Selectivity in Cobalt Carbonyl Mediated Cycloaddition of Dienynes

Kang Hyun Park; Soo Young Choi; So Yeon Kim; Young Keun Chung

doi:10.1055/s-2006-932466

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Synlett 2006(4): 0527-0532
DOI: 10.1055/s-2006-932466

LETTER

Selectivity in Cobalt Carbonyl Mediated Cycloaddition of Dienynes

Kang Hyun Park, Soo Young Choi, So Yeon Kim, Young Keun Chung*
Intelligent Textile System Research Center, and Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 151-747, Korea
Fax: +82(2)8890310; e-Mail: ykchung@snu.ac.kr;

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Publication History

Received 25 October 2005
Publication Date:
20 February 2006 (online)

Abstract
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Abstract

Dicobalt octacarbonyl mediated cycloaddition of dienynes in the presence of carbon monoxide has been studied. Three main competing reaction routes, two carbonylative cycloaddition reactions and a Diels-Alder reaction, have been recognized depending upon the substrate and reaction conditions. Judicious design of the substrate and selection of reaction conditions allow control of the reaction pathway.

Key words

cobalt carbonyl - cycloadditions - dienynes - carbon monoxide - Diels-Alder

References and Notes

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9

Crystal data for 2a: monoclinic, P2₁/a, a = 11.7068 (14), b = 15.7393 (17), c = 13.9213 (12) Å, β = 90.707 (6)°, limiting indices -11 £ h £ 14, -15 £ k £ 18, -15 £ l £ 17, reflections collected/unique 12136/4429 (R _int = 0.2320), final R indices [I > 2σ(I)] R1 = 0.0831, wR2 = 0.1130. For 5h: triclinic, P-1, a = 6.5446 (3), b = 11.3786 (9), c = 13.9632 (13)Å, α = 105.233 (3), β = 99.165 (5), γ = 101.332 (4)°, limiting indices -5 £ h £ 8, -14 £ k £ 11, -15 £ l £ 18, reflections collected/unique 5277/4305 (R _int = 0.0246), final R indices [I > 2σ(I)] R1 = 0.0577, wR2 = 0.1240. Crystallographic data for 2a and 5h have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication numbers of CCDC 287305 and 287306, respectively. These data can be obtained free charge via www.ddcd.cam.ac.uk/consts/retrieving.html [or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB21EZ, UK; fax: +44 (1223)336033; or deposit@ddcd.cam.ac.uk].

