Synlett 2007(7): 1031-1036  
DOI: 10.1055/s-2007-973891
LETTER
© Georg Thieme Verlag Stuttgart · New York

Sequential Alkylation/Heterocyclization of β-(2-Aminophenyl)-α,β-ynones Promoted by Electrogenerated Carbanions: A New Approach to ­Functionalized 4-Alkylquinolines

Antonio Arcadi*a, Gabriele Bianchia, Achille Inesib, Fabio Marinellia, Leucio Rossi*a
a Dipartimento di Chimica, Ingegneria Chimica e Materiali, Università degli Studi dell’Aquila, via Vetoio - Coppito due, 67010 L’Aquila, Italy
Fax: +(39)0862433753; e-Mail: arcadi@univaq.it; e-Mail: rossil@ing.univaq.it;
b Dipartimento di Ingegneria Chimica, Materie Prime, Metallurgia, Università ‘La Sapienza’, via del Castro Laurenziano 7, 00137 Roma, Italy
Further Information

Publication History

Received 30 January 2007
Publication Date:
13 April 2007 (online)

Abstract

Electrolysis in a divided cell (nitroalkanes or methanol, in the absence of solvent and supporting electrolyte, as catholite) gave functionalized 4-alkylquinolines in moderate to high yields through a sequential alkylative heterocyclization of β-(2-amino­phenyl)-α,β-ynones. The sequential alkylative heterocyclization process can be extended to the reaction of β-(2-aminophenyl)-α,β-ynones with 1,3-dicarbonyls by galvanostatic electrolysis of these latter derivatives in a tetraethylammonium tetrafluoroborate-N,N-dimethylformamide solution.

