Synlett 2010(8): 1223-1226  
DOI: 10.1055/s-0029-1219807
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Catalytic Activity Studies of Aminocarbonyl Group Containing Hoveyda-Grubbs-Type Complexes for the Syntheses of Herbarumin I and Stagonolide A

Debendra K. Mohapatra*a, R. Somaiaha, M. Mallikarjuna Raoa, Fréderic Caijob, Marc Mauduit*b, J. S. Yadav*a
a Organic Chemistry Division-I, Indian Institute of Chemical Technology (CSIR), Uppal Road, Hyderabad 500 007, India
Fax: +91(40)27160512; e-Mail: mohapatra@iict.res.in;
b Ωcat SYSTEM®, Ecole Nationale Supérieure de Chimie de Rennes, Av. Du Général Leclerc, 35700 Rennes, France
Further Information

Publication History

Received 2 March 2010
Publication Date:
09 April 2010 (online)

Abstract

The catalytic activity of four aminocarbonyl group containing ‘boomerang’-type ring-closing metathesis catalysts have been studied for ten-membered lactone and compared well with the Grubbs I and II as well as the Hoveyda-Grubbs catalysts. The activity was found to be superior to the above three ring-closing metathesis catalysts and suggesting novel stereoselective total syntheses of herbarumin I and stagonolide A.

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Analytical and Spectral Data of 10
[α]D ²5 +7.6 (c 1.1, CHCl3). IR (neat): 3455, 2924, 2852, 2097, 1461 cm. ¹H NMR (300 MHz, CDCl3): δ = 7.43-7.19 (m, 5 H), 6.05 (m, 1 H), 5.34 (dd, J = 17.3, 1.5 Hz, 1 H), 5.18 (dd, J = 10.6, 1.5 Hz, 1 H), 4.60 (ABq, J = 13.6, 11.3 Hz, 2 H), 4.31 (t, J = 5.3 Hz, 1 H), 3.74 (m, 1 H), 3.25 (t, J = 6.04 Hz, 1 H), 2.90 (br s, 1 H), 2.59 (br s, 1 H), 1.69-1.24 (m, 4 H), 0.92 (t, J = 6.8 Hz, 3 H). ¹³C NMR (75 MHz, CDCl3): δ = 137.7, 137.9, 137.7, 128.4, 127.8, 128.1, 116.1, 84.2, 73.9, 73.7, 72.6, 35.3, 18.8, 14.0. HRMS: m/z calcd for C15H22O3Na: 273.1466; found: 273.1472.

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Analytical and Spectral Data of 11
[α]D ²5 +27.0 (c 0.7, CHCl3). IR (neat): νmax = 3398, 2963, 2925, 2855, 1723, 1711, 1639, 1461, 1129 cm. ¹H NMR (300 MHz, CDCl3): δ = 7.38-7.23 (m, 5 H), 6.02-5.68 (m,
2 H), 5.29-5.12 (m, 2 H), 5.07-4.95 (m, 2 H), 4.66 (ABq, J = 17.2, 11.5 Hz, 2 H), 4.21-4.06 (m, 2 H), 3.50 (t, J = 4.7 Hz, 1 H), 2.33-2.24 (m, 2 H), 2.14-2.06 (dd, J = 7.4, 6.9 Hz, 2 H), 1.78-1.63 (m, 4 H), 1.40-1.22 (m, 2 H), 0.96-0.84 (m, 12 H), 0.07 (s, 3 H), 0.04 (s, 3 H). ¹³C NMR (75 MHz, CDCl3): δ = 172.7, 138.5, 138.1, 137.6, 128.2, 127.8, 127.5, 116.5, 115.3, 83.9, 74.6, 74.0, 73.7, 34.9, 33.7, 33.1, 31.5, 25.8, 24.1, 18.7, 14.0, -4.2, -5.0. HRMS: m/z calcd for C27H44O4NaSi: 483.2906; found: 483.2914.

