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DOI: 10.1055/s-0029-1218565
Synthesis of the C1-C15 Region of Palmerolide A Using Refined Claisen-Type Addition-Bond Cleavage Methodology
Publication History
Publication Date:
11 December 2009 (online)
Abstract
Synthesis of the eastern hemisphere (C1-C15) of palmerolide A is described. A re-optimized Claisen-type condensation of vinylogous acyl triflates provides efficient entry into the C1-C8 subunit, setting up a convergent Horner-Wittig olefination to deliver the eastern portion of palmerolide A.
Key words
vinylogous acyl triflate - fragmentation - total synthesis - palmerolide - methodology
- Supporting Information for this article is available online:
- Supporting Information
- 1
Amsler CD.Iken KB.McClintock JB.Baker BJ. In Marine Chemical EcologyMcClintock JB.Baker BJ. CRC Press; Boca Raton FL: 2001. p.267-300 - 2
Dayton PK.Mordida BJ.Bacon F. Am. Zool. 1994, 34: 90 -
4a
Diyabalange T.Amsler CD.McClintock JB.Baker BJ. J. Am. Chem. Soc. 2006, 128: 5630 -
4b
Lebar MD.Baker BJ. Tetrahedron Lett. 2007, 48: 8009 -
4c
Riesenfeld CS.Murray AE.Baker BJ. J. Nat. Prod. 2008, 71: 1812 -
6a
Jiang X.Liu B.Lebreton S.De Brabander JK.
J. Am. Chem. Soc. 2007, 129: 6386 -
6b
Nicolaou KC.Guduru R.Sun Y.-P.Banerji B.Chen DY.-K. Angew. Chem. Int. Ed. 2007, 46: 5896 -
6c
Jägel J.Maier ME. Synthesis 2009, 2881 -
6d
Kaliappan KP.Gowrisankar P. Synlett 2007, 1537 -
6e
Cantragrel G.Meyer C.Cossy J. Synlett 2007, 2983 -
6f
Chandrasekhar S.Vijeender K.Chandrasekhar G.Reddy ChR. Tetrahedron: Asymmetry 2007, 18: 2473 -
6g
Jägel J.Schmauder A.Binanzer M.Maier ME. Tetrahedron 2007, 63: 13006 -
6h
Penner M.Rauniyar V.Kaspar LT.Hall DG. J. Am. Chem. Soc. 2009, 131: 14216 -
7a
Kamijo S.Dudley GB. J. Am. Chem. Soc. 2005, 127: 5028 -
7b
Jones DM.Kamijo S.Dudley GB. Synlett 2006, 936 -
7c
Kamijo S.Dudley GB. J. Am. Chem. Soc. 2006, 128: 6499 -
7d
Kamijo S.Dudley GB. Org. Lett. 2006, 8: 175 -
8a
Eschenmoser A.Felix D.Ohloff G. Helv. Chim. Acta 1967, 50: 708 -
8b
Felix D.Shreiber J.Ohloff G.Eschenmoser A. Helv. Chim. Acta 1971, 54: 2896 -
8c
Tanabe M.Crowe DF.Dehn RL. Tetrahedron Lett. 1967, 3943 -
8d
Tanabe M.Crowe DF.Dehn RL.Detre G. Tetrahedron Lett. 1967, 3739 -
9a
Grob CA.Schiess PW. Angew. Chem., Int. Ed. Engl. 1967, 6: 1 -
9b
Grob CA. Angew. Chem., Int. Ed. Engl. 1969, 8: 535 -
9c
Wharton PS.Hiegel GA. J. Org. Chem. 1965, 30: 3254 -
9d
Weyerstahl P.Marschall H. In Comprehensive Organic Synthesis Vol. 6:Trost BM.Fleming I. Pergamon; Oxford: 1991. p.1041-1070 -
10a For
a recent application of the fragmentation of vinyl triflates to
the synthesis of allenes, see:
Kolakowski RV.Manpadi M.Zhang Y.Emge TJ.Williams LJ. J. Am. Chem. Soc. 2009, 131: 12910 -
10b For application of a related
ring fragmentation to the synthesis of tethered alkynyl aldehydes,
see:
Draghici C.Brewer M. J. Am. Chem. Soc. 2008, 130: 3766 - 11
Tummatorn J.Dudley GB. J. Am. Chem. Soc. 2008, 130: 5050 - 12 For a recent report on the synthesis
of β-ketophosphonates using the classical Claisen condensation,
with leading references, see:
Maloney KM.Chung JYL. J. Org. Chem. 2009, 74: 7574 -
14a
Fürstner A.Langemann K. J. Am. Chem. Soc. 1997, 119: 9130 -
14b
Michaunt A.Boddaert T.Coquerel Y.Rodriguez J. Synthesis 2007, 18: 2687 -
15a
Sharpless KB.Amberg W.Bennani YL.Crispino GA.Hartung J.Jeong KS.Kwong HL.Morikowa K.Wang ZM.Xu D.Zhang X.-L. J. Org. Chem. 1992, 57: 2768 -
15b For a similar reaction,
see:
Gurjar MK.Pramanik C.Bhattasali D.Ramana CV.Mohapatra DK. J. Org. Chem. 2007, 72: 6591 - 16 Prepared in two steps (one pot)
from 4-pentynol (85% yield), see:
Vatele J.-M. Tetrahedron Lett. 2006, 47: 715 - 19
Corey EJ.Helal CJ. Angew. Chem. Int. Ed. 1998, 37: 1986
References and Notes
Information available through the Antarctic Treaty Secretariat: http://www.ats.aq/.
5Of the NCI’s panel of 60 cancer
cell lines, no other cell
line registered a cytotoxic
response below micromolar concentrations.
See Supporting Information, compound A.
17See Supporting Information, compound B.
18Cyclization of 5 predominated using bases including Ba(OH)2, DBU˙LiCl (Masamune-Roush conditions), and KOt-Bu. A common feature of these bases is that each is intermediate in basicity between the initial β-keto phosphine oxide anion and the enolate arising from undesired cyclization onto the enoate. Therefore, the conjugate acid may play a role in promoting undesired cyclization (Scheme [³] ).
20See Supporting Information, compound C.