    References and Notes

  • 1 Bray PG. Ward SA. O" Neill PM. Curr. Top. Microbiol.  2005,  295:  3 
  • 2a Zouhiri F. Danet M. Bérnard C. Normand-Bayle M. Mouscadet JF. Leh H. Thomas CM. Mbemba G. d’Angelo J. Desmaële D. Tetrahedron Lett.  2005,  46:  2201 
  • 2b Normand-Bayle M. Bérnard C. Zouhiri F. Mouscadet JF. Leh H. Thomas CM. Mbemba G. Desmaële D. d’Angelo J. Bioorg. Med. Chem. Lett.  2005,  15:  4019 
  • 3 Narender P. Srinivas U. Ravinder M. Anada Rao B. Ramesh C. Harakishore K. Gangadasu B. Murthy USN. Jayathirtha Rao V. Bioorg. Med. Chem.  2006,  14:  4600 
  • 4 Rossiter S. Péron JM. Whitfield PJ. Jones K. Bioorg. Med. Chem. Lett.  2005,  15:  4806 
  • 5 Joshi AA. Viswanathan CL. Bioorg. Med. Chem. Lett.  2006,  16:  2613 
  • 6 Nayyar A. Malde A. Couthinho E. Jain R. Bioorg. Med. Chem.  2006,  14:  7302 
  • 7 Kiselyov AS. Piatnitsky E. Semenova M. Semenov VV. Bioorg. Med. Chem. Lett.  2006,  16:  602 
  • 8 Goodell JR. Puig-Basagoiti F. Forshey BM. Shi PY. Ferguson DM. J. Med. Chem.  2006,  49:  2127 
  • 9 Cappelli A. Pericot Mohr G. Gallelli A. Giuliani G. Anzini M. Vomero S. Fresta M. Porcu P. Maciocco E. Concas A. Biggio G. Donati A. J. Med. Chem.  2003,  46:  3568 
  • 10a Jiang J. Hoang M. Young JR. Chaung D. Eid R. Turner C. Lin P. Tong X. Wang J. Tan C. Feighner S. Palyha O. Hreniuk DL. Pan J. Sailer AW. MacNeil DJ. Howard A. Shearman L. Stribling S. Camacho R. Strack A. Van der Ploeg LHT. Goulet MT. DeVita J. Bioorg. Med. Chem. Lett.  2006,  16:  5270 
  • 10b Tavares FX. Al-Barazanji KA. Bigham EC. Bishop MJ. Britt CS. Carlton DL. Fedman PL. Goetz AS. Grizzle MK. Guo YC. Handlon AL. Hertzog DL. Ignar DM. Lang DG. Ott RJ. Peat J. Zhou H.-Q. J. Med. Chem.  2006,  49:  7905 
  • 11 Hu B. Collini M. Unwalla R. Miller C. Singhaus R. Quinte E. Savio D. Halpern A. Basso M. Keith J. Clerin V. Chen L. Resmini C. Liu Q.-Y. Feingold I. Huselton C. Azam F. Farnegardh M. Enroth C. Bonn T. Goos-Nilsson A. Wilhemsson A. Nambi P. Wrobel J. J. Med. Chem.  2006,  49:  6151 
  • 12a Tumambac GE. Rosencrance CM. Wolf C. Tetrahedron  2004,  60:  11293 
  • 12b Tong H. Wang L. Jing X. Wang F. Macromolecules  2003,  36:  2584 
  • Selected references:
  • 13a Li AH. Ahmed E. Chen X. Cox M. Crew AP. Dong HQ. Jin MZ. Ma LF. Panicker B. Siu KW. Steing AG. Stolz KM. Tavares PAR. Volk B. Weng QH. Werner D. Mulyihill M. Org. Biomol. Chem.  2007,  5:  61 
  • 13b Muscia GC. Bollini JP. Bruno AM. Asís SE. Tetrahedron Lett.  2006,  47:  8811 
  • 13c Varala R. Enugula R. Adapa SR. Synthesis  2006,  3825 