10

General Comments.
Thin-layer chromatography (TLC) was performed on 0.25 mm Merck silica gel coated plates treated with a UV (254 nm) and acidic p-anisaldehyde stain followed by gentle heating. TLC plates were visualized by ultraviolet light and treatment with acidic p-anisaldehyde staining solution. THF was purified by distillation from sodium/benzophenone under nitrogen, toluene was distilled from sodium under nitrogen, CH₂Cl₂ was distilled form P₂O₅ under nitrogen. Reagents were purchased from Aldrich Chemical Co. and Strem Chemical Co. and were used as received. All yields are based upon isolated material. ¹H NMR and ¹³C NMR spectra were obtained with a Bruker 300 MHz spectrometer. Coupling constants (J values) are reported in Hertz (Hz), and spin multiplicities are indicated by the following symbols: s(singlet), d(doublet), t(triplet), q(quartet), m(multiplet). Infrared spectra were recorded on a Shimadzu IR-470 spectrometer. IR spectra were obtained as films on NaCl by evaporation of solvent or in CHCl₃ solution. Elemental analyses were done at the National Center for Inter-University Research Facilities, Seoul National University. High resolution mass spectra were obtained at Korea Basic Science Institute (Daegu, Korea). High resolution mass spectrometry (HRMS) data are reported in the form of m/z (intensity relative to base peak = 100). Microwave reactions were carried out on a CEM Discover microwave reactor with a circular, single mode, self-tuning microwave applicator operating at 2450 MHz. The reaction vessel was purged with nitrogen prior to the addition of reagents. Flash chromatography was performed using Merck Silica Gel 60 (230-400 mesh). Diffraction data of 2a and 5h for structure determination were measured by an Enraf-Nonius CCD single-crystal X-ray diffractometer at r.t. using graphite-monochromated MoK_α radiation (λ = 0.71013 Å). Preliminary orientation matrixes and unit cell parameters were obtained from the peaks of the first 10 frames and then refined using the whole data set. Frames were integrated and corrected for Lorentz and polarization effects using DENZO. The structure was solved by direct methods using SHELXS-97 and refined by full-matrix least squares fitting with SHELXL-97. All non-hydrogen atoms were refined anisotropically, and all hydrogen atoms not involving hydrogen bonding were treated as idealized contributions.
Analytical Data.
6-Phenyl-4-propenyl-3a,4-dihydro-1 H ,3 H -cyclo-penta[ c ]furan-5-one (2a).