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Analytical and Spectral Data of 12
[α]D ²5 +18.2 (c 1.0, CHCl3). IR (film): νmax = 4272, 3801, 3471, 2954, 1722, 1641, 1371, 1217, 1091 cm. ¹H NMR (300 MHz, CDCl3): δ = 7.40-7.30 (m, 5 H), 5.68-5.57 (m, 1 H), 5.50 (dd, J = 15.7, 1.1 Hz, 1 H), 5.21 (dt, J = 9.5, 1.1 Hz, 1 H), 4.73-4.53 (m, 3 H), 3.37 (dd, J = 9.6, 1.9 Hz, 1 H), 2.34-2.27 (m, 2 H), 2.03-1.78 (m, 4 H), 1.49 (m, 1 H), 1.36-1.22 (m, 4 H), 0.89 (t, J = 7.4 Hz, 3 H). ¹³C NMR (75 MHz, CDCl3): δ = 175.5, 137.3, 133.1, 130.3, 128.5, 128.0, 124.6, 80.9, 72.3, 68.8, 68.8, 34.5, 33.6, 33.5, 24.5, 17.8, 13.9. HRMS: m/z calcd for C19H26O4Na: 341.1728; found: 341.1722.

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General Procedure for the Metathesis Reaction
To a stirred solution of diene (1.0 mmol) in freshly prepared dry CH2Cl2 (200 mL) at r.t. was added the metathesis catalyst (0.01 mmol) under argon. The progress of the reaction was monitored by TLC. After completion of the reaction, solvent was removed under reduced pressure. The crude product was purified by flash column chromatography (EtOAc-hexane = 1:6) to afford the E-isomer as the sole product.

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Analytical and Spectral Data of 2
[α]D ²5 +10.6 (c 1.0, EtOH); lit.:7b [α]D ²0 +10.8 (c 0.51, EtOH). ¹H NMR (300 MHz, CDCl3): δ = 5.61 (d, J = 15.9 Hz, 1 H), 5.49 (m, 1 H), 4.95 (td, J = 9.4, 2.2 Hz, 1 H), 4.42 (br s, 1 H), 3.51 (d, J = 9.8 Hz, 1 H), 2.76 (br s, 1 H), 2.45-2.25 (m, 2 H), 2.06-1.81 (m, 4 H), 1.56 (m, 1 H), 1.43-1.18 (m, 3 H), 0.91 (t, J = 7.3 Hz, 3 H). ¹³C NMR (75 MHz, CDCl3): δ = 176.3, 130.7, 124.6, 73.6, 73.3, 70.1, 34.4, 33.6, 33.3, 24.6, 17.9, 13.8. IR (neat): νmax = 3455, 3038, 2955, 2920, 2867, 1711, 1639, 1219 cm. HRMS: m/z calcd for C12H20O4Na: 251.1259; found: 251.1264.

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Analytical and Spectral Data of 1
Mp 71-72 ˚C; [α]D ²5 -59.2 (c 0.5, EtOH). ¹H NMR (300 MHz, CDCl3): δ = 6.42 (d, J = 16.0 Hz, 1 H), 6.32 (m, 1 H), 4.65 (dt, J = 9.5, 2.4 Hz, 1 H), 4.05 (dd, J = 9.5, 6.2 Hz, 1 H), 3.57 (d, J = 6.2 Hz, 1 H), 2.57-2.41 (m, 2 H), 2.20-1.90 (m, 6 H), 1.43-1.18 (m, 3 H), 0.93 (t, J = 7.2 Hz, 3 H). ¹³C NMR (75 MHz, CDCl3): δ = 199.5, 174.2, 143.1, 131.9, 76.5, 74.4, 34.2, 34.0, 33.5, 24.9, 18.0, 13.7. IR (neat): νmax = 3468, 2925, 1740, 1700, 1638, 1219 cm. HRMS: m/z calcd for C12H19O4: 227.1278; found: 227.1274.