The Catalytic Asymmetric Claisen Rearrangement (CAC) in Natural Product Synthesis: Synthetic Studies toward Curvicollides A-C

Abstract

A catalytic asymmetric Claisen rearrangement has been utilized as key C-C connecting transformation for the synthesis of a building block in the projected total synthesis of the fungicidal polyketides curvicollide A-C.

Key words

total synthesis - natural products - asymmetric catalysis - pericyclic reactions - Lewis acids

References and Notes

• 1 Che Y. Gloer JB. Wicklow DT. Org. Lett.  2004,  1249 
• 2 Ziegler FE. Chem. Rev.  1988,  1423 
• For reviews concerning the asymmetric Claisen rearrange-ment, see:
• 3a Enders D. Knopp M. Schiffers R. Tetrahedron: Asymmetry  1996,  7:  1847 
• 3b Ito H. Taguchi T. Chem. Soc. Rev.  1999,  28:  43 
• 3c Nubbemeyer U. Synthesis  2003,  961 
• 4a Abraham L. Körner M. Hiersemann M. Tetrahedron Lett.  2004,  3647 
• 4b Abraham L. Körner M. Schwab P. Hiersemann M. Adv. Synth. Catal.  2004,  1281 
• 4c Hiersemann M. Abraham L. Eur. J. Org. Chem.  2002,  1461 
• 4d Abraham L. Czerwonka R. Hiersemann M. Angew. Chem. Int. Ed.  2001,  4700 
• 5 Prepared according to: Gois PMP. Afonso CAM. Eur. J. Org. Chem.  2003,  3798 
• 6 Miller DJ. Moody CJ. Tetrahedron  1995,  51:  10811 
• 7 Gao Y. Klunder JM. Hanson RM. Masamune H. Ko SY. Sharpless KB. J. Am. Chem. Soc.  1987,  109:  5765 
• The sequence of OH-insertion and olefination was originally developed and utilized by Ganem and Berchtold for the synthesis of chorismate und its derivatives, see:
• 10a Ganem B. Ikota N. Muralidharan VB. Wade WS. Young SD. Yukimoto Y. J. Am. Chem. Soc.  1982,  104:  6787 
• 10b Pawlak JL. Berchtold GA. J. Org. Chem.  1987,  52:  1765 
• 10c Lesuisse D. Berchtold GA. J. Org. Chem.  1988,  53:  4992 
• 10d Wood HB. Buser HP. Ganem B. J. Org. Chem.  1992,  57:  178 
• 10e Mattia KM. Ganem B. J. Org. Chem.  1994,  59:  720 
• 10f For an intramolecular application, see: Kim S. Sutton SC. Guo C. LaCour TG. Fuchs PL. J. Am. Chem. Soc.  1999,  121:  2056 
• 11 Hiersemann M. Synthesis  2000,  1279 
• 12 Evans DA. Miller SJ. Lectka T. von Matt P. J. Am. Chem. Soc.  1999,  121:  7559 
• 14 Mengel A. Reiser O. Chem. Rev.  1999,  99:  1191 
• 15 Oikawa Y. Yoshioka T. Yonemitsu O. Tetrahedron Lett.  1982,  23:  885 
• 16 Corey EJ. Cho H. Rücker C. Hua DH. Tetrahedron Lett.  1981,  22:  3455 
• 17a Dess DB. Martin JC. J. Org. Chem.  1983,  48:  4155 
• 17b Dess DB. Martin JC. J. Am. Chem. Soc.  1991,  113:  7277 
• 17c Ireland RE. Liu L. J. Org. Chem.  1993,  58:  2899 

8

(E,Z)-4: ¹H NMR (300 MHz, CDCl₃): δ = 1.96 (d, 3 H, J = 7.4 Hz), 3.78 (s, 3 H), 4.09 (d, 2 H, J = 4.2 Hz), 4.31 (d, 2 H, J = 4.0 Hz), 4.50 (s, 2 H), 5.36 (q, 1 H, J = 7.4 Hz), 5.78-5.81 (m, 2 H), 7.31-7.34 (m, 5 H). ¹³C NMR (75.5 MHz, CDCl₃): δ = 12.6, 51.8, 65.0, 65.8, 72.4, 112.9, 127.7, 127.8, 128.0, 128.4, 129.7, 138.0, 144.8, 164.1. IR (neat): 3035-3030, 2950-2860, 1725 cm^-1. Anal. Calcd for C₁₆H₂₀O₄: C, 69.54; H, 7.30. Found: C, 69.21; H, 7.39.

9

Preparative HPLC: Nu 50-7, 32 × 250 mm, heptane-EtOAc 9:1, 30 ml/min, t _R (Z) = 7 min, t _R (E) = 9 min, baseline separation with 400 mg/injection.

13

(3R,4R)-3: ¹H NMR (300 MHz, CDCl₃): δ = 1.08 (d, 3 H, J = 6.9 Hz), 2.83 (m, 1 H), 3.31-3.39 (m, 2 H), 3.45 (dd^AB, 1 H, J = 9.6, 4.9 Hz), 3.62 (s, 3 H), 4.33 (d^AB, 1 H, J = 12.0 Hz), 4.37 (d^AB, 1 H, J = 12.0 Hz), 5.12-5.17 (m, 2 H), 5.45-5.58 (m, 1 H), 7.22-7.34 (m, 5 H). ¹³C NMR (75.5 MHz, CDCl₃): δ = 14.4, 43.1, 48.4, 52.5, 72.4, 72.7, 118.7, 127.6, 128.3, 135.3, 137.5, 161.5, 195.6. IR (neat): ν = 3300-3150, 2950-2870, 1728 cm^-1. Anal. Calcd for C₁₆H₂₀O₄: C, 69.54; H, 7.30. Found: C, 69.28; H, 7.38. [α]²⁵ _D +39.7 (c 0.89, CHCl₃).

18

(3R,4R,5R)-2: ¹H NMR (300 MHz, CDCl₃): δ = 0.00 (s, 3 H), 0.05 (s, 3 H), 0.75 (d, 3 H, J = 7.1 Hz), 0.94 (s, 9 H), 2.03-2.12 (m, 1 H), 2.14 (s, 3 H), 2.71-2.79 (m, 1 H), 3.46 (dd^AB, 1 H, J = 9.7, 7.2 Hz), 3.53 (dd^AB, 1 H, J = 9.7, 6.1 Hz), 3.79 (d, 1 H, J = 7.7 Hz), 4.45 (d^AB, 1 H, J = 12.1 Hz), 4.55 (d^AB, 1 H, J = 12.1 Hz), 5.04-5.14 (m, 2 H), 5.71 (ddd, 1 H, J = 17.2, 10.5, 8.8 Hz), 7.29-7.41 (m, 5 H). ¹³C NMR (75.5 MHz, CDCl₃): δ = -5.0, -4.8, 11.3, 18.1, 25.3, 25.8, 37.0, 42.8, 71.6, 72.6, 81.4, 117.5, 127.5, 127.6, 128.3, 136.2, 138.5, 211.7. IR (neat): ν = 3100-3060, 2970-2860, 1716 cm^-1. Anal. Calcd for C₂₂H₃₆O₃Si: C, 70.16; H, 9.63. Found: C, 70.30; H, 9.72. [α]²⁵ _D +38.3 (c 0.90, CHCl₃).