¹H NMR (CDCl₃): δ = 1.77 (d, J = 4.9 Hz, 3 H), 2.96 (m, 1 H), 3.24 (m, 1 H), 3.32 (dd, J = 7.6, 11.0 Hz, 1 H), 4.43 (t, J = 7.4 Hz, 1 H), 4.61 (d, J = 16.5 Hz, 1 H), 4.93 (dd, J = 1.5, 16.5 Hz, 1 H), 5.67 (m, 2 H), 7.36 (m, 3 H), 7.53 (m, 2 H) ppm. ¹³C NMR (CDCl₃): δ = 18.3, 50.4, 56.5, 66.7, 71.4, 126.4, 128.2, 128.8, 128.9, 130.0,130.9, 133.5, 174.6, 206.6 ppm. IR: ν_CO = 1706 cm^-1. HRMS: m/z calcd for C₁₆H₁₆O₂: 240.1150; found: 240.1151. Anal. Calcd for C₁₆H₁₆O₂: C, 79.96; H, 6.72. Found: C, 80.17; H, 6.88.
6-Butyl-4-propenyl-3a,4-dihydro-1 H ,3 H -cyclo-penta[ c ]furan-5-one (2b).
¹H NMR (CDCl₃): δ = 0.90 (t, J = 7.2 Hz, 3 H), 1.31 (m, 2 H), 1.43 (m, 2 H), 1.75 (d, J = 5.8 Hz, 3 H), 2.14 (qui, J = 7.4 Hz, 1 H), 2.27 (qui, J = 7.4 Hz, 1 H) 2.74 (m, 1 H), 3.08 (m, 1 H), 3.27 (dd, J = 8.0, 11.1 Hz, 1 H), 4.36 (t, J = 7.8 Hz, 1 H), 4.51 (dd, J = 0.7, 15.7 Hz, 1 H), 4.61 (dd, J = 1.1, 15.7 Hz, 1 H), 5.60 (m, 2 H) ppm. ¹³C NMR (CDCl₃): δ = 14.0, 18.4, 22.8, 24.5, 30.0, 50.4, 55.1, 65.3, 71.8, 126.6, 129.7, 135.7, 173.5, 208.9 ppm. IR: ν_CO = 1707 cm^-1. HRMS: m/z calcd for C₁₄H₂₀O₂: 220.1463; found: 220.1467.
6-Phenyl-4-propenyl-2-(toluene-4-sulfonyl)-2,3,3a,4-tetrahydro-1 H -cyclopenta[ c ]pyrrol-5-one (2c).
¹H NMR (CDCl₃): δ = 1.75 (d, J = 6.0 Hz, 3 H), 2.40 (s, 3 H), 2.66 (dd, J = 9.3, 10.8 Hz, 1 H), 2.86 (m, 1 H), 3.14 (m, 1 H), 4.06 (m, 1 H), 4.13 (d, J = 8.7 Hz, 1 H), 4.65 (dd, J = 1.7, 17.1 Hz, 1 H), 5.60 (m, 2 H), 7.31 (d, J = 8.1 Hz, 2 H), 7.35-7.47 (m, 5 H), 7.72 (d, J = 8.3 Hz, 2 H) ppm. ¹³C NMR (CDCl₃): δ = 14.3, 18.4, 21.7, 22.8, 31.8, 48.6, 48.8, 51.9, 56.9, 125.8, 127.6, 128.3, 128.9, 129.1, 130.1, 130.2, 130.4, 133.6, 134.9, 144.3, 169.3, 205.4 ppm. IR: ν_CO = 1709 cm^-1. HRMS: m/z calcd for C₂₃H₂₃O₃NS: 393.1399; found: 393.1400.
4-Propenyl-2-(toluene-4-sulfonyl)-2,3,3a,4-tetrahydro-1 H -cyclopenta[ c ]pyrrol-5-one (2d).
¹H NMR (CDCl₃): δ = 1.73 (d, J = 7.2 Hz, 3 H), 2.45 (s, 3 H), 2.64-2.72 (m, 2 H), 3.07 (m, 1 H), 3.97-4.10 (m, 2 H), 4.35 (d, J = 16.8 Hz, 1 H), 5.45 (m, 1 H), 5.59 (m, 1 H), 5.98 (s, 1 H), 7.36 (d, J = 8.0 Hz, 2 H), 7.74 (d, J = 8.3 Hz, 2 H) ppm. ¹³C NMR (CDCl₃): δ = 18.4, 21.8, 47.9, 50.5, 52.2, 56.1, 124.9, 125.5, 127.7, 130.2, 130.6, 133.4, 144.4, 176.6, 207.5 ppm. IR: ν_CO = 1710 cm^-1. HRMS: m/z calcd for C₁₇H₁₉O₃NS: 317.1086; found: 317.1085.
5-Oxo-6-phenyl-4-propenyl-3,3a,4,5-tetrahydro-1 H -pentalene-2,2-dicarboxylic Acid Diethyl Ester (2e).
¹H NMR (CDCl₃): δ = 1.07 (t, J = 7.1 Hz, 3 H), 1.15 (t, J = 7.1 Hz, 3 H), 1.60 (d, J = 5.8 Hz, 3 H), 1.70 (t, J = 12.4 Hz, 1 H), 2.69-2.78 (m, 2 H), 2.87 (m, 1 H), 3.16 (d, J = 19.5 Hz, 1 H), 3.50 (d, J = 19.4 Hz, 1 H), 4.01 (m, 2 H), 4.13 (dd, J = 7.0, 14.1 Hz, 2 H), 5.42 (m, 1 H), 5.54 (m, 1 H), 7.12-7.43 (m, 5 H) ppm. ¹³C NMR (CDCl₃): δ = 14.1, 14.2, 18.3, 36.1, 38.4, 50.0, 58.8, 61.3, 61.5, 62.10, 62.13, 63.3, 126.8, 128.3, 128.48, 128.55, 129.6, 131.2, 134.3, 170.8, 171.7, 176.2, 206.8 ppm. IR: ν_CO = 1723 cm^-1. HRMS: m/z calcd for C₂₃H₂₆O₅: 382.1780; found: 382.1780.
