Regiocontrolled Ruthenium-Catalyzed Isomerization of Propargyl Alcohols

Abstract

A diaminocyclopentadienone ruthenium complex allows control of regioselectivity in the ruthenium-catalyzed isomerization of propargyl alcohols through the choice of additive. Thereby, both products of the Meyer–Schuster rearrangement and redox isomerization products are selectively accessible. In the presence of hydroxylamine-O-sulfonic acid, unsaturated nitriles are formed instead. The ruthenium catalyst is readily available and stable to moisture, air, and acidic conditions.

Key words

ruthenium - Meyer–Schuster rearrangement - redox isomerization - unsaturated nitriles - propargyl alcohols

Publikationsverlauf

Eingereicht: 07. Februar 2024

Angenommen nach Revision: 14. März 2024

Accepted Manuscript online:
14. März 2024

Artikel online veröffentlicht:
02. April 2024

• References

• 1 Cadierno V, Crochet P, García-Garrido SE, Gimeno J. Dalton Trans. 2010; 4015
• 2 Meyer KH, Schuster K. Ber. Dtsch. Chem. Ges. 1922; 55: 819
• 3 Rupe H, Kambli E. Helv. Chim. Acta 1926; 9: 672
• 4 Swaminathan S, Narayanan KV. Chem. Rev. 1971; 71: 429
• 5 Engel DA, Dudley GB. Org. Biomol. Chem. 2009; 7: 4149
• 6 Edens M, Boerner D, Chase CR, Nass D, Schiavelli MD. J. Org. Chem. 1977; 42: 3403
• 7 Park J, Yun J, Kim J, Jang D.-J, Park CH, Lee K. Synth. Commun. 2014; 44: 1924
• 8 Justaud F, Hachem A, Grée R. Eur. J. Org. Chem. 2021; 514
• 9 Antiñolo A, Carrillo-Hermosilla F, Cadierno V, García-Álvarez J, Otero A. ChemCatChem 2012; 4: 123
• 10 Picquet M, Bruneau C, Dixneuf PH. Chem. Commun. 1997; 1201
• 11 Suzuki T, Tokunaga M, Wakatsuki Y. Tetrahedron Lett. 2002; 43: 7531
• 12 Cadierno V, García-Garrido SE, Gimeno J, Nebra N. Inorg. Chim. Acta 2010; 363: 1912
• 13 Cadierno V, García-Garrido SE, Gimeno J. Adv. Synth. Catal. 2006; 348: 101
• 14 Cadierno V, Gimeno J. Chem. Rev. 2009; 109: 3512
• 15 Bauer EB. Synthesis 2012; 44: 1131
• 16 Dudley GB, Engel DA, Lopez SS. Synlett 2007; 949
• 17 Engel DA, Dudley GB. Org. Lett. 2006; 8: 4027
• 18 García-Álvarez J, Díez J, Vidal C, Vicent C. Inorg. Chem. 2013; 52: 6533
• 19 Kim SM, Lee D, Hong SH. Org. Lett. 2014; 16: 6168
• 20 Pennell MN, Kyle MP, Gibson SM, Male L, Turner PG, Grainger RS, Sheppard TD. Adv. Synth. Catal. 2016; 358: 1519
• 21 Pennell MN, Turner PG, Sheppard TD. Chem. Eur. J. 2012; 18: 4748
• 22 Pennell MN, Unthank MG, Turner P, Sheppard TD. J. Org. Chem. 2011; 76: 1479
• 23 Ramón RS, Gaillard S, Slawin AM. Z, Porta A, D’Alfonso A, Zanoni G, Nolan SP. Organometallics 2010; 29: 3665
• 24 Hatzfeld J, Skowaisa S, Jäckel E, Kaufmann J, Haak E. Chem. Eur. J. 2021; 27: 15545
• 25 Kaufmann J, Jäckel E, Haak E. ARKIVOC 2019; 91
• 26 Kaufmann J, Jäckel E, Haak E. Angew. Chem. Int. Ed. 2018; 57: 5908 ; Angew. Chem. 2018, 130, 6010
• 27 Jonek A, Berger S, Haak E. Chem. Eur. J. 2012; 18: 15504
• 28 Thies N, Hrib CG, Haak E. Chem. Eur. J. 2012; 18: 6302
