Copper(I) Halide Mediated Tandem
1,4-Aryl Migration-Oxidative Amidyl Radical Cyclisation
of Bromosulfonamides

Andrew J. Clark; David R. Fullaway; Nicholas P. Murphy; Hemal Parekh

doi:10.1055/s-0029-1219151

LETTER

Copper(I) Halide Mediated Tandem 1,4-Aryl Migration-Oxidative Amidyl Radical Cyclisation of Bromosulfonamides

Andrew J. Clark*, David R. Fullaway, Nicholas P. Murphy, Hemal Parekh
Department of Chemistry, University of Warwick, Coventry, West Midlands, CV4 7AL, UK
Fax: +44(2476)524112; e-Mail: a.j.clark@warwick.ac.uk;

Abstract

All articles of this category

Abstract

Reaction of N-butyl-N-(2-bromo-2-methylpropionyl)-arylsulfonamides with CuBr/tripyridylamine leads to amidyl radicals via 1,4-aryl migration with concomitant loss of SO₂, which can further undergo cyclisation to oxindoles or reduction to amides with the ratio dependent upon the temperature and solvent utilised.

Key words

copper - radical reactions - rearrangement - tandem reactions - sulfonamides

Full Text

References

References and Notes

<A NAME="RD28709ST-1">1</A> Clark AJ. Coles SR. Collis A. Debure T. Guy C. Murphy NP. Wilson P. Tetrahedron Lett. 2009, 50: 5609

<A NAME="RD28709ST-2">2</A> Clark AJ. Coles SR. Collis A. Fullaway DR. Murphy NP. Wilson P. Tetrahedron Lett. 2009, 50: 6311

<A NAME="RD28709ST-3A">3a</A> Loven R. Speckamp WN. Tetrahedron Lett. 1972, 13: 1567

<A NAME="RD28709ST-3B">3b</A> Köhler JJ. Speckamp WN. Tetrahedron Lett. 1977, 18: 631

<A NAME="RD28709ST-3C">3c</A> Köhler JJ. Speckamp WN. Tetrahedron Lett. 1977, 18: 635

<A NAME="RD28709ST-3D">3d</A> Köhler JJ. Speckamp WN. J. Chem. Soc., Chem. Commun. 1978, 166

<A NAME="RD28709ST-3E">3e</A> Köhler JJ. Speckamp WN. J. Chem. Soc., Chem. Commun. 1980, 142

<A NAME="RD28709ST-3F">3f</A> Clive DLJ. Boivin TLB. J. Org. Chem. 1989, 54: 1997

<A NAME="RD28709ST-3G">3g</A> Motherwell WB. Pennell AMK. J. Chem. Soc., Chem. Commun. 1991, 877

<A NAME="RD28709ST-3H">3h</A> da Mata MLEN. Motherwell WB. Ujjainwalla F. Tetrahedron Lett. 1997, 38: 137

<A NAME="RD28709ST-3I">3i</A> da Mata MLEN. Motherwell WB. Ujjainwalla F. Tetrahedron Lett. 1997, 38: 141

<A NAME="RD28709ST-3J">3j</A> Bonfand E. Forsland L. Motherwell WB. Vázquez S. Synlett 2000, 475

<A NAME="RD28709ST-3K">3k</A> Studer A. Boassart M. Tetrahedron 2001, 57: 9649

<A NAME="RD28709ST-3L">3l</A> Bossart M. Fässler R. Schoenberger J. Studer A. Eur. J. Org. Chem. 2002, 2742

<A NAME="RD28709ST-3M">3m</A> Gheorghe A. Quiclet-Sire B. Vila X. Zard SZ. Org. Lett. 2005, 7: 1653

<A NAME="RD28709ST-4">4</A> Clark AJ. Chem. Soc. Rev. 2002, 31: 1

<A NAME="RD28709ST-5A">5a</A> Clark AJ. Filik RP. Thomas GH. Tetrahedron Lett. 1999, 40: 4885

