Silylium Ion Initiated Intramolecular Friedel–Crafts-Type Cyclization of 1,1-Difluoroalkenes with Subsequent Hydrodefluorination of C(sp3)–F Bonds

The strong electrophilicity of silylium ions has been leveraged to probe an intramolecular Friedel–Crafts-type cyclization of aryl-tethered 1,1-difluoroalkenes. The reaction is presumed to be initiated by a preferential electrophilic silylation of the carbon–carbon double bond over the activation of one of the vinylic C(sp²)–F bonds. Subsequent cyclization followed by hydrodefluorination of the resulting C(sp³)–F bonds leads to the final product. The resulting tetraline derivatives were obtained in moderate to good yields. Distinct from earlier reports, the reaction proceeds with the perfluorinated tetraphenylborate counteranion under ambient conditions without the prerequisite of a carborate counteranion associated with the silylium ion intermediates.

Key words

carbenium ions - cyclization - Friedel–Crafts reaction - hydrodefluorination - Lewis acids - silicon - silylium ions

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References

1a Scott VJ, Çelenligil-Çetin R, Ozerov OV. J. Am. Chem. Soc. 2005; 127: 2852
1b Panisch R, Bolte M, Müller T. J. Am. Chem. Soc. 2006; 128: 9676

2 Gusev DG, Ozerov OV. Chem. Eur. J. 2011; 17: 634

3a Stahl T, Klare HF. T, Oestreich M. ACS Catal. 2013; 3: 1578
3b Klare HF. T. ACS Catal. 2017; 7: 6999

4a Douvris C, Ozerov OV. Science 2008; 321: 1188
4b Douvris C, Nagaraja CM, Chen C.-H, Foxman BM, Ozerov OV. J. Am. Chem. Soc. 2010; 132: 4946

5a Kordts N, Künzler S, Rathjen S, Sieling T, Großekappenberg H, Schmidtmann M, Müller T. Chem. Eur. J. 2017; 23: 10068
5b Künzler S, Rathjen S, Rüger K, Würdemann MS, Wernke M, Tholen P, Girschik C, Schmidtmann M, Landais Y, Müller T. Chem. Eur. J. 2020; 26: 16441
5c Fernandes AJ, Robert F, Landais Y, Künzler S, Müller T. Chem. Eur. J. 2021; 27: 15496
5d Stahl T, Klare HF. T, Oestreich M. J. Am. Chem. Soc. 2013; 135: 1248

6a Klahn M, Fischer C, Spannenberg A, Rosenthal U, Krossing I. Tetrahedron Lett. 2007; 48: 8900

For a recent review on transition-metal-free C–F bond activation, see:

6b Ai H.-J, Ma X, Song Q, Wu X.-F. Sci. China: Chem. 2021; 64: 1630

7 Duttwyler S, Douvris C, Fackler NL. P, Tham FS, Reed CA, Baldridge KK, Siegel JS. Angew. Chem. Int. Ed. 2010; 49: 7519

8a Allemann O, Duttwyler S, Romanato P, Baldridge KK, Siegel JS. Science 2011; 332: 574
8b Shao B, Bagdasarian AL, Popov S, Nelson HM. Science 2017; 355: 1403

9a Ichikawa J, Jyono H, Kudo T, Fujiwara M, Yokota M. Synthesis 2005; 39
9b Ichikawa J, Yokota M, Kudo T, Umezaki S. Angew. Chem. Int. Ed. 2008; 47: 4870
9c Fuchibe K, Jyono H, Fujiwara M, Kudo T, Yokota M, Ichikawa J. Chem. Eur. J. 2011; 17: 12175
9d Suzuki N, Fujita T, Ichikawa J. Org. Lett. 2015; 17: 4984

Selected treatises on fluorinated carbocations:

10a Petrov VA, Bardin VV. In Organofluorine Chemistry: Fluorinated Alkenes and Reactive Intermediates . Chambers RD. Springer; Berlin/Heidelberg: 1997: 39
10b Shteingarts VD. In Carbocation Chemistry . Olah GA, Prakash GK. S. John Wiley & Sons, Inc; Hoboken: 2014: 159
10c Krespan CG, Petrov VA. Chem. Rev. 1996; 96: 3269