6-Methyl-5-oxo-4-propenyl-3,3a,4,5-tetrahydro-1 H -pentalene-2,2-dicarboxylic Acid Diethyl Ester (2f).
¹H NMR (CDCl₃): δ = 1.21 (m, 6 H), 1.65-1.67 (m, 6 H), 1.73 (m, 1 H), 2.64 (m, 1 H), 2.77 (m, 2 H), 3.13 (dd, J = 18.9, 28.1 Hz, 2 H), 4.16 (m, 4 H), 5.41 (m, 1 H), 5.56 (m, 1 H) ppm. ¹³C NMR (CDCl₃): δ = 9.0, 14.2, 18.4, 34.1, 38.8, 49.8, 57.5, 61.1, 62.1, 62.3, 127.1, 129.4, 131.9, 171.2, 175.5, 209.2 ppm. IR: ν_CO = 1722 cm^-1. HRMS: m/z calcd for C₁₈H₂₄O₅: 320.1624; found: 320.1621.
5-Oxo-4-propenyl-3,3a,4,5-tetrahydro-1 H -pentalene-2,2-dicarboxylic Acid Diethyl Ester ( 2g).
¹H NMR (CDCl₃): δ = 1.28 (m, 6 H), 1.74 (d, J = 6.2 Hz, 3 H), 1.84 (t, J = 12.5 Hz, 1 H), 2.78 (m, 1 H), 2.84 (dd, J = 7.8, 12.8 Hz, 1 H), 3.00 (m, 1 H), 3.30 (dd, J = 19.1, 36.9 Hz, 2 H), 4.24 (m, 4 H), 5.48 (m, 1 H), 5.63 (m, 1 H), 5.93 (m, 1 H) ppm. ¹³C NMR (CDCl₃): δ = 14.2, 18.3, 35.3, 38.5, 51.8, 58.4, 61.0, 62.2, 62.3, 124.4, 126.6, 129.8, 170.1, 171.6, 183.3, 209.4 ppm. IR: ν_CO = 1723 cm^-1. HRMS: m/z calcd for C₁₇H₂₂O₅: 306.1467; found: 306.1466.
7-Phenyl-2-(toluene-4-sulfonyl)-2,3,3a,6-tetrahydro-1 H -isoindole (3h). ¹H NMR (CDCl₃): δ = 2.35 (s, 3 H), 2.63 (dd, J = 11.2, 8.8 Hz, 1 H), 2.83-2.88 (m, 1 H), 2.96-2.99 (m, 1 H), 3.05-3.22 (m, 1 H), 3.63 (d, J = 14.0 Hz, 1 H), 3.80 (dd, J = 8.7, 7.7 Hz, 1 H), 4.07-4.14 (m, 1 H), 5.67 (d, J = 10.3 Hz, 1 H), 5.80-5.86 (m, 1 H), 7.05 (d, J = 8.3 Hz, 2 H), 7.19-7.27 (m, 1 H), 7.58 (d, J = 8.3 Hz, 2 H) ppm. HRMS: m/z calculated for C₂₁H₂₁O₂SN: 351.1293; found: 351.1296. Anal. Calcd for C₂₁H₂₁O₂SN: C, 71.77; H, 6.02; N, 3.99. Found: C, 71.80; H, 5.69; N, 3.45.
7-Butyl-2-(toluene-4-sulfonyl)-2,3,3a,6-tetrahydro-1 H -isoindole (3i). ¹H NMR (CDCl₃): δ = 0.87 (t, J = 7.1 Hz, 3 H), 1.21-1.31 (m, 4 H), 1.81-2.01 (m, 2 H), 2.42 (s, 3 H), 2.45-2.53 (m, 1 H), 2.57 (dd, J = 11.5, 8.6 Hz, 2 H), 2.93-3.11 (m, 1 H), 3.79-3.84 (m, 2 H), 3.97 (d, J = 13.2 Hz, 1 H), 5.65 (d, J = 9.9 Hz, 2 H), 5.75-5.81 (m, 1 H), 7.31 (d, J = 8.0 Hz, 2 H), 7.72 (d, J = 8.2 Hz, 2 H) ppm. ¹³C NMR (CDCl₃): δ = 14.3, 19.0, 23.2, 29.1, 30.5, 33.5, 49.1, 52.9, 55.5, 127.2, 127.8, 128.7, 128.9, 129.9, 131.1 ppm. HRMS: m/z calcd for C₁₉H₂₅O₂SN: 331.1606; found: 331.1601.
2-(Toluene-4-sulfonyl)-2,3,3a,6-tetrahydro-1 H -isoindole (3j). ¹H NMR (CDCl₃): δ = 2.42 (s, 3 H), 2.62-2.70 (m, 3 H), 2.98 (t, J = 8.3 Hz, 1 H), 3.73 (d, J = 13.1 Hz, 1 H), 3.83 (t, J = 8.3 Hz, 1 H), 3.98-4.04 (m, 1 H), 5.50-5.58 (m, 1 H), 5.62-5.69 (m, 1 H), 5.72-5.83 (m, 1 H), 7.31 (d, J = 8.4 Hz, 2 H), 7.71 (d, J = 8.3 Hz, 2 H) ppm.