<A NAME="RD28709ST-5B">5b</A> Clark AJ. De Campo F. Deeth RJ. Filik RP. Gatard S. Hunt NA. Lastécouères D. Thomas GH. Verlac J.-B. Wongtap H. J. Chem. Soc., Perkin Trans. 1 2000, 671

<A NAME="RD28709ST-5C">5c</A> Clark AJ. Geden JV. Thom S. Wilson P. J. Org. Chem. 2006, 71: 1471

<A NAME="RD28709ST-6A">6a</A> Nagashima H. Ozaki N. Ishii M. Seki K. Washiyama M. Itoh K. J. Org. Chem. 1993, 58: 464

<A NAME="RD28709ST-6B">6b</A> Iwamatsu S. Matsubara K. Nagashima H. J. Org. Chem. 1999, 64: 9625

<A NAME="RD28709ST-6C">6c</A> Nagashima H. Isono Y. Iwamatsu S. J. Org. Chem. 2001, 66: 315

<A NAME="RD28709ST-7A">7a</A> Ghelfi F. Pattarozzi M. Roncaglia F. Parsons AF. Felluga F. Pagnoni UM. Valentin E. Mucci A. Bellesia F. Synthesis 2008, 3131

<A NAME="RD28709ST-7B">7b</A> Ghelfi F. Stevens CV. Laureyn I. Van Meenen E. Rogge TM. De Buyck L. Nikitin KV. Grandi R. Libertini E. Pagnoni UM. Schenetti L. Synthesis 2007, 1882

<A NAME="RD28709ST-7C">7c</A> Bellesia F. Daniel C. De Buyck L. Galeazzi R. Ghelfi F. Mucci A. Orean M. Pagnoni UM. Parsons AF. Roncaglia F. Tetrahedron 2006, 62: 746

<A NAME="RD28709ST-7D">7d</A> Bryans JS. Chessum NEA. Huther N. Parsons AF. Ghelfi F. Tetrahedron 2003, 59: 6221

<A NAME="RD28709ST-7E">7e</A> Cagnoli R. Ghelfi F. Pagnoni UM. Parsons AF. Schenetti L. Tetrahedron 2003, 59: 9951

<A NAME="RD28709ST-7F">7f</A> Ghelfi F. Parsons AF. J. Org. Chem. 2000, 65: 6249

<A NAME="RD28709ST-7G">7g</A> Ghelfi F. Bellesia F. Forti L. Ghirardini G. Grandi R. Libertini E. Montemaggi MC. Pagnoni UM. Pinetti A. De Buyck L. Parsons AF. Tetrahedron 1999, 55: 5839

<A NAME="RD28709ST-7H">7h</A> Benedetti M. Forti L. Ghelfi F. Pagnoni UM. Ronzoni R. Tetrahedron 1997, 41: 14031

<A NAME="RD28709ST-8A">8a</A> Clark AJ. Dell CP. McDonagh JP. C. R. Acad. Sci.. Ser. IIC 2001, 4: 575

<A NAME="RD28709ST-8B">8b</A> Clark AJ. Battle GM. Bridge A. Tetrahedron Lett. 2001, 42: 1999

<A NAME="RD28709ST-8C">8c</A> Clark AJ. Battle GM. Bridge A. Tetrahedron Lett. 2001, 42: 2003

<A NAME="RD28709ST-8D">8d</A> Clark AJ. Battle GM. Bridge A. Tetrahedron Lett. 2001, 42: 4409

<A NAME="RD28709ST-8E">8e</A> Clark AJ. Geden JV. Thom S. Wilson P. J. Org. Chem. 2006, 71: 1471

<A NAME="RD28709ST-8F">8f</A> Clark AJ. Geden JV. Thom S. Wilson P. J. Org. Chem. 2007, 72: 5923

<A NAME="RD28709ST-8G">8g</A> Clark AJ. Wilson P. Tetrahedron Lett. 2008, 49: 4848

<A NAME="RD28709ST-9">9</A> Baillet G. Campredon M. Guglielmetti R. Giusti G. Aubert C. J. Photochem. Photobiol.. A 1994, 83: 147

