Synthesis 2022; 54(22): 5055-5063
DOI: 10.1055/s-0037-1610786
special topic
Aryne Chemistry in Synthesis

Regioselective Amination or Alkoxylation of Halogenated Amino-, Thio- or Alkoxypyridines via Pyridyne Intermediates

Benjamin Heinz
a   Ludwig-Maximilians-Universität München, Department Chemie, Butenandtstrasse 5–13, Haus F, 81377 München, Germany
,
Dimitrije Djukanovic
a   Ludwig-Maximilians-Universität München, Department Chemie, Butenandtstrasse 5–13, Haus F, 81377 München, Germany
,
Fiona Siemens
a   Ludwig-Maximilians-Universität München, Department Chemie, Butenandtstrasse 5–13, Haus F, 81377 München, Germany
,
Mohamed Idriess
a   Ludwig-Maximilians-Universität München, Department Chemie, Butenandtstrasse 5–13, Haus F, 81377 München, Germany
,
Benjamin Martin
b   Novartis Pharma AG, Chemical Development, Fabrikstraße, 4056 Basel, Switzerland
,
Paul Knochel
a   Ludwig-Maximilians-Universität München, Department Chemie, Butenandtstrasse 5–13, Haus F, 81377 München, Germany
› Author Affiliations
We thank the DFG and Novartis (Basel) for generous financial support.


Abstract

The treatment of 3-halopyridines (Cl, Br) bearing an R-substituent in position 2 (R = OEt, NEt2, N-piperidyl, or SEt) or in position 5 (R = OMe, OEt, SEt, NMe2, NEt2, or aryl) with KHMDS and an amine at 25 °C for 12 hours in THF provided regioselectively 3- and 4-aminated pyridines in 56–90% yields. The reaction of 3-bromo-2-diethylaminopyridine with various alcohols in the presence of t-BuOK/18-crown-6 in THF at 80 °C for 20–60 hours gave various 4-alkoxy-2-diethylaminopyridines in 61–81% yields. These substitution reactions were proposed to proceed via pyridyne intermediates.

Supporting Information



Publication History

Received: 15 September 2021

Accepted after revision: 29 September 2021

Article published online:
11 November 2021

© 2021. Thieme. All rights reserved

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 
  • References

    • 1a Eicher T, Hauptmann S, Speicher A. The Chemistry of Heterocycles, 2nd ed. Wiley-VCH; Weinheim: 2003
    • 1b Alvarez-Builla J, Vaquero JJ, Barluenga J. Modern Heterocyclic Chemistry,1st ed. Wiley-VCH; Weinheim: 2011
    • 2a Bisai V, Sarpong R. Org. Lett. 2010; 12: 2551
    • 2b Fischer DF, Sarpong R. J. Am. Chem. Soc. 2010; 132: 5926
    • 2c Newton JN, Fischer DF, Sarpong R. Angew. Chem. Int. Ed. 2013; 52: 1726
    • 2d Rouquet G, Blakemore DC, Ley SV. Chem. Commun. 2014; 50: 8908
    • 2e Rouquet G, Moore DE, Spain M, Allwood DM, Battilocchio C, Blakemore DC, Fish PV, Jenkinson S, Jessiman AS, Ley SV, McMurray G, Storer RA. ACS Med. Chem. Lett. 2015; 6: 329
    • 2f Xie L.-G, Shaaban S, Chen X, Maulide N. Angew. Chem. Int. Ed. 2016; 128: 13056
    • 2g Ekar J, Kranjc K. Synthesis 2021; 53: 1112
    • 2h Casadia I, Daher TO, Moura S, Back DF, Faoro E, Schwalm CS, Casagrande GA, Paveglio GC, Pizzuti L. Synthesis 2021; 53: 365
    • 2i Desaintjean A, Danton F, Knochel P. Synthesis 2021; 53: in press DOI: 10.1055/a-1551-4093.
    • 4a Comins DL, Killpack MO. J. Org. Chem. 1990; 55: 69
    • 4b Gros P, Fort Y, Queguiner G, Caubère P. Tetrahedron Lett. 1995; 36: 4791
    • 4c Choppin S, Gros P, Fort Y. Eur. J. Org. Chem. 2001; 603
    • 4d Balkenhohl M, François C, Roman DS, Quinio P, Knochel P. Org. Lett. 2017; 19: 536
    • 4e Balkenhohl M, Heinz B, Abegg T, Knochel P. Org. Lett. 2018; 20: 8057
    • 4f Bellan AB, Knochel P. Angew. Chem. Int. Ed. 2019; 58: 1838
    • 6a Mallet M, Quenguiner G. Tetrahedron 1982; 38: 3035
    • 6b Gribble GW, Saulnier MG. Heterocycles 1993; 35: 151
    • 6c Vinter-Pasquier K, Jamart-Gregoire B, Caubère P. Heterocycles 1997; 45: 2113
    • 6d Connon SJ, Hegarty AF. J. Chem. Soc., Perkin Trans. 1 2000; 1245
    • 6e Lin W, Chen L, Knochel P. Tetrahedron 2007; 63: 2787
    • 6f Cant AA, Bertrand GH. V, Henderson JL, Roberts L, Greaney MF. Angew. Chem. Int. Ed. 2009; 48: 5199

