One-Pot Synthesis of Cyclic Carbonates from Aldehydes, Sulfur Ylide, and CO₂

Abstract

Treatment of aldehydes with sulfur ylide (CH₂=SOMe₂ or CH₂=SMe₂), in the presence of CO₂ (1 atm) bubbled sequentially under mild conditions, produces cyclic carbonates in preparative yields. Sodium iodide formed in situ promotes the reaction between epoxide as intermediate and CO₂ at ambient conditions, thus constituting a powerful metal-free synthesis of organic cyclic carbonates directly from aldehydes.

Key words

cyclization - epoxides - insertion - carbon dioxide - cyclic carbonates

• References and Notes

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• 16 General Description Solvents were purified and dried by standard procedures before use; PE of boiling range 60–80 °C was used. Melting points are uncorrected and recorded on a Buchi B-542 instrument. ¹H NMR and ¹³C NMR spectra were recorded on Bruker AC-200 spectrometer unless mentioned otherwise. Elemental analysis was carried out on a Carlo Erba CHNS-O analyzer. Infrared spectra were recorded on Shimadzu FTIR-8400 spectrometer and absorption is expressed in cm^–1. HRMS data for new compounds were recorded on a Thermo Scientific Q-Exactive, Accela 1250 pump. Purification was done using column chromatography (230–400 mesh). General Experimental Procedure for the Preparation of Cyclic Carbonates 4a–v NaH (0.132 g, 3.3 mmol; previously washed with anhydrous PE to remove oil) was taken in an oven-dried three-necked flask, followed by addition of anhydrous DMSO (10 mL) through a septum to it, and the whole slurry was stirred at 25 °C under N₂ atmosphere. Solid Me₃SOI (0.726 g, 3.3 mmol) was added to the slurry with stirring over a period of 5 min via a solid addition funnel until it becomes a homogeneous solution. A solution of aldehyde 1a–v (3 mmol), dissolved in anhydrous THF (10 mL), was added dropwise to the reaction mixture. After 1 h, CO₂ (1 atm) was then bubbled slowly via a needle into the reaction mixture, (after ascertaining that aldehyde was completely converted into epoxide, monitored by TLC) at 40 °C, for 6 h. Water (10 mL) was added to quench the reaction. It was then extracted with EtOAc (3 × 20 mL); the organic layer was washed with brine and dried over anhydrous Na₂SO₄ and the solvent concentrated, product purified by silica gel column chromatography (100–200 mesh) using