<A NAME="RD28709ST-10">10</A> Montermini F. Lacote E. Malacria M. Org. Lett. 2004, 6: 921

<A NAME="RD28709ST-11">11</A> For a review on aromatic homolytic substitution, see: Bowman WR. Storey JMD. Chem. Soc. Rev. 2007, 36: 1803

<A NAME="RD28709ST-12">12</A> Clark AJ. Filik RP. Peacock JL. Thomas GH. Synlett 1999, 441

<A NAME="RD28709ST-13">13</A> Godfrey CRA. Hegarty P. Motherwell WB. Ujjainwalla F. Tetrahedron Lett. 1998, 39: 723

2-Bromo-N-butyl-2-methyl-N-4-tolylpropanamide (1.50 g, 4.8 mmol) was added to anhyd AlCl₃ (1.62 g, 12.1 mmol) under a stream of nitrogen. The mixture was heated at 50 ˚C for 10 min and then maintained at 160 ˚C for 1 h. The mixture was washed with H₂O (5 × 50 mL) and extracted with Et₂O, dried over MgSO₄, and evaporated to give 16c (0.45 g, 41%) after chromatography (PE-EtOAc, 10:1); R _f = 0.40 (PE-EtOAc, 10:1). IR: ν_max = 2962, 2929, 2865, 1705, 1619, 1599, 1493, 1381, 1351, 1192 cm^-¹. ^¹H NMR (400 MHz, CDCl₃): δ = 7.04 (1 H, d, J = 8.0 Hz), 7.03 (1 H, s), 6.75 (1 H, d, J = 8.0 Hz), 3.69 (2 H, t, J = 8.0 Hz), 2.34 (3 H, s), 1.65 (2 H, quin, J = 8.0 Hz), 1.35 (2 H, sext, J = 8.0 Hz), 1.35 (3 H, s), 0.94 (3 H, t, J = 8.0 Hz). ^¹³C NMR (75.5 MHz, CDCl₃): δ = 181.3, 139.7, 136.1, 131.7, 127.7, 123.3, 108.1, 44.1, 39.6, 29.5, 24.5, 21.1, 20.1, 13.8. ESI-HRMS: m/z calcd for Na⁺C₁₅H₂₁NO: 254.1515; found [Na⁺]: 254.1522.
Data for the Mixture of 8c and 19
IR: ν_max = 2963, 2931, 2871, 1707, 1606, 1462, 1383, 1343, 1223 cm^-¹. ESI-HRMS: m/z calcd for Na⁺C₁₅H₂₁NO: 254.1515; found [Na⁺]: 254.1519.
Data for 19
^¹H NMR (400 MHz, CDCl₃): δ = 7.14 (1 H, t, J = 8.0 Hz), 6.81 (1 H, d, J = 8.0 Hz), 6.71 (1 H, d, J = 8.0 Hz), 3.70 (2 H, t, J = 8.0 Hz), 2.40 (3 H, s), 1.65 (2 H, quin, J = 8.0 Hz), 1.44 (3 H, s), 1.37 (2 H, sext, J = 8.0 Hz), 0.94 (3 H, t, J = 8.0 Hz). ^¹³C NMR (75.5 MHz, CDCl₃): δ = 181.3, 142.3, 134.2, 132.8, 127.4, 124.7, 106.1, 44.9, 39.6, 29.5, 22.4, 20.1, 18.2, 13.8.
Data for 8c
^¹H NMR (400 MHz, CDCl₃): δ = 7.08 (1 H, d, J = 8.0 Hz), 6.86 (1 H, d, J = 8.0 Hz), 6.68 (1 H, s), 3.69 (2 H, t, J = 8.0 Hz), 2.38 (3 H, s), 1.65 (2 H, quin, J = 8.0 Hz), 1.37 (2 H, sext, J = 8.0 Hz), 1.34 (3 H, s), 0.95 (3 H, t, J = 8.0 Hz). ^¹³C NMR (75.5 MHz, CDCl₃): δ = 181.3, 142.3, 137.6, 133.2, 122.6, 122.1, 109.2, 43.8, 39.5, 29.6, 24.6, 21.8, 20.1, 13.8.