• 29 Preparation of Meyer–Schuster Products 5; General Procedure: The catalyst 1 (20 mg, 0.04 mmol, 4 mol%), NaHSO₄ (240 mg, 2 mmol, 2 equiv), and the propargyl alcohol (1 mmol, 1 equiv) were dissolved in CDCl₃ (2 mL). The mixture was heated under microwave irradiation (120 °C, 0.5–1 h). Mesitylene was added as an internal standard and the yield was determined using NMR spectroscopy. For unknown compounds, the solvent was removed under reduced pressure and the crude product was purified by flash chromatography on silica (gradient: pentane/diethyl ether). Selected examples (see the Supporting Information for full characterization data):(E)-Oct-2-enal (5c): C₈H₁₄O. ¹H NMR (400 MHz, CDCl₃): δ = 9.49 (d, J = 7.9 Hz, 1 H, 1-H), 6.84 (dt, J = 6.8, 15.6 Hz, 1 H, 3-H), 6.11 (ddt, J = 1.5, 7.9, 15.6 Hz, 1 H, 2-H), 2.32 (ddt, J = 1.5, 7.1, 7.9 Hz, 2 H, 4-H), 1.51 (quint, J = 7.2 Hz, 2 H, 6-H), 1.36–1.26 (m, 4 H, 5-H, 7-H), 0.90 (t, J = 7.1 Hz, 3 H, 8-H). ¹³C NMR (100 MHz, CDCl₃): δ = 194.2 (1-C), 159.1 (3-C), 133.1 (2-C), 32.8 (4-C), 31.4 (6-C), 27.6 (5-C), 22.5 (7-C), 14.0 (8-C). HRMS (ESI): m/z [M + H]⁺ calcd for C₈H₁₅O: 127.1118; found: 127.1129.(E)-Non-3-en-2-one (5p): C₉H₁₆O. ¹H NMR (400 MHz, CDCl₃): δ = 6.79 (dt, J = 6.9, 15.9 Hz, 1 H, 4-H), 6.06 (dt, J = 1.6, 16.0 Hz, 1 H, 3-H), 2.58 (ddt, J = 1.3, 4.2, 7.8 Hz, 2 H, 5-H), 2.19 (s, 3 H, 1-H), 1.48–1.38 (m, 2 H, 7-H), 1.34–1.27 (m, 4 H, 6-H, 8-H), 0.89 (t, J = 6.6 Hz, 3 H, 9-H). ¹³C NMR (100 MHz, CDCl₃): δ = 199.4 (2-H), 148.9 (4-C), 131.4 (3-C), 32.5 (5-C), 31.6 (7-C), 29.4 (6-C), 27.9 (1-C), 22.5 (8-C), 14.1 (9-C). HRMS (ESI): m/z [M + H]⁺ calcd for C₉H₁₆O: 141.1274; found: 141.1291.
• 30 Preparation of Unsaturated Nitriles 8; General Procedure: The catalyst 1 (20 mg, 0.04 mmol, 4 mol%), hydroxylamine-O-sulfonic acid (226 mg, 2 mmol, 2 equiv), anhydrous Na₂SO₄ (284 mg, 2 mmol, 2 equiv), and the propargyl alcohol (1 mmol, 1 equiv) were dissolved in C₆D₆ (2 mL). The mixture was heated at reflux by conventional heating (90 °C, 4 h). Mesitylene was added as an internal standard and the yield was determined using NMR spectroscopy. For unknown compounds, the solvent was removed under reduced pressure and the crude product was purified by flash chromatography on silica (gradient: pentane/diethyl ether). Selected example (see the Supporting Information for full characterization data): (E)-4-Ethyloct-2-enenitrile (8e) C₁₀H₁₇N. ¹H NMR (400 MHz, CDCl₃): δ = 6.48 (dd, J = 9.2, 16.4 Hz, 1 H, 3-H), 5.27 (dd, J = 0.9, 16.4 Hz, 1 H, 2-H), 2.08–1.99 (m, 1 H, 4-H), 1.64–1.55 (m, 1 H, 9-H), 1.47–1.41 (m, 1 H, 5-H), 1.34–1.18 (m, 6 H, 5-H, 6-H, 7-H, 9-H), 0.89 (t, J = 7.4 Hz, 3 H, 8-H), 0.84 (t, J = 7.6 Hz, 3 H, 10-H). ¹³C NMR (100 MHz, CDCl₃): δ = 160.5 (3-C), 117.7 (1-C), 99.5 (2-C), 45.8 (4-C), 34.3 (5-C), 29.4 (6-C), 27.0 (9-C), 22.5 (7-C), 14.2 (8-C), 11.6 (10-C). HRMS (ESI): m/z [M + H]⁺ calcd for C₁₀H₁₈N: 152.1434; found: 152.1431.
• 31 Fizet C, Streith J. Tetrahedron Lett. 1974; 3187