PE and EtOAc (70:30) as eluent to afford pure cyclic carbonates 4a–v. 4-Phenyl-1,3-dioxolan-2-one (4a) Yield 94% (463 mg, 2.82 mmol); colorless solid; mp 53–54 °C (lit. mp 51–53 °C). IR (CHCl₃): ν_max = 769, 1068, 1168, 1328, 1458, 1812 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 4.29 (t, J = 7.9 Hz, 1 H), 4.77 (t, J = 7.9 Hz, 1 H), 5.64 (t, J = 7.9 Hz, 1 H), 7.32–7.42 (m, 5 H). ¹³C NMR (50 MHz, CDCl₃): δ = 70.9, 77.8, 125.7, 129.0, 129.4, 135.8, 154.6. Anal. Calcd (%) for C₉H₈O₃: C, 65.85; H, 4.91. Found: C, 65.84; H, 4.90. 4-Methyl-1,3-dioxolan-2-one (4b) Yield 40% (122.5 mg, 1.2 mmol); colorless oil; IR (CHCl₃): ν_max = 711, 776, 1051, 1120, 1183, 1354, 1389, 1793 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 1.49 (d, J = 6.1 Hz, 3 H), 4.02 (dd, J = 8.2, 1.0 Hz, 1 H), 4.55 (t, J = 8.0 Hz, 1 H), 4.77–4.94 (m, 1 H). ¹³C NMR (100 MHz, CDCl₃): δ = 19.0, 70.4, 73.4, 154.8. Anal. Calcd (%) for C₄H₆O₃: C, 47.06; H, 5.92. Found: C, 47.04; H, 5.91. 4-Ethyl-1,3-dioxolan-2-one (4c) Yield 65% (226.4 mg, 1.95 mmol); colorless oil. IR (CHCl₃): ν_max = 1060, 1177, 1377, 1797 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 1.03 (t, J = 7.4 Hz, 3 H), 1.72–1.87 (m, 2 H), 4.1 (dd, J = 8.2, 1.5 Hz, 1 H), 4.55 (t, J = 8.2 Hz, 1 H), 4.63–4.73 (m, 1 H). ¹³C NMR (50 MHz, CDCl₃): δ = 7.9, 26.2, 68.5, 77.6, 154.6. Anal. Calcd (%) for C₅H₈O₃: C, 51.72; H, 6.94. Found: C, 51.75; H, 6.91. 4-Isopropyl-1,3-dioxolan-2-one (4d) Yield 73% (285 mg, 2.19 mmol); colorless oil. IR (CHCl₃): ν_max = 1075, 1175, 1392, 1789 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 0.95 (d, J = 6.8 Hz, 3 H), 1.04 (d, J = 6.5 Hz, 3 H), 1.90–2.00 (m, 1 H), 4.12–4.18 (m, 1 H), 4.37–4.53 (m, 2 H). ¹³C NMR (50 MHz, CDCl₃): δ = 16.4, 16.8, 31.4, 67.2, 80.9, 154.6. HRMS (ESI⁺): m/z = calcd for (C₆H₁₀O₃)⁺ [M + H]⁺: 131.0709; found: 131.0708. Anal. Calcd (%) for C₆H₁₀O₃: C, 55.37; H, 7.75. Found: C, 55.40; H, 7.71. 4-Butyl-1,3-dioxolan-2-one (4e) Yield 89% (384.9 mg, 2.6 mmol); gum. IR (CHCl₃): ν_max = 1066, 1173, 1797 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 0.88–0.95 (m, 3 H), 1.23–1.40 (m, 3 H), 1.68–1.80 (m, 3 H), 4.05 (dd, J = 8.2, 1.0 Hz, 1 H), 4.51 (t, J = 8.2 Hz, 1 H), 4.62–4.76 (m, 1 H). ¹³C NMR (50 MHz, CDCl₃): δ = 13.8, 22.2, 26.4, 33.6, 69.3, 76.9, 154.9. Anal. Calcd (%) for C₇H₁₂O₃: C, 58.32; H, 8.39. Found: C, 58.34; H, 8.38%. 