11 Klare HF. T, Oestreich M. J. Am. Chem. Soc. 2021; 143: 15490

12a Walker JC. L, Klare HF. T, Oestreich M. Nat. Rev. Chem. 2020; 4: 54
12b Klare HF. T, Albers L, Süsse L, Keess S, Müller T, Oestreich M. Chem. Rev. 2021; 121: 5889
12c Lee VYa, Sekiguchi A. In Organosilicon Compounds, Vol. 1. Lee VYa. Academic Press; Oxford: 2017: 197

13a Arii H, Nakabayashi K, Mochida K, Kawashima T. Molecules 2016; 21: 1
13b Arii H, Kurihara T, Mochida K, Kawashima T. Chem. Commun. 2014; 50: 6649
13c Arii H, Yano Y, Nakabayashi K, Yamaguchi S, Yamamura M, Mochida K, Kawashima T. J. Org. Chem. 2016; 81: 6314
13d Arii H, Nakao K, Masuda H, Kawashima T. ACS Omega 2022; 7: 5166

14 Douvris C, Stoyanov ES, Tham FS, Reed CA. Chem. Commun. 2007; 1145
15 He T, Klare HF. T, Oestreich M. ACS Catal. 2021; 11: 12186

16a An arenium adduct of a hydrogen-substituted silylium ion such as I ⁺ is likely not stable, undergoing competing loss of dihydrogen.
16b Albers L, Baumgartner J, Marschner C, Müller T. Chem. Eur. J. 2016; 22: 7970

For a quantum chemical prediction, see:

16c Ignatyev IS, Schaefer HF. III. J. Am. Chem. Soc. 2004; 126: 14515

17 Wigman B, Popov S, Bagdasarian AL, Shao B, Benton TR, Williams CG, Fisher SP, Lavallo V, Houk KN, Nelson HM. J. Am. Chem. Soc. 2019; 141: 9140

18a Wu Q, Qu Z.-W, Omann L, Irran E, Klare HF. T, Oestreich M. Angew. Chem. Int. Ed. 2018; 57: 9176
18b Wu Q, Irran E, Müller R, Kaupp M, Klare HF. T, Oestreich M. Science 2019; 365: 168

19 Rej S, Klare HF. T, Oestreich M. Org. Lett. 2022; 24: 1346
20 Furthermore, the substrate 1m-d ₅ with a perfluorinated o-phenylene moiety furnished 3m-d ₅ in C₆H₆, where significant deuterium incorporation was observed at the (homo)benzylic positions of 3m-d ₅. This outcome suggests multiple H/D-exchange processes initiated by the silylium ion reacting with the substrate in benzene solvent. See the Supporting Information for details.

21a He T, Klare HF. T, Oestreich M. J. Am. Chem. Soc. 2022; 144: 4734
21b Duttwyler S, Butterfield AM, Siegel JS. J. Org. Chem. 2013; 78: 2134

22 Harris RK, Becker ED, Cabral de Menezes SM, Goodfellow R, Granger P. Solid State Nucl. Magn. Reson. 2002; 22: 458
23 Fuqua SA, Duncan WG, Silverstein RM. J. Org. Chem. 1965; 30: 1027

24a Nador F, Moglie Y, Vitale C, Yus M, Alonso F, Radivoy G. Tetrahedron 2010; 66: 4318
24b Clive DL. J, Sunasee R, Chen Z. Org. Biomol. Chem. 2008; 6: 2434
24c Shen J, Li N, Yu Y, Ma C. Org. Lett. 2019; 21: 7179
24d Lo C.-Y, Kumar MP, Chang H.-K, Lush S.-F, Liu R.-S. J. Org. Chem. 2005; 70: 10482
24e Han B, Zhang M, Jiao H, Ma H, Wang J, Zhang Y. RSC Adv. 2021; 11: 39934
24f Ritu, Das S, Tian Y.-M, Karl T, Jain N, König B. ACS Catal. 2022; 12: 10326
24g Liu S, Fang M, Yin D, Wang Y, Liu L, Li X, Che G. Synth. Commun. 2019; 49: 942
24h Zhou X, Xu Y, Dong G. Nat. Catal. 2021; 4: 703

Zusatzmaterial

Supporting Information