(1.03 mmol, 98%); H NMR (500 MHz, CDCl3): d¼0.889 (t,
J¼6.9 Hz, 3H), 1.24–1.32 (m, 4H), 1.28 (t, J¼6.9 Hz, 3H),
1.33–1.40 (m, 2H), 1.50 (quint, J¼6.9 Hz, 2H), 1.56 (s, 3H),
2.28 (t, J¼6.9 Hz, 2H), 2.32 (s, 3H), 4.23 (dq, J¼1.7, 6.9 Hz,
2H), 5.37 (s, 1H), 5.59 (s, 1H); 13C NMR (125 MHz, CDCl3):
d¼13.8, 13.9, 19.1, 19.9, 22.4, 27.3, 28.3, 28.4, 31.2, 61.4, 64.9,
78.6, 92.8, 122.3, 130.7, 170.8, 203.9; IR: n¼2934 (m), 2860
(m), 2223 (w), 1718 (s), 1606 (w), 1451 (m), 1355 (m),
1239 (s), 1112 (s), 1023 (m), 907 cmÀ1 (m); anal. calcd.
for C17H26O3: C 73.34, H 9.41, O 17.25; found: C 73.59,
H 9.60.
[4] S. Saito, Y. Yamamoto, Chem. Rev. 2000, 100, 2901–2915
and references cited therein.
[5] E. Nakamura, Y. Miyachi, N. Koga, K. Morokuma, J. Am.
Chem. Soc. 1992, 114, 6686–6692.
Representative Procedure for Palladium(0)-Catalyzed
[4þ2]Benzannulation; Reaction of Enyne (3) and 1,4-
Diphenyl-1,3-butadiyne (15a)
[6] C. G. Frost, J. P. Hartley, D. Griffin, Tetrahedron Lett.
2002, 43, 4789–4791.
[7] a) T. Tsuchimoto, T. Maeda, E. Shirakawa, Y. Kawakami,
Y. Chem. Commun. 2000, 1573–1574; b) T. Tsuchimoto,
K. Hatanaka, E. Shirakawa, Y. Kawakami, Chem. Com-
Ethyl
propanoate (16):
0.5 mmol), 1,4-diphenyl-1,3-butadiyne (15a; 121.4 mg,
0.6 mmol, 1.2 equivs.), Pd2dba3 ·CHCl3 (13.0 mg,
0.0125 mmol, 2.5 mol %), and P(o-tol)3 (15.2 mg, 0.05 mmol,
2-acetyl-2-(3’-hexyl-4’-phenylethynyl-5’-biphenyl)-
A
mixture of enyne (3; 139.2 mg,
Adv. Synth. Catal. 2005, 347, 1681 – 1686
ꢁ 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
1685