4-Hexyl-1,3-dioxolan-2-one (4f) Yield 94% (486 mg, 2.82 mmol); gum. IR (CHCl₃): ν_max = 772, 1065, 1170, 1802 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 0.86–0.93 (m, 3 H), 1.30–1.49 (m, 8 H), 1.69–1.80 (m, 2 H), 4.06 (t, J = 7.2 Hz, 1 H), 4.51 (t, J = 8.0 Hz, 1 H), 4.62–4.76 (m, 1 H). ¹³C NMR (50 MHz, CDCl₃): δ = 13.9, 22.4, 24.3, 28.7, 31.4, 33.8, 69.2, 76.8, 154.8. Anal. Calcd (%) for C₉H₁₆O₃: C, 62.77; H, 9.36. Found: C, 62.73; H, 9.40. 4-Vinyl-1,3-dioxolan-2-one (4g) Yield 65% (222.5 mg, 1.95 mmol); yellow oil. IR (CHCl₃): ν_max = 772, 991, 1060, 1168, 1385, 1510, 1805 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 4.17 (t, J = 7.8 Hz, 1 H), 4.61 (t, J = 8.4 Hz, 1 H), 5.12 (dd, J = 14.9, 7.5 Hz, 1 H), 5.48 (t, J = 16.5 Hz, 2 H), 5.83–6.0 (m, 1 H). ¹³C NMR (50 MHz, CDCl₃): δ = 68.8, 76.8, 120.9, 132.2, 154.2. HRMS (ESI⁺): m/z calcd for (C₅H₆O₃)⁺ [M + H]⁺: 115.0396; found: 115.0392; Anal. Calcd (%) for C₅H₆O₃: C, 52.63; H, 5.30. Found: C, 52.61; H, 5.32. (E)-4-Styryl-1,3-dioxolan-2-one (4h) Yield 98% (559 mg, 2.94 mmol); colorless solid; mp 115–116 °C. IR (CHCl₃): ν_max = 1049, 1070, 1168, 1648, 1800 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 4.23 (t, J = 8.0 Hz, 1 H), 4.64 (t, J = 8.2 Hz, 1 H), 5.26 (q, J = 7.9 Hz, 1 H), 6.15 (dd, J = 15.7, 7.7 Hz, 1 H), 6.73 (d, J = 15.7 Hz, 1 H), 7.26–7.40 (m, 5 H). ¹³C NMR (50 MHz, CDCl₃): δ = 69.2, 77.6, 122.4, 126.9, 128.8, 129.0, 134.8, 136.6, 154.4. HRMS (ESI⁺): m/z calcd for (C₁₁H₁₀O₃)⁺ [M + Na]⁺: 213.0527; found: 213.0522. Anal. Calcd (%) for C₁₁H₁₀O₃: C, 69.46; H, 5.30. Found: C, 69.41; H, 5.33. 4-(2-Methoxyphenyl)-1,3-dioxolan-2-one (4i) Yield 85% (495 mg, 2.55 mmol); gum. IR (CHCl₃): ν_max = 757, 1076, 1166, 1249, 1494, 1812 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 3.86 (s, 3 H), 4.25 (dd, J = 8.4, 1.1 Hz, 1 H), 4.82 (t, J = 8.4 Hz, 1 H), 5.81 (t, J = 8.0 Hz, 1 H), 6.90–7.04 (m, 2 H), 7.32–7.38 (m, 2 H). ¹³C NMR (50 MHz, CDCl₃): δ = 55.4, 70.5, 74.7, 110.5, 120.9, 124.9, 126.1, 130.3, 154.9, 156.1. Anal. Calcd (%) for C₁₀H₁₀O₄: C, 61.85; H, 5.19. Found: C, 61.79; H, 5.14. 