  • 13d Anguille S. Brunet JJ. Chu NC. Diallo O. Pages C. Vincendeau S. Organometallics  2006,  25:  2943 
  • 13e Ichikawa J. Sakoda K. Moriyama H. Wada Y. Synthesis  2006,  1590 
  • 13f Savitha G. Perumal PT. Tetrahedron Lett.  2006,  47:  3589 
  • 13g Kouznestov VV. Bohorquez ARR. Saavedra LA. Medina RF. Mol. Divers.  2006,  10:  29 
  • 13h Janza B. Studer A. Org. Lett.  2006,  8:  1875 
  • 13i Jia CS. Wang GW. Lett. Org. Chem.  2006,  3:  289 
  • 13j Lin XF. Cui SL. Wang YG. Tetrahedron Lett.  2006,  47:  3127 
  • 13k Sivaprasad G. Rajesh R. Perumal PT. Tetrahedron Lett.  2006,  47:  1783 
  • 13l Duggineni S. Sawant D. Saha B. Kundu B. Tetrahedron  2006,  62:  3228 
  • 13m Chaudhuri MK. Hussain S. J. Chem. Sci.  2006,  118:  199 
  • 14a Zolfigol MA. Salehi P. Ghaderi A. Shiri M. Tanbakouchian Z. J. Mol. Catal. A: Chem.  2006,  259:  253 
  • 14b Li YS. Wu CL. Huang JL. Su WK. Synth. Commun.  2006,  36:  3065 
  • 14c Selvam NP. Saravan C. Muralidharan D. Perumal PTJ. Heterocycl. Chem.  2006,  43:  1379 
  • 15a Abbiati G. Arcadi A. Canevari V. Capezzuto L. Rossi E. J. Org. Chem.  2005,  70:  6454 
  • 15b Rossi E. Abbiati G. Canevari V. Nava D. Arcadi A. Tetrahedron  2004,  60:  11391 
  • 15c Arcadi A. Marinelli F. Rossi E. Tetrahedron  1999,  55:  13233 
  • 16a Abbiati G. Arcadi A. Marinelli F. Rossi E. Eur. J. Org. Chem.  2003,  1423 
  • 16b Rossi E. Abbiati A. Arcadi A. Marinelli F. Tetrahedron Lett.  2001,  42:  3705 
  • 17 Abbiati G. Arcadi A. Marinelli F. Rossi E. Verdecchia M. Synlett  2006,  3218 
  • 18 Arcadi A. Chiarini M. Di Giuseppe S. Marinelli F. Synlett  2003,  203 
  • 19a Lund H. In Organic Electrochemistry   4th ed.:  Lund H. Hammerich O. Marcel Dekker; New York: 2001. 
  • 19b Bard AJ. Stratmann M. Encyclopedia of Electrochemistry, Organic Electrochemistry   Vol. 8:  Schäfer HJ. Wiley-VCH; Weinheim: 2004. 
  • 19c Torii S. Electroorganic Reduction Synthesis   Vol. 1 and 2:  Wiley-VCH; Koansha, Tokyo: 2006. 
  • 20 Caruso T. Feroci M. Inesi A. Orsini M. Scettri A. Palombi L. Adv. Synth. Catal.  2006,  348:  1942 
  • 21a Suba C. Murat E. Niyazymbetov E. Evans DH. Electrochim. Acta  1997,  42:  2247 
  • 21b Samet AV. Niyazymbetov ME. Semenov VV. Laikhter AL. Evans DH. J. Org. Chem.  1996,  61:  8786 
  • 21c Monte WT. Baizer MM. Little RD. J. Org. Chem.  1983,  48:  803 
  • 23 Nielsen AT. In The Chemistry of the Nitro and Nitroso Groups   Feuer H. Interscience; New York: 1970.  Part 2. p.372 
  • 25 Shankar R. Jha AK. Singh US. Hajela K. Tetrahedron Lett.  2006,  47:  3077 
22

