A Simple Way to Some Sophisticated Fused Nitrogen Heterocycles

Abstract

Selected nitroarenes were found to react with arylmethylene compounds prone to form benzylic-type carbanion to give fused nitrogen heterocycles in the presence of silylating agent.

Key words

nitroarenes - cyclizations - heterocycles - carbanions - nucleophilic aromatic substitution

References

• 1 Wróbel Z. Tetrahedron Lett.  1997,  38:  4913 
• 2 Wróbel Z. Tetrahedron  1998,  54:  2606 
• 3 Wróbel Z. Eur. J. Org. Chem.  2000,  521 
• 4 Curtin DY. Dybrig DH. J. Am. Chem. Soc.  1962,  84:  225 
• 5 Wróbel Z. Synlett  2001,  1927 
• 7 Allais A, and Poittevin A. inventors; Ger. Pat.  2026080.  ; Chem. Abstr. 1971, 74, 53577

6

Selected analytical data (¹H NMR: 400 MHz, DMSO-d ₆, δ in ppm, J in Hz; HRMS 70 eV). Compound 3a: ¹H NMR: δ = 7.95-8.00 (m, 1 H), 8.04 (dd, J = 9.4, 2.2, 1 H), 8.05-8.09 (m, 1 H), 8.28 (dd, J = 2.2, 0.4, 1 H), 8.32-8.36 (m, 2 H), 8.37 (dd, J = 9.4, 0.4, 1 H). HRMS: m/z calcd for C₁₄H₇N₂Cl: 238.0298; found: 238.031. Mp 204-207 °C (lit.⁷ mp 208 °C). Compound 3b: δ = 7.07 (ddd, J = 8.6, 6.7, 1.2, 1 H), 8.07 (ddd, J = 8.8, 6.7, 1.5, 1 H), 8.13 (dd, J = 9.3, 2.1, 1 H), 8.28 (dd, J = 9.3, 0.6, 1 H), 8.31-8.35 (m, 2 H), 8.43 (dd, J = 2.1, 0.6, 1 H). HRMS: m/z calcd for C₁₄H₇N₂ ⁷⁹Br: 281.979; found: 281.980. Compound 3c: δ = 2.36 (s, 3 H), 3.92 (s, 3 H), 7.43 (d, J = 9.2, 1 H), 7.40 (AA′part, 2 H), 7.79 (d, J = 5.9, 1 H), 7.93 (XX′ part, 2 H), 8.43 (d, J = 9.2, 1 H), 8.49 (d, J = 5.9, 1 H). HRMS: m/z calcd for C₁₈H₁₄N₂S₂O₃: 370.0446; found: 370.0440. Compound 3d: δ = 2.32 (s, 3 H), 4.10 (s, 3 H), 7.44 (AA′ part, 2 H), 7.81-7.88 (m, 3 H), 7.85 (s, 1 H), 7.86 (d, J = 5.7, 1 H), 7.97 (XX′ part, 2 H), 8.22-8.25 (m, 1 H), 8.45 (d, J = 5.7, 1 H). HRMS: m/z calcd for C₂₃H₁₇NS₂O₃: 419.0650; found: 419.0645. Compound 3f: δ = 2.36 (s, 3 H), 4.24 (s, 3 H), 7.26-7.28 (m, 2 H), 7.72 (dd, J = 8.3, 4.4, 1 H), 7.76 (d, J = 5.8, 1 H), 7.95-7.97 (m, 2 H), 8.02 (d, J = 5.8, 1 H), 8.27 (s, 1 H), 9.12 (dd, J = 4.4, 1.8, 1 H), 9.67 (dd, J = 8.3, 1.8, 1 H). HRMS: m/z calcd for C₂₂H₁₆N₂S₂O₃: 420.0602; found: 420.0587. Compound 3g: δ = 2.37 (s, 3 H), 7.29-7.35 (m, 4 H), 7.60-7.64 (m, 2 H), 7.71 (ddd, J = 8.2, 7.1, 1.5, 1 H), 7.78 (ddd, J = 8.2, 7.1, 1.5, 1 H), 7.83 (d, J = 5.8, 1 H), 8.08-8.12 (m, 2 H), 8.15 (ddd, J = 8.2, 1.5, 0.5, 1 H), 8.20 (d, J = 5.8, 1 H), 9.46 (ddd, J = 8.2, 1.5, 0.5, 1 H), 9.60 (s, 1 H). MS: 563 [M⁺]. Compound 3h: δ = 2.29 (s, 3 H), 7.06-7.11 (m, 2 H), 7.36 (dd, J = 8.5, 4.4, 1 H), 7.50-7.55 (m, 2 H), 7.76 (d, J = 5.8, 1 H), 8.10 (d, J = 8.10, 1 H), 8.14 (d, J = 9.4, 1 H), 8.2 (d, J = 9.4, 1 H), 8.86 (dd, J = 4.4, 1.4, 1 H), 9.57 (dd, J = 8.5, 1.4, 1 H). HRMS: m/z calcd for C₂₁H₁₄N₂S₂O₂: 390.0497; found: 390.0493. Compound 4e: δ = 7.24 (dd, J = 5.0, 3.7, 1 H), 7.27 (d, J = 9.2, 1 H), 7.57 (dd, J = 8.0, 4.5, 1 H), 7.60 (dd, J = 5.0, 1.1, 1 H), 7.64 (d, J = 9.2, 1 H), 7.81 (dd, J = 3.7, 1.1, 1 H), 8.05 (dd, J = 8.0, 1.6, 1 H), 8.94 (dd, J = 4.5, 1.6, 1 H). Compound 4f: δ = 4.15 (s, 3 H), 6.93 (s, 1 H), 7.26 (dd, J = 5.1, 3.7, 1 H), 7.58 (dd, J = 5.1, 1.1, 1 H), 7.60 (dd, J = 8.0, 4.5, 1 H), 7.73 (dd, J = 3.7, 1.1, 1 H), 8.82 (dd, J = 8.0, 1.8, 1 H), 9.05 (dd, J = 4.5, 1.8, 1 H). Compound 4g: 7.30 (dd, J = 5.1, 3.8, 1 H), 7.38-7.42 (m, 2 H), 7.65-7.70 (m, 3 H), 7.88-7.92 (m, 1 H), 7.93 (dd, J = 3.8, 1.2, 1 H), 8.46 (s, 1 H), 8.56-8.59 (m, 1 H). MS: 425 [M⁺].