Palladium-Catalyzed Silylation of Aryl Chlorides with Bulky Dialkoxydisilanes

Abstract

Arylsilanes bearing a bulky alkoxy group on the silicon were synthesized from aryl chlorides and dialkoxydisilanes under reaction conditions utilizing SingaCycle-A3 as a palladium precatalyst and lithium benzoate in wet DMA. This report proposes the first direct and catalytic method for introducing tert-butoxy- or 1-adamantyloxysilyl groups onto various aryl moieties through the silylation reaction.

Key words

palladium - alkoxysilane - disilane - arylsilane

• References and Notes

• 1a Organosilicon Chemistry . Hiyama T, Oestreich M. Wiley-VCH; Weinheim: 2019
• 1b Hiyama T. In Organometallics in Synthesis: Third Manual . Schlosser M. Wiley; Hoboken: 2013: 373
• 1c Science of Synthesis, Vol. 4 . Fleming I. Thieme; Stuttgart: 2002
• 1d Brook MA. Silicon in Organic, Organometallic, and Polymer Chemistry. Wiley; New York: 2000
• 1e Organosilicon Chemistry Set: From Molecules to Materials . Auner N, Weis J. Wiley-VCH; Weinheim: 1994
• 2a Tamao K, Kobayashi K, Ito Y. Tetrahedron Lett. 1989; 30: 6051
• 2b Denmark SE, Sweis RF. Acc. Chem. Res. 2002; 35: 835
• 2c Li L, Navasero N. Org. Lett. 2004; 6: 3091
• 3a Martin SE. S, Watson DA. J. Am. Chem. Soc. 2013; 135: 13330
• 3b Saito H, Nogi K, Yorimitsu H. Angew. Chem. Int. Ed. 2018; 57: 11030
• 4 Hiyama–Denmark-type coupling reaction of an arylsilane bearing tBuOMe₂Si group with 4-iodoanisole under unoptimized conditions gave the cross-coupling product in ca. 40% yield.
• 5a Murata M, Suzuki K, Watanabe S, Masuda Y. J. Org. Chem. 1997; 62: 8569
• 5b Manoso AS, DeShong P. J. Org. Chem. 2001; 66: 7449
• 5c Murata M, Ishikura M, Nagata M, Watanabe S, Masuda Y. Org. Lett. 2002; 4: 1843
• 5d Denmark SE, Kallemeyn JM. Org. Lett. 2003; 5: 3483
• 5e Hamze A, Provot O, Alami M, Brion J.-D. Org. Lett. 2006; 8: 931
• 5f Karshtedt D, Bell AT, Tilley DT. Organometallics 2006; 25: 4471
• 5g Iizuka M, Kondo Y. Eur. J. Org. Chem. 2008; 1161
• 5h Kurihara Y, Yamanoi Y, Nishihara H. Chem. Commun. 2013; 49: 11275
• 6a Guo H, Chen X, Zhao C, He W. Chem. Commun. 2015; 51: 17410
• 6b Liu X.-W, Zarate C, Martin R. Angew. Chem. Int. Ed. 2019; 58: 2064
• 7a Matsumoto H, Nagashima S, Yoshihiro K, Nagai Y. J. Organomet. Chem. 1975; 85: C1
• 7b Azarian D, Dua SS, Eaborn C, Walton D. J. Organomet. Chem. 1976; 117: C55
• 7c Matsumoto H, Yoshihiro K, Nagashima S, Watanabe H, Nagai Y. J. Organomet. Chem. 1977; 128: 409
• 7d Matsumoto H, Shono K, Nagai Y. J. Organomet. Chem. 1981; 208: 145
• 7e Eaborn C., Griffiths R. W., Pidcock A.; J. Organomet. Chem.; 1982, 225: 331.
• 7f Matsumoto H, Kasahara M, Matsubara I, Takahashi M, Arai T, Hasegawa M, Nakano T, Nagai Y. J. Organomet. Chem. 1983; 250: 99
• 7g Hatanaka Y, Hiyama T. Tetrahedron Lett. 1987; 28: 4715
• 7h Babin P, Bennetau B, Theurig M, Dunoguès J. J. Organomet. Chem. 1993; 446: 135
• 7i Shirakawa E, Kurahashi T, Yoshida H, Hiyama T. Chem. Commun. 2000; 1895
• 7j Gooßen LJ, Ferwanah A.-RS. Synlett 2000; 1801
• 7k McNeill E, Barder TE, Buchwald SL. Org. Lett. 2007; 9: 3785
• 7l Minami Y, Shimizu K, Tsuruoka C, Komiyama T, Hiyama T. Chem. Lett. 2014; 43: 201
