CC BY-NC-ND 4.0 · Synlett 2022; 33(01): 45-47
DOI: 10.1055/a-1695-4516
cluster
Editorial Board Cluster

A Chiral Sulfoxide-Based C–H Acid

a  Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
,
Karl Kaupmees
b  University of Tartu, Institute of Chemistry, Ravila 14a, 50411 Tartu, Estonia
,
Ivo Leito
b  University of Tartu, Institute of Chemistry, Ravila 14a, 50411 Tartu, Estonia
,
a  Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
› Author Affiliations
Generous support by the European Research Council (Advanced Grant ‘C–H Acids for Organic Synthesis, CHAOS’) and the Deutsche Forschungsgemeinschaft (Leibniz Award to B.L. and Cluster of Excellence RESOLV, EXC 1069) is gratefully acknowledged. Work at Tartu was supported by the Estonian Research Council grant (PRG690), and by the EU through the European Regional Development Fund under project TK141 (2014-2020.4.01.15-0011).


Abstract

We report the design and synthesis of a strong, chiral, enantiopure sulfoxide-based C–H acid. Single-crystal X-ray analysis confirms the proposed structure and its absolute configuration. The new motif shows a high acidity and activity in Brønsted and Lewis acid catalyzed transformations. So far, only little to no enantioselectivities were achieved.

Supporting Information



Publication History

Received: 17 September 2021

Accepted after revision: 04 November 2021

Publication Date:
12 November 2021 (online)

© 2021. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 
  • References and Notes

    • 1a Akiyama T. Chem. Rev. 2007; 107: 5744
    • 1b Akiyama T, Mori K. Chem. Rev. 2015; 115: 9277
    • 1c Terada M, Kanomata K. Synlett 2011; 1255
    • 2a Mitschke B, Turberg M, List B. Chem 2020; 6: 2515
    • 2b Schreyer L, Properzi R, List B. Angew. Chem. Int. Ed. 2019; 58: 12761
  • 3 Trost BM, Rao M. Angew. Chem. Int. Ed. 2015; 54: 5026
    • 4a Robak MT, Trincado M, Ellman JA. J. Am. Chem. Soc. 2007; 129: 15110
    • 4b Kimmel KL, Weaver JD, Lee M, Ellman JA. J. Am. Chem. Soc. 2012; 134: 9058 ; corrigendum: J. Am. Chem. Soc. 2012, 134, 11828
  • 5 Turowsky L, Seppelt K. Inorg. Chem. 1988; 27: 2135
    • 6a Höfler D, van Gemmeren M, Wedemann P, Kaupmees K, Leito I, Leutzsch M, Lingnau JB, List B. Angew. Chem. Int. Ed. 2017; 56: 1411
    • 6b Höfler D, Goddard R, Nöthling N, List B. Synlett 2019; 30: 433
    • 6c Gatzenmeier T, van Gemmeren M, Xie Y, Höfler D, Leutzsch M, List B. Science 2016; 351: 949
    • 6d Gheewala CD, Collins BE, Lambert TH. Science 2016; 351: 961
    • 7a Wang X.-J, Liu J.-T. Tetrahedron 2005; 61: 6982
    • 7b Liu L.-J, Chen L.-J, Li P, Li X.-B, Liu J.-T. J. Org. Chem. 2011; 76: 4675
  • 8 1-{[Bis(triflyl)methyl]}sulfinylnonafluorobutane (1) A Schlenk flask was charged with bis(triflyl)methane (0.46 g, 1.6 mmol, 1.0 equiv) and THF (3.5 mL) to give a colorless clear solution that was cooled to −78 °C. A 1.2 M solution of TMP·MgCl·LiCl in THF (3.1 mL, 3.8 mmol, 2.3 equiv) was added dropwise, followed by the diastereomerically pure sulfinyl oxazolidinone 6a (4.3 g, 14 mmol, 1.0 equiv; dr >99:1) in THF (3.5 mL). The mixture was allowed to reach RT overnight. All volatiles were then removed under reduced pressure to give an orange solid that was dissolved in CH2Cl2 (30 mL) and washed with sat. aq. NaHCO3 (3 × 10 mL). The pooled aqueous phases were extracted with CH2Cl2 (2 × 10 mL). The pooled organic phases were washed with concd aq HCl (3 × 30 mL), dried (MgSO4), filtered, and concentrated under reduced pressure. The resulting yellowish viscous oil was dissolved in CH2Cl2 (30 mL), washed with concd H2SO4 (3 × 10 mL), stirred over dried BaCl2 for 80 min, and filtered. All volatiles were removed under reduced pressure until 7 mL of liquid remained. This solution was stored at –29 °C overnight, which led to the formation of a precipitate. The mother liquor was removed to give a colorless solid; yield: 0.51 g (57%, 0.93 mmol). LC/MS (chiral): (150 mm Chiralpak IC-3, 4.6 mm i.d., 30:70 MeCN–0.2% TFA, 1.0 mL/min, 20.8 MPa, 298 K): t R,(S)-enantiomer = 21.06 min, t R,(R)-enantiomer = 22.69 min; e.r. = 1:99. 13C NMR (151 MHz, acetone-d 6): δ = 123.74 (t, J = 23.1 Hz, C 6), 120.22 (q, J = ~322.0 Hz, C 7,8), 117.14 (tt, J = 322.7, 36.6 Hz, C 1), 114.51 (qt, J = 287.0, 32.5 Hz, C 4), 111.21 (tp, J = 266.2, 34.0 Hz, C2), 108.76 (th, J = 271.0, ~35 Hz, C 3). 19F NMR (471 MHz, acetone-d 6): δ = –179.16 (br, 3 F, F7,8 ), –80.68 (br, 3 F, F7,8 ), –81.37 to –82.51 (td, J = 9.6, 5.1 Hz, 3 F, F4 ), –103.82 (br d, J = 220.6 Hz, 1 F, F1′ ), –121.02 (dt, J = 221.8, 10.3 Hz, 1 F, F1′′ ), –123.63 [br d (AB system), J = ~300.0 Hz, 1 F, F2′ ], –124.33 [br d (AB system), J = ~300.0 Hz, 1 F, F2′ ], –126.39 [br d (AB system), J = 293.0 Hz, 1 F, F3′ ], –127.19 [br d (AB system), J = 293.0 Hz, 1F, F3′′ ]. MS (ESI–): m/z = 545 [M –H]. HRMS (ESI–): m/z [M –H] calcd for C7F15O5S3: 544.8674; found: 544.8674. Anal.: Calcd for C7HF15O5S3 (546.24 g/mol): C, 15.39; H, 0.18; F, 52.17; S, 17.61; Found: C, 15.42; H, 0.17; F, 52.14; S, 17.60.
  • 9 CCDC 2106642 and 2106643 contain the supplementary crystallographic data for 1 hydroxonium hydrate and 6a. The data can be obtained free of charge from The Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/structures
  • 10 Paenurk E, Kaupmees K, Himmel D, Kütt A, Kaljurand I, Koppel IA, Krossing I, Leito I. Chem. Sci. 2017; 8: 6964
  • 11 Kütt A, Rodima T, Saame J, Raamat E, Mäemets V, Kaljurand I, Koppel IA, Garlyauskayte RY, Yagupolskii YL, Yagupolskii LM, Bernhardt E, Willner H, Leito I. J. Org. Chem. 2011; 76: 391