β-(2-aminophenyl)-α,β-ynones 2a-d were prepared according to ref. 15c. General procedure for electrochemically promoted sequential alkylative cyclization reaction of nitroalkane 1a-c with β-(2-aminophenyl)-α,β-ynones 2: Pure nitroalkane, (2.0 mL) and TEATFB-DMF solution (0.1 M, 3.0 mL) were added to the cathodic and anodic compartment of the divided cell, respectively. The cell was equipped with a Pt mesh cathode (1.0 cm2) and a Pt spiral anode. The electrolysis was carried out under galvanostatic control (J = 30 mAcm-2, Q = 1.2 Fmol-1 referred to compound 2) at 0 °C. At the end of the electrolysis, the α,β-ynones 2 (0.2 mmol) were added to the cathode compartment and the reaction held at r.t. for the time reported in Table [1] . Once the TLC analysis showed the disappearance of 2, the excess of starting nitroalkane 1a-c was removed under vacuum and the residue purified by flash column chromatography to afford pure product 3a-j.
3b: pale yellow oil; 1H NMR (200 MHz, CDCl3): δ = 1.06 (t, J = 7.3 Hz, 3 H), 2.12-2.45 (m, 1 H), 2.34 (s, 6 H), 2.50-2.75 (m, 1 H), 6.22 (dd, J = 9.1, 5.6 Hz, 1 H), 7.05-7.15 (m, 2 H), 7.38 (d, J = 8.3 Hz, 1 H), 7.55-7.85 (m, 3 H), 8.06 (d, J = 8.1 Hz, 1 H), 8.21 (d, J = 7.9 Hz, 1 H); 13C NMR (50.3 MHz, CDCl3): δ = 10.9, 20.3, 21.2, 27.2, 87.3, 120.3, 121.8, 124.3, 125.4, 126.9, 127.6, 129.8, 130.0, 130.7, 131.8, 135.9, 138.9, 139.2, 148.4, 160.0; MS (EI): m/z (%) = 321 (13) [M + H]+, 275 (100).
3c: white solid; mp 84-86 °C; 1H NMR (200 MHz, CDCl3): δ = 1.04 (t, J = 7.3 Hz, 3 H), 2.10-2.35 (m, 1 H), 2.50-2.80 (m, 1 H), 3.79 (s, 3 H), 6.13-6.17 (m, 1 H), 6.96 (d, J = 8.8 Hz, 2 H, part of AA′BB′ system), 7.54 (t, J = 7.1 Hz, 1 H), 7.67 (t, J = 7.2 Hz, 1 H), 7.89 (s, 1 H), 8.05 (d, J = 8.8 Hz, 2 H, part of AA′BB′ system), 7.80-8.25 (m, 2 H); 13C NMR (50.3 MHz, CDCl3): δ = 10.9, 27.3, 55.4, 87.5, 114.4, 116.2, 121.8, 124.4, 125.0, 127.1, 129.0, 130.0, 130.6, 140.0, 148.6, 156.7, 161.3; MS (EI): m/z (%) = 322 (26) [M]+, 276 (100).
3d: pale brown solid; mp 110-112 °C; 1H NMR (200 MHz, CDCl3): δ = 1.05 (t, J = 7.3 Hz, 3 H), 2.12-2.32 (m, 1 H), 2.46-2.75 (m, 1 H), 3.81 (s, 3 H), 5.97 (dd, J = 8.8 Hz, 1 H), 6.93-7.05 (m, 2 H), 7.08-7.20 (m, 1 H), 7.32-7.47 (m, 2 H), 7.87 (dd, J = 7.6, 1.6 Hz, 1 H), 8.19 (s, 1 H); MS (EI): m/z (%) = 359 (25) [M + H]+, 312 (100).
3e: white solid; mp 127-129 °C; 1H NMR (200 MHz, CDCl3): δ = 2.32 (s, 3 H), 2.35 (s, 3 H), 5.90 (s, 2 H), 7.06 (s, 1 H), 7.09 (s, 1 H), 7.37 (d, J = 8.3 Hz, 1 H), 7.57 (s, 1 H), 7.60-7.75 (m, 1 H), 7.70-7.85 (m, 1 H), 7.96 (d, J = 8.3 Hz, 1 H), 8.15-8.35 (m, 1 H); 13C NMR (50.3 MHz, CDCl3): δ = 20.4, 21.2, 76.4, 122.4, 124.7, 125.1, 127.0, 128.0, 129.9, 130.2, 130.5, 131.9, 133.3, 136.1, 139.2, 159.4.
3f: white solid; mp 93-95 °C; 1H NMR (200 MHz, CDCl3): δ = 3.82 (s, 3 H), 5.90 (s, 2 H), 6.99 (d, J = 8.7 Hz, 2 H, part of AA′BB′), 7.50-7.65 (m, 1 H), 7.65-7.80 (m, 1 H), 7.83 (s, 1 H), 7.85-8.00 (m, 1 H), 8.08 (d, J = 8.7 Hz, 2 H, part of AA′BB′), 8.15-8.30 (m, 1 H).
3g: white solid; mp 53-55 °C; 1H NMR (200 MHz, CDCl3): δ = 2.09 (s, 6 H), 2.31 (s, 3 H), 2.35 (s, 3 H), 7.00-7.15 (m, 2 H), 7.30-7.75 (m, 5 H), 8.17 (d, J = 8.3 Hz, 1 H); 13C NMR (50.3 MHz, CDCl3): δ = 20.3, 21.2, 28.2, 89.4, 119.7, 122.7, 123.4, 126.9, 127.2, 129.4, 129.7, 131.2, 131.9, 136.0, 136.9, 138.9, 144.6, 148.7, 159.7; MS (EI): m/z (%) = 321 (6) [M + H]+, 274 (100).
3h: white solid; mp 107-109 °C; 1H NMR (200 MHz, CDCl3): δ = 2.12 (s, 6 H), 3.79 (s, 3 H), 6.96 (d, J = 8.8 Hz, 2 H, part of AA′BB′ system), 7.30-7.45 (m, 1 H), 7.45-7.70 (m, 2 H), 7.79 (s, 1 H), 8.04 (d, J = 8.8 Hz, 2 H, part of AA′BB′ system), 8.10-8.20 (m, 1 H); 13C NMR (50.3 MHz, CDCl3): δ = 28.1, 55.4, 89.6, 114.4, 115.9, 122.7, 123.5, 126.7, 128.9, 129.4, 131.1, 131.6, 145.1, 149.1, 156.4, 161.2; MS (EI): m/z (%) = 322 (5) [M]+, 276 (100).
3i: pale brown solid; mp 82-84 °C; 1H NMR (200 MHz, CDCl3): δ = 2.10 (s, 6 H), 3.83 (s, 3 H), 6.80-7.25 (m, 4 H), 7.30-7.50 (m, 1 H), 7.89 (dd, J = 7.6, 1.7 Hz, 1 H), 8.13 (s, 1 H); MS (EI): m/z (%) = 359 (10) [M + H]+, 312 (100).
3j: white solid; mp 196-198 °C; 1H NMR (200 MHz, CDCl3): δ = 2.20 (s, 6 H), 7.44-7.68 (m, 5 H), 7.66-7.86 (m, 3 H), 7.88-8.03 (m, 2 H), 8.05-8.15 (m, 1 H), 8.36 (d, J = 8.5 Hz, 1 H); 13C NMR (50.3 MHz, CDCl3): δ = 28.3, 89.5, 120.6, 122.8, 125.3, 125.4, 126.2, 127.0, 127.6, 128.1, 128.6, 129.7, 129.8, 130.3, 130.8, 131.3, 134.1, 137.2, 147.4, 158.9; MS (EI): m/z (%) = 341 (13) [M - H]+, 294 (100).

