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DOI: 10.1055/s-0030-1259677
Synthetic Studies toward the Total Synthesis of Chlorahololide A
Publication History
Publication Date:
22 February 2011 (online)
Abstract
The highly stereoselective synthesis of core framework 4, a pivotal intermediate for the total synthesis of chlorahololide A, is reported. The approach features t-BuCu-mediated stereoselective reduction of α,β-unsaturated diketone 8, Wharton transposition, Simmons-Smith cyclopropanation and cascade enol lactonization.
Key words
chlorahololide A - Hajos-Parrish ketone - Wharton transposition - cyclopropanation - enol lactonization
- Supporting Information for this article is available online:
- Supporting Information
- 1
Yang SP.Gao ZB.Wang FD.Liao SG.Chen HD.Zhang CR.Hu GY.Yue JM. Org. Lett. 2007, 9: 903 - 2
Liu Y.Nan FJ. Tetrahedron Lett. 2010, 51: 1374 -
3a
Deng LS.Ma ZX.Zhang YZ.Zhao G. Synlett 2007, 87 -
3b
Deng LS.Ma ZX.Zhao G. Synlett 2008, 728 -
3c
Ye ZQ.Deng LS.Qian S.Zhao G. Synlett 2009, 2469 -
3d
Wu H.Zhang HL.Zhao G. Tetrahedron 2007, 63: 6454 - 4
Kwabata J.Fukushi Y.Tahara S.Mizutani J. Phytochemistry 1990, 29: 2332 -
5a
Micheli RA.Hajos ZG.Cohen N.Parrish DR.Portland LA.Sciamanna W.Scott MA.Wehrli PA. J. Org. Chem. 1975, 40: 675 -
5b
Isaacs RCA.Grandi MJD.Danishefsky SJ. J. Org. Chem. 1993, 58: 3938 ; and references therein -
6a
Corey EJ.Huang AX. J. Am. Chem. Soc. 1999, 121: 710 -
6b
Daniewski AR.Kiegiel J. J. Org. Chem. 1988, 53: 5534 - 7
Hwu JR.Wetzel JM. J. Org. Chem. 1985, 50: 3946 - 8
Ito Y.Hirao T.Saegusa T. J. Org. Chem. 1978, 43: 1011 - 9
Yadav VK.Kapoor KK. Tetrahedron 1995, 51: 8573 -
10a
Hoveyda AH.Evans DA.Fu GC. Chem. Rev. 1993, 93: 1307 -
10b
Lebel H.Marcoux JF.Molinaro C.Charette AB. Chem. Rev. 2003, 103: 977 - 11
Wharton PS.Bohlen DH. J. Org. Chem. 1961, 26: 3615 - 12
Grandi MJD.Coburn CA.Isaacs RCA.Danishefsky SJ. J. Org. Chem. 1993, 58: 7728 - 13
Charette AB.Lebel H. J. Org. Chem. 1995, 60: 2966 - 16
Thompson CF.Jamison TF.Jacobsen EN. J. Am. Chem. Soc. 2000, 122: 10482 -
17a
Nair V.Sinhababu A. J. Org. Chem. 1978, 43: 5013 -
17b
Caglioti L. Tetrahedron 1966, 22: 487 - 18
Dess DB.Martin JC. J. Org. Chem. 1983, 48: 4155 - 19
Tatsuta K.Shohei Y.Kurihara K.Tanabe K.Shinei R.Okonogi T. Tetrahedron Lett. 1997, 38: 1439
References and Notes
The same operative procedure should be conducted to ensure that the starting material is completely consumed. For details, see the Supporting Information.
15See the Supporting Information for details. CCDC 804060 (4) and 804061 (14) contain the supplementary crystallogra-phic data for this paper. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
20
Data of the Core
Fragment 4
[α]D
²8 56.2
(c 0.12, CHCl3); mp 133-135 ˚C.
IR (film): 2921, 2850, 1735, 1464, 1374, 1265, 1045 cm-¹. ¹H
NMR (400 MHz, CDCl3): δ = 6.16 (s,
1 H), 4.39 (t, J = 5.2
Hz, 1 H), 2.60-2.40 (m, 2 H), 2.20-2.10 (m, 1
H), 1.89 (s, 3 H), 1.80-1.65 (m, 1 H), 1.65-1.50
(m, 1 H), 1.30-1.20 (m, 1 H), 1.09 (s, 3 H), 0.91 (s, 9
H), 1.80-1.65 (m, 1 H), 0.10 (s, 3 H), 0.07 (s, 3 H). ¹³C
NMR (100 MHz, CDCl3): δ = 171.2, 149.4, 149.3,
122.1, 121.0, 72.9, 61.9, 42.1, 29.1, 26.2, 25.8, 23.3, 21.4, 18.2,
12.1, 8.5, -4.7, -5.3. ESI-MS: m/z = 369.2 [M + Na]+.
ESI-HRMS: m/z calcd for C20H30O3SiNa+ [M + Na]+: 369.1862;
found: 369.1856.