4-(3,4,5-Trimethoxyphenyl)-1,3-dioxolan-2-one (4j) Yield 90% (686 mg, 2.7 mmol); brown solid; mp 133–134 °C. IR (CHCl₃): ν_max = 1068, 1125, 1243, 1510, 1796 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 3.84 (s, 3 H), 3.88 (s, 6 H), 4.31 (t, J = 8.3 Hz, 1 H), 4.78 (t, J = 8.4 Hz, 1 H), 5.60 (t, J = 7.9 Hz, 1 H), 6.54 (s, 2 H). ¹³C NMR (50 MHz, CDCl₃): δ = 56.1, 60.7, 71.1, 78.0, 102.6, 131.2, 138.8, 153.8, 154.5. HRMS (ESI⁺): m/z calcd for (C₁₂H₁₄O₆)⁺ [M + H]⁺: 255.0869; found: 255.0855. Anal. Calcd (%) for C₁₂H₁₄O₆: C, 56.69; H, 5.55. Found: C, 56.62; H, 5.50. 4-(4-Fluorophenyl)-1,3-dioxolan-2-one (4k) Yield 90% (492 mg, 2.7 mmol); colorless solid; mp 91–92 °C. IR (CHCl₃): ν_max = 773, 840, 1069, 1161, 1210, 1385, 1514, 1818 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 4.31 (t, J = 8.2 Hz, 1 H), 4.80 (t, J = 8.3 Hz, 1 H), 5.66 (t, J = 8.0 Hz, 1 H), 7.08–7.19 (m, 2 H), 7.32–7.40 (m, 2 H). ¹³C NMR (50 MHz, CDCl₃): δ = 71.0, 77.3, 116, 116.5, 127.9, 128.0, 131.6, 154.4, 160.84, 165.8. Anal. Calcd (%) for C₉H₇FO₃: C, 59.35; H, 3.87. Found: C, 59.37; H, 3.86. 4-(4-Chlorophenyl)-1,3-dioxolan-2-one (4l) Yield 87% (518 mg, 2.61 mmol); colorless solid; mp 70–71 °C (lit. mp 68–69 °C). IR (CHCl₃): ν_max = 770, 829, 1071, 1167, 1384, 1494, 1816 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 4.29 (t, J = 8.4 Hz, 1 H), 4.80 (t, J = 8.4 Hz, 1 H), 5.65 (t, J = 7.8 Hz, 1 H), 7.28–7.33 (m, 2 H), 7.36–7.44 (m, 2 H). ¹³C NMR (50 MHz, CDCl₃): δ = 70.9, 77.1, 127.2, 129.4, 134.4, 135.7, 154.3. Anal. Calcd (%) for C₉H₇ClO₃: C, 54.43; H, 3.55. Found: C, 54.37; H, 3.56. 4-(2-Bromophenyl)-1,3-dioxolan-2-one (4m) Yield 96% (700 mg, 2.88 mmol); gum. IR (CHCl₃): ν_max = 763, 969, 1072, 1125, 1159, 1208, 1473, 1817 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 4.24 (dd, J = 6.8, 1.7 Hz, 1 H), 4.99 (t, J = 8.4 Hz, 1 H), 5.94 (t, J = 8.0 Hz, 1 H), 7.28–7.39 (m, 1 H), 7.43–7.62 (m, 3 H). ¹³C NMR (50 MHz, CDCl₃): δ = 70.4, 76.3, 120.1, 126.0, 128.1, 130.4, 132.96, 136.3, 154.3. Anal. Calcd (%) for C₉H₇BrO₃: C, 44.47; H, 2.90. Found: C, 44.45; H, 2.86. 4-[4-(Trifluoromethyl)phenyl]-1,3-dioxolan-2-one (4n) Yield 98% (683 mg, 2.94 mmol); gum. IR (CHCl₃): ν_max = 771, 844, 1071, 1167, 1264, 1327, 1426, 1822 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 4.30 (t, J = 7.8 Hz, 1 H), 4.85 (t, J = 8.4 Hz, 1 H), 5.74 (t, J = 7.9 Hz, 1 H), 7.48 (d, J = 8.0 Hz, 1 H), 7.70–7.74 (d, J = 8.2 Hz, 2 H). ¹³C NMR (50 MHz, CDCl₃): δ = 70.8, 76.8, 126.0, 126.2, 126.3, 126.4, 139.9, 154.2. HRMS (ESI⁺): m/z calcd for (C₁₀H₇F₃O₃)⁺ [M + H]⁺: 233.0426; found: 233.0426. Anal. Calcd (%) for C₁₀H₇F₃O₃: C, 51.74; H, 3.04. Found: C, 51.71; H, 3.06. 