Synlett 2014; 25(11): 1539-1541
DOI: 10.1055/s-0034-1378348
cluster
© Georg Thieme Verlag Stuttgart · New York

Polyfluorinated Cyclopentadienones as Lewis Acids

Blanca Inés
Max-Planck-Institut für Kohlenforschung, Kaiser Wilhelm Platz 1, 45470 Mülheim an der Ruhr, Germany   Fax: +49(208)3062428   Email: alcarazo@mpi-muelheim.mpg.de
,
Sigrid Holle
Max-Planck-Institut für Kohlenforschung, Kaiser Wilhelm Platz 1, 45470 Mülheim an der Ruhr, Germany   Fax: +49(208)3062428   Email: alcarazo@mpi-muelheim.mpg.de
,
Dominique A. Bock
Max-Planck-Institut für Kohlenforschung, Kaiser Wilhelm Platz 1, 45470 Mülheim an der Ruhr, Germany   Fax: +49(208)3062428   Email: alcarazo@mpi-muelheim.mpg.de
,
Manuel Alcarazo*
Max-Planck-Institut für Kohlenforschung, Kaiser Wilhelm Platz 1, 45470 Mülheim an der Ruhr, Germany   Fax: +49(208)3062428   Email: alcarazo@mpi-muelheim.mpg.de
› Author Affiliations
Further Information

Publication History

Received: 29 April 2014

Accepted after revision: 03 June 2014

Publication Date:
11 June 2014 (online)

Abstract

The ability of 2,3,4,5-tetrakis(trifluoromethyl)cyclopenta-2,4-dien-1-one and 2,3,4,5-tetrakis(pentafluorophenyl)cyclopenta-2,4-dien-1-one to act as organic Lewis acids in the field of frustrated Lewis pair (FLP) chemistry was evaluated. Whereas the former ketone formed zwitterionic adducts with all phosphines studied, the latter did not react with bulky phosphines and, instead, gave completely organic FLPs. Unfortunately, these did not activate dihydrogen, even under high pressures.

Supporting Information

 
  • References

    • 1a Welch GC, San Juan RR, Masuda JD, Stephan DW. Science 2006; 314: 1124
    • 1b Kenward AL, Piers WE. Angew. Chem. Int. Ed. 2008; 47: 38

    • For a recent review on the chemistry of frustrated Lewis pairs see:
    • 1c Stephan DW, Erker G. Angew. Chem. Int. Ed. 2010; 49: 46

    • For metal-free catalyzed hydrogenation see:
    • 1d Spies P, Schwendermann S, Lange S, Kehr G, Fröhlich R, Erker G. Angew. Chem. Int. Ed. 2008; 47: 7543
    • 1e Chase PA, Welch GC, Jurca T, Stephan DW. Angew. Chem. Int. Ed. 2007; 46: 8050
    • 1f Greb L, Daniliuc C.-G, Bergander K, Paradies J. Angew. Chem. Int. Ed. 2013; 52: 5876
    • 1g Nicasio JA, Steinberg S, Inés B, Alcarazo M. Chem. Eur. J. 2013; 19: 11016
    • 2a Rosorius C, Kehr G, Fröhlich R, Grimme S, Erker G. Organometallics 2011; 30: 4211
    • 2b Theuergarten E, Schlösser J, Schluns D, Freytag M, Daniliuc CG, Jones PG, Tamm M. Dalton Trans. 2012; 41: 9101
  • 3 Cárdenas AJ. P, Culotta BJ, Warren TH, Grimme S, Stute A, Fröhlich R, Kehr G, Erker G. Angew. Chem. Int. Ed. 2011; 50: 7567
    • 4a Dureen MA, Welch GC, Gilbert TM, Stephan DW. Inorg. Chem. 2009; 48: 9910
    • 4b Inés B, Holle S, Goddard R, Alcarazo M. Angew. Chem. Int. Ed. 2010; 49: 8389
    • 4c Alcarazo M. Dalton Trans. 2011; 40: 1839
    • 4d Palomas D, Holle S, Inés B, Bruns H, Goddard R, Alcarazo M. Dalton Trans. 2012; 41: 9073
    • 5a Parks DJ, Piers WE. J. Am. Chem. Soc. 1996; 118: 9440
    • 5b Parks DJ, Blackwell JM, Piers WE. J. Org. Chem. 2000; 65: 3090
    • 5c Alcarazo M, Gomez C, Holle S, Goddard R. Angew. Chem. Int. Ed. 2010; 49: 5788
    • 5d Chen D, Leich V, Pang F, Klankermayer J. Chem. Eur. J. 2012; 18: 5184
  • 6 Holschumacher D, Bannenberg T, Hrib CG, Jones PG, Tamm M. Angew. Chem. Int. Ed. 2008; 47: 7428
    • 7a Sumerin V, Schulz F, Nieger M, Leskelä M, Repo T, Rieger B. Angew. Chem. Int. Ed. 2008; 47: 6001
    • 7b Chase P, Jurca T, Stephan DW. Chem. Commun. 2008; 1701
  • 8 Geier SJ, Gille AL, Gilgert TM, Stephan DW. Inorg. Chem. 2009; 48: 10466
  • 9 Inés B, Palomas D, Holle S, Steinberg S, Nicasio JA, Alcarazo M. Angew. Chem. Int. Ed. 2012; 51: 12367
  • 10 Cabrera L, Welch GC, Masuda JD, Wei P, Stephan DW. Inorg. Chim. Acta 2006; 359: 3066
  • 11 Iglesias-Sigüenza J, Alcarazo M. Angew. Chem. Int. Ed. 2012; 51: 1523
  • 12 Dickson RS, Wilkinson G. J. Chem. Soc. 1964; 2699