( E )-4-Ethylidene-6-phenyl-2-(toluene-4-sulfonyl)-2,3,3a,4-tetrahydro-1 H -cyclopenta[ c ]pyrrol-5-one (5h). ¹H NMR (CDCl₃): δ = 1.92 (d, J = 7.2 Hz, 3 H), 2.40 (s, 3 H), 2.60 (dd, J = 10.9, 9.0 Hz, 1 H), 3.74 (t, J = 8.6 Hz, 1 H), 4.03 (dd, J = 16.3, 1.5 Hz, 1 H), 4.22 (t, J = 8.6 Hz, 1 H), 4.66 (dd, J = 16.3, 1.7 Hz, 1 H), 6.79 (qd, J = 7.2, 1.9 Hz, 1 H), 7.29 (d, J = 8.2 Hz, 2 H), 7.37-7.45 (m, 3 H), 7.49-7.53 (m, 2 H), 7.70 (d, J = 8.3 Hz, 2 H) ppm. ¹³C NMR (CDCl₃): δ = 15.8, 21.7, 44.8, 48.1, 50.1, 127.5, 128.4, 128.8, 129.1, 130.2, 130.6, 132.9, 133.9, 137.2, 137.7, 144.2, 165.8, 195.3 ppm. IR: ν_CO = 1699 cm^-1. HRMS: m/z calcd for C₂₂H₂₁O₃SN: 379.1242; found: 379.1242. Anal. Calcd for C₂₂H₂₁O₃SN: C, 69.63; H, 5.58; N, 5.58. Found: C, 69.73; H, 6.02; N, 3.26.
( E )-6-Butyl-4-ethylidene-2-(toluene-4-sulfonyl)-2,3,3a,4-tetrahydro-1 H -cyclopenta[ c ]pyrrol-5-one (5i). ¹H NMR (CDCl₃): δ = 0.77 (t, J = 7.2 Hz, 3 H), 1.04-1.18 (m, 2 H), 1.21-1.30 (m, 2 H), 1.78 (d, J = 7.1 Hz, 3 H), 1.96-2.05 (m, 1 H), 2.11-2.21 (m, 1 H), 2.36 (s, 3 H), 2.46 (dd, J = 10.9, 9.0 Hz, 1 H), 3.48 (t, J = 9.0 Hz, 1 H), 3.91 (d, J = 15.5 Hz, 1 H), 4.05 (t, J = 8.5 Hz, 1 H), 4.19 (d, J = 15.6 Hz, 1 H), 6.56 (qd, J = 7.13, 1.6 Hz, 1 H), 7.27 (d, J = 8.1 Hz, 2 H), 7.66 (d, J = 8.2 Hz, 2 H) ppm. ¹³C NMR (CDCl₃): δ = 13.9, 15.7, 21.7, 22.6, 24.2, 30.0, 44.5, 46.5, 50.8, 127.6, 130.1, 131.7, 133.6, 136.7, 140.2, 144.2, 164.3, 195.3 ppm. IR: ν_CO = 1698 cm^-1. HRMS: m/z calcd for C₂₀H₂₅O₃SN: 359.1555; found: 359.1550.
( Z )-4-Ethylidene-6-phenyl-2-(toluene-4-sulfonyl)-2,3,3a,4-tetrahydro-1 H -cyclopenta[ c ]pyrrol-5-one (6h). ¹H NMR (CDCl₃): δ = 2.27 (dd, J = 7.4, 1.1 Hz, 3 H), 2.40 (s, 3 H), 2.57 (dd, J = 10.8, 9.0 Hz, 1 H), 3.67 (t, J = 9.9 Hz, 1 H), 4.02 (dd, J = 16.5, 1.5 Hz, 1 H), 4.05 (t, J = 8.6 Hz, 1 H), 4.65 (dd, J = 16.4, 1.7 Hz, 1 H), 6.18 (qd, J = 7.4, 1.4 Hz, 1 H), 7.30 (d, J = 8.2 Hz, 2 H), 7.37-7.44 (m, 3 H), 7.49-7.52 (m, 2 H), 7.70 (d, J = 8.3 Hz, 2 H) ppm. ¹³C NMR (CDCl₃): δ = 14.3, 23.9, 46.8, 48.5, 50.7, 127.6, 128.5, 130.2, 130.7, 131.1, 132.7, 133.9, 135.9, 136.9, 138.9, 144.2, 167.9, 194.8 ppm. IR: ν_CO = 1694 cm^-1. HRMS: m/z calcd for C₂₂H₂₁O₃SN: 379.1242; found: 379.1239.
( Z )-6-Butyl-4-ethylidene-2-(toluene-4-sulfonyl)-2,3,3a,4-tetrahydro-1 H -cyclopenta[ c ]pyrrol-5-one (6i). ¹H NMR (CDCl₃): δ = 0.76-0.81 (m, 3 H), 1.10-1.30 (m, 4 H), 1.44-1.58 (m, 2 H), 2.12 (d, J = 7.4 Hz, 3 H), 2.36 (s, 3 H), 2.44 (dd, J = 10.8, 8.9 Hz, 1 H), 3.40 (t, J = 9.1 Hz, 1 H), 3.86-3.93 (m, 2 H), 4.13-4.17 (m, 1 H), 5.60 (qd, J = 7.4, 1.2 Hz, 1 H), 7.27 (d, J = 8.0 Hz, 2 H), 7.65 (d, J = 8.0 Hz, 2 H) ppm. ¹³C NMR (CDCl₃): δ = 11.1, 13.9, 21.7, 22.7, 24.1, 30.0, 38.9, 46.9, 51.4, 127.6, 130.1, 131.1, 135.2, 135.9, 141.4, 144.2, 163.9 ppm. IR: ν_CO = 1692 cm^-1. HRMS: m/z calcd for C₂₀H₂₅O₃SN: 359.1555; found: 359.1553.