4-(2-Nitrophenyl)-1,3-dioxolan-2-one (4o) Yield 79% (496 mg, 2.37 mmol); brown solid; mp 95–96 °C. IR (CHCl₃): ν_max = 1073, 1167, 1350, 1527, 1819 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 4.27 (dd, J = 9.0, 3.3 Hz, 1 H), 5.17 (t, J = 8.9 Hz, 1 H), 6.28 (dd, J = 8.7, 2.7 Hz, 1 H), 7.60–7.68 (m, 1 H), 7.83 (d, J = 4.0 Hz, 2 H), 8.26 (d, J = 8.2 Hz, 1 H). ¹³C NMR (50 MHz, CDCl₃): δ = 71.2, 74.3, 125.6, 126.2, 129.9, 134.1, 135.1, 145.9, 154.2 Anal. Calcd (%) for C₉H₇NO₅: C, 51.68; H, 3.37; N, 6.70. Found: C, 51.71; H, 3.35; N, 6.66. 4-(3-Nitrophenyl)-1,3-dioxolan-2-one (4p) Yield 75% (470 mg, 2.25 mmol); brown solid; mp 97–98 °C. IR (CHCl₃): ν_max = 1071, 1166, 1349, 1530, 1805 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 4.35 (dd, J = 8.7, 1.1 Hz, 1 H), 4.91 (t, J = 8.5 Hz, 1 H), 5.81 (t, J = 7.8 Hz, 1 H), 7.64–7.78 (m, 2 H), 8.24–8.33 (m,2 H). ¹³C NMR (50 MHz, CDCl₃): δ = 70.7, 76.3, 120.9, 124.5, 130.5, 131.4, 138.2, 148.6, 153.8. HRMS (ESI⁺): m/z calcd for (C₉H₇NO₅)⁺ [M + Na]⁺: 232.0221; found: 232.0214. Anal. Calcd (%) for C₉H₇NO₅: C, 51.68; H, 3.37; N, 6.70. Found: C, 51.72; H, 3.34; N, 6.68. 4-{Benzo[d][1,3]dioxol-5-yl}-1,3-dioxolan-2-one (4q) Yield 86% (537 mg, 2.58 mmol); gum. IR (CHCl₃): ν_max = 1070, 1164, 1251, 1505, 1791 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 4.32 (t, J = 8.4 Hz, 1 H), 4.75 (t, J = 8.5 Hz, 1 H), 5.58 (t, J = 8.0 Hz, 1 H), 6.01 (s, 2 H), 6.84 (s, 3 H). ¹³C NMR (50 MHz, CDCl₃): δ = 71.0, 78.0, 101.5, 106.1, 108.6, 120.3, 129.2, 148.5, 148.8, 154.6. Anal. Calcd (%) for C₁₀H₈O₅: C, 57.70; H, 3.87. Found: C, 57.72; H, 3.84. 4-[2-(Benzyloxy)ethyl]-1,3-dioxolan-2-one (4r) Yield 80% (533 mg, 2.4 mmol); gum. IR (CHCl₃): ν_max = 1061, 1173, 1364, 1454, 1794 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 2.02–2.10 (m, 2 H), 3.58–3.65 (m, 2 H), 4.17 (dd, J = 8.4, 1.0 Hz, 1 H), 4.47–4.52 (m, 3 H), 4.79–4.93 (m, 1 H), 7.29–7.40 (m, 5 H). ¹³C NMR (50 MHz, CDCl₃): δ = 32.0, 33.9, 61.5, 65.3, 69.1, 69.6, 73.1, 73.3, 75.0, 127.5, 127.8, 128.3, 128.4, 137.5, 154.7. Anal. Calcd (%) for C₁₂H₁₄O₄: C, 64.85; H, 6.35. Found: C, 64.82; H, 6.31. 