A typical procedure is illustrated for reaction of 1b with CuBr (entry 2, Table [¹] ). Substrate 1b (0.3 mmol) was added to dry CH₂Cl₂ (2 mL), and CuBr (0.33 mmol) and tripyridylamine (0.33 mmol) were added. The reaction mixture was heated at 40 ˚C for 18 h. Upon cooling, the crude mixture was passed through a small silica plug (eluting with EtOAc, 20 mL to remove copper residues). After evaporation of the solvent and chromatography (PE-EtOAc, 8:1) a mixture of amide 3b and oxindole 8b were isolated in the ratio of 1.4:1.0, combined yield 78%. Spectroscopic data for 3b were identical to an authentic sample prepared previously^²,9 and data for 8b were identical to that reported above.^¹4

<A NAME="RD28709ST-16">16</A> Moutrille C. Zard SZ. Chem. Commun. 2004, 1848

For reviews on nitrogen-centered radicals, see:

<A NAME="RD28709ST-17A">17a</A> Zard SZ. Synlett 1996, 1148

<A NAME="RD28709ST-17B">17b</A> Esker JL. Newcomb M. Adv. Heterocycl. Chem. 1993, 58: 1

<A NAME="RD28709ST-18">18</A> Clark AJ. Peacock JL. Tetrahedron Lett. 1998, 39: 1265

<A NAME="RD28709ST-19A">19a</A> Newcomb M. Esker JL. Tetrahedron Lett. 1991, 32: 1035

<A NAME="RD28709ST-19B">19b</A> Esker JL. Newcomb M. J. Org. Chem. 1993, 58: 4933

<A NAME="RD28709ST-19C">19c</A> Horner JH. Musa OM. Bouvier A. Newcomb M. J. Am. Chem. Soc. 1998, 120: 7738

<A NAME="RD28709ST-20A">20a</A> Clark AJ. Peacock JL. Tetrahedron Lett. 1998, 39: 6029

<A NAME="RD28709ST-20B">20b</A> Clark AJ. Deeth RJ. Samuel CJ. Wongtap HL. Synlett 1999, 444

<A NAME="RD28709ST-21A">21a</A> Lin X. Stien D. Weinreb SM. Tetrahedron Lett. 2000, 41: 2333

<A NAME="RD28709ST-21B">21b</A> Artman GD. Stien D. Weinreb SM. Synthesis 2002, 2057

<A NAME="RD28709ST-22A">22a</A> Callier A.-C. Quiclet-Sire B. Zard SZ. Tetrahedron Lett. 1994, 35: 6109

<A NAME="RD28709ST-22B">22b</A> Callier-Dubalanchet A.-C. Quiclet-Sire B. Zard SZ. Tetrahedron Lett. 1995, 36: 8791

<A NAME="RD28709ST-22C">22c</A> Sharp LA. Zard SZ. Org. Lett. 2006, 8: 831

<A NAME="RD28709ST-23A">23a</A> Tang Y. Li C. Org. Lett. 2004, 6: 3229

<A NAME="RD28709ST-23B">23b</A> Chen Q. Shen M. Tang Y. Li CZ. Org. Lett. 2005, 7: 1625

<A NAME="RD28709ST-23C">23c</A> Lu HJ. Chen Q. Li CZ. J. Org. Chem. 2007, 72: 2564

<A NAME="RD28709ST-23D">23d</A> Yuan XT. Liu K. Li CZ. J. Org. Chem. 2008, 73: 6166

<A NAME="RD28709ST-24">24</A> Yu Y.-Y. Fu Y. Xie M. Liu L. Guo Q.-X. J. Org. Chem. 2007, 72: 8025

<A NAME="RD28709ST-25">25</A> Rey V. Pierini AB. Peňéňory AB. J. Org. Chem. 2009, 74: 1223

<A NAME="RD28709ST-26">26</A> Qiu J. Matyjaszewski K. Thouin L. Amatore C. Macromol. Chem. Phys. 2000, 201: 1625