• 7m Yamamoto Y, Matsubara H, Murakami K, Yorimitsu H, Osuka A. Chem. Asian J. 2015; 10: 219
• 8 Kantchev EA. B, Ying JY. Organometallics 2009; 28: 289
• 9 Ethyl 4-(tert-butoxydimethylsilyl)benzoate (6a) – Typical Procedure An oven-dried 30 mL Schlenk tube was charged with LiOBz (96.0 mg, 0.75 mmol), SingaCycle-A3 (10.0 mg, 0.015 mmol), and DMA (1.5 mL) under nitrogen atmosphere. Ethyl 4-chlorobenzoate (4a, 92.3 mg, 0.50 mmol), 1,2-di-tert-butoxy-1,1,2,2-tetramethydisilane (5, 235 μL, 0.75 mmol), and H₂O stock solution (0.17 M in DMA, 0.15 mL, 25 μmol) were sequentially added to the mixture. DMA (1.35 mL) was added to wash the inner side of the tube. The reaction mixture was stirred at 100 °C for 12 h and quenched with sat. aq NaHCO₃ (10 mL). The mixture was poured into a separatory funnel with EtOAc (20 mL) and partitioned. The organic phase was collected and washed with sat. aq NaHCO₃ (10 mL), sat. aq NH₄Cl (10 mL), brine (10 mL), dried over anhydrous Na₂SO₄ (ca. 5 g), filtered, and concentrated in vacuo. The residue was purified by column chromatography on silica gel with an eluent (hexane and hexane/EtOAc = 100:1) to afford 6a (105.6 mg, 0.38 mmol, 75%) as colorless oil. ¹H NMR (CDCl₃, 600 MHz): δ = 8.01 (d, J = 8.2 Hz, 2 H), 7.67 (d, J = 8.2 Hz, 2 H), 4.38 (q, J = 6.9 Hz, 2 H), 1.39 (t, J = 6.9 Hz, 3 H), 1.25 (s, 9 H), 0.39 (s, 6 H). ¹³C NMR (CDCl₃, 151 MHz): δ = 167.0, 146.8, 133.4, 131.0, 128.6, 73.2, 61.0, 32.2, 14.5, 1.5. HRMS: m/z calcd for C₁₅H₂₅O₃Si [M + H]⁺: 281.1567; found: 281.1569.
• 10 O’Brien CJ, Kantchev EA. B, Valente C, Hadai N, Chass GA, Lough A, Hopkinson AC, Organ MG. Chem. Eur. J. 2006; 12: 4743
• 11 1-[4-(tert-Butoxydimethylsilyl)phenyl]ethan-1-one (6b) Reaction time was 12 h. Column chromatography with an eluent (hexane to hexane/EtOAc = 30:1) afforded 6b as colorless oil (85.9 mg, 0.34 mmol, 69%) from 4b (77.3 mg, 0.50 mmol). ¹H NMR (CDCl₃, 600 MHz): δ = 7.92 (d, J = 8.2 Hz, 2 H), 7.70 (d, J = 8.2 Hz, 2 H), 2.61 (s, 3 H), 1.26 (s, 9 H), 0.39 (s, 6 H). ¹³C NMR (CDCl₃, 151 MHz): δ = 198.6, 147.3, 137.5, 133.7, 127.3, 73.2, 32.2, 26.8, 1.5. HRMS: m/z calcd for C₁₄H₂₃O₂Si [M + H]⁺: 251.1462; found: 251.1461.
• 12 4-(tert-Butoxydimethylsilyl)benzonitrile (6c) Reaction time was 12 h. Column chromatography with an eluent (hexane to hexane/EtOAc = 100:1) afforded 6c as colorless oil (89.6 mg, 0.38 mmol, 77%) from 4c (68.8 mg, 0.50 mmol). ¹H NMR (CDCl₃, 600 MHz): δ = 7.68 (d, J = 8.2 Hz, 2 H), 7.62 (d, J = 8.2 Hz, 2 H), 1.26 (s, 9 H), 0.39 (s, 6 H). ¹³C NMR (CDCl₃, 151 MHz): δ = 147.4, 133.9, 131.1, 119.3, 112.7, 73.4, 32.2, 1.5. HRMS: m/z calcd for C₁₃H₂₀NOSi [M + H]⁺: 234.1309; found: 134.1304.
• 13 X-ray crystallographic analysis revealed the bulky adamantyloxy groups are antiperiplanar across the Si–Si bond. See the Supporting Information for details.
• 14 Maji A, Guin S, Feng S, Dahiya A, Singh V, Liu P, Maiti D. Angew. Chem. Int. Ed. 2017; 56: 14903
• 15 We could not deny the possibility that disilane 5 reacts with Pd(II) benzoate through a concerted six-membered transition state to give silyl benzoate 15 and an Ar–Pd(II)–SiMe₂(OtBu) species, which would then generate arylsilane 6 via reductive elimination.