4-Phenethyl-1,3-dioxolan-2-one (4s) Yield 77% (444 mg, 2.31 mmol); gum. IR (CHCl₃): ν_max = 1061, 1165, 1796 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 1.94–2.17 (m, 2 H), 2.72–2.91 (m, 2 H), 4.01 (dd, J = 8.3, 1.1 Hz, 1 H), 4.44 (t, J = 8.2 Hz, 1 H), 4.62–4.68 (m, 1 H), 7.15–7.34 (m, 5 H). ¹³C NMR (50 MHz, CDCl₃): δ = 30.8, 35.6, 69.1, 75.8, 126.5, 128.3, 128.7, 139.6, 154.6. Anal. Calcd (%) for C₁₁H₁₂O₃: C, 68.74; H, 6.29. Found: C, 68.71; H, 6.26. 4,5-Dimethoxy-2-(2-oxo-1,3-dioxolan-4-yl)benzonitrile (4t) Yield 83% (690.42, 2.49 mmol); gum. IR (CHCl₃): ν_max = 1064, 1168, 1270, 1516, 1793, 2218 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 2.09 (q, J = 7.8 Hz, 1 H), 2.89–2.98 (m, 1 H), 3.89 (s, 3 H), 3.94 (s, 3 H), 4.14 (dd, J = 8.3, 1.6 Hz, 1 H), 4.54 (t, J = 8.2 Hz, 1 H), 4.62–4.73 (m, 1 H), 6.80 (s, 1 H), 7.03 (s, 1 H). ¹³C NMR (50 MHz, CDCl₃): δ = 29.5, 35.0, 56.1, 69.0, 75.6, 103.0, 112.3, 114.2, 118.0, 138.1, 147.9, 152.9, 154.5. HRMS (ESI⁺): m/z calcd for (C₁₄H₁₅NO₅)⁺ [M + H]⁺: 278.1023; found: 278.1026. Anal. Calcd (%) for C₁₄H₁₅NO₅ C, 60.64; H, 5.45; N, 5.05. Found: C, 60.60; H, 5.40; N, 5.10. tert-Butyl {(S)-1-[(S)-2-Oxo-1,3-dioxolan-4-yl]-2-phenylethyl}carbamate (4u) Yield 79% (728 mg, 2.37 mmol); colorless solid; mp 148–149 °C. IR (CHCl₃): ν_max = 1061, 1169, 1249, 1366, 1689, 1800 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 1.40 (s, 9 H), 2.82–2.89 (m, 2 H), 4.09 (m, 1 H), 4.28–4.44 (m, 2 H), 4.67 (m, 2 H), 7.22–7.33 (m, 5 H). ¹³C NMR (50 MHz, CDCl₃): δ = 28.2, 38.5, 52.8, 66.5, 76.1, 80.4, 127.1, 128.88, 129.2, 136.4, 154.6, 155.9. Anal. Calcd (%) for C₁₆H₂₁NO₅: C, 62.53; H, 6.89; N, 4.56. Found: C, 62.57; H, 6.91; N, 4.60. 4-[4-(Methylthio)phenyl]-1,3-dioxolan-2-one (4v) Yield 90% (573 mg, 2.73 mmol); yellow solid; mp 55–57 °C. IR (CHCl₃): ν_max = 817, 895, 1062, 1173, 1384, 1514, 1767 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 2.49 (s, 3 H), 4.30 (t, J = 8.1 Hz, 1 H), 4.76 (t, J = 8.2 Hz, 1 H), 5.61 (t, J = 8.0 Hz, 1 H), 7.27 (s, 4 H). ¹³C NMR (100 MHz, CDCl₃): δ = 15.0, 70.7, 77.5, 125.8, 131.9, 140.7, 154.5. Anal. Calcd (%) for C₁₀H₁₀SO₃: C, 57.13; H, 4.79. Found: C, 57.17; H, 4.86. HRMS (ESI⁺): m/z calcd for (C₁₀H₁₀O₃S)⁺ [M + H]⁺: 211.0429; found: 211.0441. 2-Iodo-1-phenylethan-1-ol (3a) Gum. IR (CHCl₃): ν_max = 699, 1054, 1174, 1452, 3404 cm^–1. ¹H NMR (200 MHz, CDCl₃): δ = 2.44 (br s, 1 H), 3.33–3.52 (m, 2 H), 4.80–4.84 (m, 1 H), 7.31–7.38 (m, 5 H). ¹³C NMR (50 MHz, CDCl₃): δ = 1502, 74.0, 125.7, 128.3, 128.6, 141.1. Anal. Calcd (%) for C₈H₉IO: C, 38.74; H, 3.66. Found: C, 38.70; H, 3.63.