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ChemComm
DOI: 10.1039/C5CC03479E
COMMUNICATION
Journal Name
2
014, 16, 1072; (
j
) L. Wang, C. Xu, L. Chen, X. Hao and D. Z.
OTBDPS
OTBDPS
H
Wang, Org. Lett., 2014, 16, 1076; (k) X. Xiong, Y. Li, Z. Lu, M.
H
1
) HCO H
Wan, J. Deng, S. Wu, H. Sha and A. Li, Chem. Commun., 2014, 50,
2
TBSO
B
TBSO
Et O, rt, 74%
2
5294.
C
2
) Dess–Martin
periodinane
8
9
Selected reviews of Sm-mediated transformations:
Molander and C. R. Harris, Chem. Rev. 1996, 96, 307; (
Edmonds, D. Johnston and D. J. Procter, Chem. Rev. 2004, 104
371; ( ) K. C. Nicolaou, S. P. Ellery and J. S. Chen, Angew. Chem.,
Int. Ed., 2009, 48, 7140.
(a)
G. A.
H
H
TrO
MeO C
O
D
b
) D. J.
CH Cl , rt, 83%
2
2
MeO C
2
2
,
23
26
3
c
OTBDPS
OTBDPS
(
(
a
b
) E. D. Mihelich and D. J. Eickhoff, J. Org. Chem., 1983, 48, 4135;
) T. G. Waddell, A. D. Carter and T. J. Miller, J. Org. Chem., 1992,
SmI
LiCl
2
H
H
TBSO
TBSO
RO
t-BuOH
+
57, 381.
A
THF, 0 °C
4
4
H
H
10 M. Shibuya, M. Tomizawa, I. Suzuki and Y. Iwabuchi, J. Am. Chem.
Soc., 2006, 128, 8412.
O
MeO C
2
H
2
H
1
1
Taura, M. Tanaka, X.-M. Wu, K. Funakoshi and K. Sakai,
O
2
7
1%
Ac O, pyr., rt
28 (R = H) <58%
Tetrahedron, 1991, 47, 4879.
2
31% in 2 steps
2
9 (R = Ac)
12 (
(
a
b
) D. Milstein and J. K. Stille, J. Am. Chem. Soc., 1978, 100, 3636;
) J. K. Stille, Angew. Chem., Int. Ed., 1986, 25, 508.
1
3 We could not get the fully substituted enol triflate even under
CO
2
Me
CO Me
2
H
H
thermodynamic conditions. Preliminary calculation of simpler model
bicyclic enol triflate suggested that the less-substituted enol triflate in
16 is more stable than the fully substituted one. In the tricyclic [7–5–
B
OAc
HO
HO
HO
A
C
4
4
N
H
D
N
H
AcO
5] system, the tetrasubstituted olefin in 4 is suggested to be less stable
than the trisubstituted olefin. However, the energy difference is
smaller than in the bicyclic system. We would have a chance of
isomerization into the desired isomer after construction of [7–5–5] or
yuzurimine (1)
yunnadaphnine C (30)
Scheme 5 Synthesis of the [6–7–5–5] tetracarbocyclic core of yuzurimine-type
alkaloids
[
6–7–5–5] carbocyclic skeleton. Currently, we are examining the
isomerization of the double bond from the C10–C17 to the C9–C10
for the synthesis of yuzururimine-type alkaloids.
1
4 (
Prod., 2006, 69, 553; (
Wu and X. J. Hao, J. Nat. Prod., 2006, 69, 1074.
a
) H. Zhang, S. P. Yang, C. Q. Fan, J. Ding and J. M. Yue, J. Nat.
b
) Y. T. Di, H. P. He, Y. L. Ping, Y. L. Li, L.
Notes and references
1
2
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15 Y. Yoshida, K. Shimonishi, Y. Sakakura, S. Okada, N. Aso and Y.
(
a
7
,
Tanabe, Synthesis, 1999, 1633.
6
b
) H. Sakurai, H. Irikawa, S. Yamamura and Y. Hirata, 16 In our unpublished result, elongation reaction of a similar aldehyde to
, 2883; ( ) S. Yamamura, H. Irikawa, Y.
an -unsaturated ester was only proceeded by using phosphorane
21; C. Harcken and S. F. Martin, Org. Lett., 2001, , 3591.
8
c
α,β
3
3
4
5
5
17 The structure of seven-membered enone 23 was determined by
J. Kobayashi, S. Ueno and H. Morita, J. Org. Chem., 2002, 67, 6546.
M. E. Weiss and E. M. Carreira, Angew. Chem., Int. Ed., 2011, 50
analysis of 2D NMR spectra (see the Supporting Information).
,
,
18 Selected examples of SmCl
Link and L. E. Overman, J. Am. Chem. Soc., 1996, 118, 8166; (
M. Ready, S. E. Reisman, M. Hirata, M. M. Weiss, K. Tamaki, T. V.
Ovaska and J. L. Wood, Angew. Chem., Int. Ed., 2004, 43, 1270; (
2
mediated reductive couplings: (
a
) J. T.
1
1501.
b
) J.
6
7
(a
) A. Shvartsbart and A. B. Smith, III, J. Am. Chem. Soc., 2014, 136
8
70; (
b
) A. Shvartsbart and A. B. Smith, III, J. Am. Chem. Soc., 2015,
c)
1
37, 3510.
J. Y. Cha, J. T. S. Yeoman and S. E. Reisman, J. Am. Chem. Soc.
2011, 133, 14964.
,
Review: B. Kang, P. Jakubec and D. J. Dixon, Nat. Prod. Rep., 2014,
, 550; Synthetic study of yuzurimine-type alkaloids: (
Urbaneja and J. Bonjoch, Org. Lett., 2005, , 5461; (
A. J. M. Burrell, H. D. S. Guerrand and N. Oram, Org. Lett., 2011, 20 The structures of lactone 27 and tetracyclic compound 28 were
3
1
a) D. Solé, X. 19 Tetracyclic compound 28 contains a small amount of impurities. The
7
b
) I. Coldham,
yield of 29 was calculated from 26
.
1
3
, 1267; (
and D. Z. Wang, Org. Lett., 2011, 13, 1812; (
Boudreault and F. Lévesque, Org. Lett., 2011, 13, 6204; (
Coldham, L. Watson, H. Adams and N. G. Martin, J. Org. Chem.
011, 76, 2360; ( ) B. Darses, I. N. Michaelides, F. Sladojevich, J. W.
Ward, P. R. Rzepa and D. J. Dixon, Org. Lett., 2012, 14, 1684; ( ) Y.
Yao and G. Liang, Org. Lett., 2012, 14, 5499; ( ) C. Xu, L. Wang, X.
Hao and D. Z. Wang, J. Org. Chem., 2012, 77, 6307; ( ) A. A.
c
) C. Xu, Z. Liu, H. Wang, B. Zhang, Z. Xiang, X. Hao
) G. Bélanger, J.
) I.
determined by analysis of 2D NMR spectra. The stereochemistry of
tetracyclic compound 28 was established by NOESY correlations of
acetate 29 (see the Supporting Information).
d
e
,
21 Y.-T. Di, H.-P. He, C.-S. Li, J.-M. Tian, S.-Z. Mu, S.-L. Li, S. Gao
and X.-J. Hao, J. Nat. Prod., 2006, 69, 1745.
2
f
g
h
i
Ibrahim, A. N. Golonka, A. M. Lopez and J. L. Stockdill, Org. Lett.
,
4
| J. Name., 2012, 00, 1-3
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