    • It has been demonstrated that the primary attack takes place at the carbon at the position α to the carbonyl group, but even at low temperatures this intermediate rearranges to the thermodynamically more stable 2, See:
    • 13a Roundhill DM, Wilkinson G. J. Org. Chem. 1970; 35: 3561
    • 13b Burk MJ, Calabrese JC, Davison F, Harlow RL, Roe DC. J. Am. Chem. Soc. 1991; 113: 2209
  • 14 Crystallographic data for compounds 6, 7, 8, 11, 12, and 14 have been deposited with the accession numbers CCDC 999847, 999844, 999846, 999848, 999843 , and 999845, respectively, and can be obtained free of charge from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; Fax: +44(1223)336033; E-mail: deposit@ccdc.cam.ac.uk; Web site: www.ccdc.cam.ac.uk/conts/retrieving.html.
    • 15a Bauer R, Liu D, Ver Heyen A, De Schryver F, De Feyter S, Müllen K. Macromolecules 2007; 40: 4753

    • A new procedure has been recently reported, see:
    • 15b Löser P, Winzenburg A, Faust R. Chem. Commun. 2013; 49: 9413
  • 16 In a typical reaction, the appropriate phosphine was added in one portion to a solution of ketone 9 in toluene at r.t., and the resulting slurry was stirred at r.t. overnight. The solvent was then removed under vacuum and the crude product washed with pentane. 12: yellow solid; yield: 66 mg (86%); mp 235 °C (decomp.); IR (neat): 742, 856, 926, 991, 1053, 1093, 1104, 1347, 1402, 1494, 1504, 1523, 1978 cm–1; 1H NMR (400 MHz, CD2Cl2): δ = 1.40 (d, J = 14.7 Hz, 27 H); 13C NMR (151 MHz, CD2Cl2): δ = 29.2, 42.1 (d, J = 33.9 Hz), 77.9, 96.1, 104.2, 113.6 (m), 114.0 (m), 137.2 (dm, J = 250.4 Hz), 137.9 (dm, J = 251.8 Hz), 139.6 (dm, J = 249.0 Hz), 139.9 (dm, J = 249.0 Hz), 144.7 (dm, J = 246.2 Hz), 145.5 (dm, J = 243.4 Hz); 31P NMR (162 MHz, CD2Cl2): δ = 106.7; 19F NMR (282 MHz, CDCl3): δ = –(165.21–165.02) (m, 4 F), –(164.00–163.80) (m, 4 F), –(158.86–158.52) (m, 4 F), –(140.25–140.14) (m, 4 F), –(139.00–138.85) (m, 4 F); HRMS: m/z [M + Na]+ calcd for C41H27OF20PNa: 969.137244; found: 969.137923. 14: yellow solid; yield: 50 mg (93%); mp 229 °C (decomp.); IR (neat): 790, 852, 864, 894, 924, 969, 991, 1060, 1094, 1106, 1287, 1358, 1403, 1475, 1490, 1501, 1522, 1535, 2862, 2933; 1H NMR (400 MHz, CD2Cl2): δ = 0.83–1.00 (m, 4 H), 1.07–1.27 (m, 6 H), 1.38–1.72 (m, 10 H), 2.01–2.12 (m, 2 H), 7.26–7.29 (m, 1 H), 7.32–7.38 (m, 3 H), 7.44–7.48 (m, 1 H), 7.55–7.57 (m, 3 H), 7.70–7.74 (m, 1 H); 13C NMR (101 MHz, CD2Cl2) (partial): δ = 25.7 (d, J = 1.4 Hz), 26.3 (d, J = 3.8 Hz), 26.9 (d, J = 13.3 Hz), 37.2 (d, J = 51.9 Hz), 83.2, 95.5, 103.5, 113.0, 114.0, 127.7 (d, J = 11.4 Hz), 129.2, 129.7, 130.3, 131.9 (d, J = 10.0 Hz), 134.6 (d, J = 14.3 Hz), 134.7, 137.5 (dm, J = 242.7 Hz), 137.9 (dm, J = 247.0 Hz), 139.5 (d, J = 2.4 Hz), 144.7 (dm, J = 242.7 Hz), 145.5 (dm, J = 240.3 Hz), 148.5 (d, J = 8.6 Hz); 31P NMR (162 MHz, CD2Cl2): δ = 80.5; 19F NMR (282 MHz, CDCl3): δ = –(165.21–165.09) (m, 4 F), –(163.99–163.84) (m, 4 F), –159.68 (t, J = 21.1 Hz, 2 F), –159.36 (t, J = 21.0 Hz, 2 F), –(140.52–140.34) (m, 4 F), –139.77 (dt, J = 25.0, 8.7 Hz, 4 F); HRMS: m/z [M + Na]+ calcd for C53H31OF20PNa: 1117.168543; found: 1117.169092.