24

General procedure for electrochemically promoted reaction of dicarbonyl compound 1e-f to β-(2-aminophenyl)-α,β-ynones 2: A solution of dicarbonyl compound 1 (0.20 mmol) in TEATFB-DMF (0.1 M, 2 mL) and a solution of TEATFB-DMF (0.1 M, 3.0 mL) were added to the cathodic and anodic compartment of the divided cell, respectively. The cell was equipped with a Pt mesh cathode (1.0 cm2) and a Pt spiral anode. The electrolysis was carried-out under galvanostatic control (J = 30 mAcm-2, Q = 1.2 Fmol-1 referred to 2) at 0 °C. At the end of electrolysis the α,β-ynones 2 (0.2 mmol) were added to the cathode compartment and the reaction held at r.t. for the time reported in Table [1] . The mixture was then poured into NH4Cl sat. soln (50 mL) and extracted with Et2O (× 2). The organic layer, dried over Na2SO4, was evaporated in vacuo and the crude purified by flash column chromatography using hexane-Et2O mixtures to afford pure product 3.
3l: white solid; mp 180-182 °C; 1H NMR (200 MHz, CDCl3): δ = 3.73 (s, 6 H), 3.80 (s, 3 H), 5.40 (s, 1 H), 6.97 (d, J = 8.8 Hz, 2 H, part of AA′BB′ system), 7.40-7.60 (m, 1 H), 7.66 (t, J = 7.3 Hz, 1 H), 7.80-7.95 (m, 2 H), 8.07 (d, J = 8.8 Hz, 2 H, part of AA′BB′ system), 8.20 (d, J = 8.6 Hz, 1 H); 13C NMR (50.3 MHz, CDCl3): δ = 53.2, 53.4, 55.4, 114.3, 119.3, 122.4, 125.3, 126.7, 129.2, 129.8, 130.3, 131.2, 138.9, 148.4, 156.5, 161.2, 167.7; MS (EI): m/z (%) = 307 (100), 292 (35).
3m: white solid; mp 120-122 °C; 1H NMR (200 MHz, CDCl3): δ = 3.68 (s, 3 H), 3.74 (s, 3 H), 3.82 (s, 3 H), 5.20 (s, 1 H), 6.85-7.55 (m, 5 H), 7.87 (dd, J = 7.6, 1.5 Hz, 1 H), 8.10 (s, 1 H); MS (EI): m/z (%) = 251 (100), 208 (44).
3n: pale yellow oil; 1H NMR (200 MHz, CDCl3): δ = 1.00-1.35 (m, 3 H); 1.85-2.25 (m, 4 H), 2.35-2.55 (m, 2 H), 3.95-4.30 (m, 2 H), 7.20-8.05 (m, 11 H), 8.30 (d, J = 8.5 Hz, 1 H); MS (EI): m/z (%) = 409 (100) [M]+, 336 (26).