      For more recent contributions, see:
    • 7a Goetz AE, Bronner SM, Cisneros JD, Melamed JM, Paton RS, Houk KN, Garg NK. Angew. Chem. Int. Ed. 2012; 51: 2758
    • 7b Fang Y, Larock RC. Tetrahedron 2012; 68: 2819
    • 7c Goetz AE, Garg NK. Nat. Chem. 2013; 5: 54
    • 7d Goetz AE, Garg NK. J. Org. Chem. 2014; 79: 846
    • 7e Medina JM, Jackl MK, Susick RB, Garg NK. Tetrahedron 2016; 72: 3629
  • 8 Heinz B, Djukanovic D, Filipponi P, Martin B, Karaghiosoff K, Knochel P. Chem. Sci. 2021; 12: 6143
    • 9a Biehl ER, Smith SM, Reeves PC. J. Org. Chem. 1971; 36: 1841
    • 9b Xin HY, Biehl ER. J. Org. Chem. 1983; 48: 4397
    • 9c Biehl ER, Razzuk A, Jovanovic MV, Khanapure SP. J. Org. Chem. 1986; 51: 5157
    • 9d Razuk A, Biehl ER. J. Org. Chem. 1987; 52: 2619
    • 9e Lin W, Sapountzis I, Knochel P. Angew. Chem. Int. Ed. 2005; 44: 4258
    • 9f Medina JM, Mackey JL, Garg NK, Houk KN. J. Am. Chem. Soc. 2014; 136: 15798
    • 9g Nagaki A, Ichinari D, Yoshida J. J. Am. Chem. Soc. 2014; 136: 12245
    • 9h Garcia-Lopez J.-A, Cetin M, Greaney MF. Angew. Chem. Int. Ed. 2015; 54: 2156
    • 9i Garcia-Lopez J.-A, Cetin M, Greaney MF. Org. Lett. 2015; 17: 2649
    • 9j Ghorai S, Lee D. Synlett 2020; 31: 750
    • 9k Cho S, Wang Q. Org. Lett. 2020; 22: 1670
    • 10a Bayracharya GB, Daugulis O. Org. Lett. 2008; 10: 4625
    • 10b Dong Y, Lipschutz MI, Tilley TD. Org. Lett. 2016; 18: 1530
    • 10c Hazarika H, Gogoi P. Org. Biomol. Chem. 2020; 18: 2727
  • 11 The reaction of 3-chloro-2-ethoxypyridine gave 57% GC-yield compared to 90% GC-yield with 3-bromo-2-ethoxypyridine (4a).
  • 12 To demonstrate the importance of the presence of a substituent in position 2, we examined the reaction of 3-bromopyridine under the optimized conditions. Compared to 3-bromo-2-ethoxypyridine (90% GC-yield), the unsubstituted 3-bromopyridine gave only 32% GC-yield, presumably due to lower stability of the pyridyne intermediate.
  • 13 Koley M, Wimmer L, Schnürch M, Mihovilovic MD. Eur. J. Org. Chem. 2011; 1972