Mechanochemical Synthesis of Diarylethynes from Aryl Iodides and CaC₂

Abstract

A mechanochemical synthesis of diarylethynes from aryl iodides and calcium carbide as acetylene source is reported. The reaction is catalyzed by a palladium catalyst in the presence of copper salt, base, and ethanol as liquid assisting grinding (LAG) additive. Various aryl and heteroaryl iodides have been converted in up to excellent yields.

Key words

mechanochemistry - calcium carbide - ball milling - diaryl­ethyne - catalysis - palladium

Publikationsverlauf

Eingereicht: 09. November 2021

Angenommen nach Revision: 07. Januar 2022

Accepted Manuscript online:
07. Januar 2022

Artikel online veröffentlicht:
10. Februar 2022

• References and Notes

• 1a Ostwald W. Lehrbuch der Allgemeinen Chemie . Engelmann; Leipzig: 1887
• 1b Ostwald W. Handbuch der Allgemeinen Chemie . Akademische Verlagsgesellschaft; Leipzig: 1919
• 2a James SL, Adams CJ, Bolm C, Braga D, Collier P, Friščić T, Grepioni F, Harris KD. M, Hyett G, Jones W, Krebs A, Mack J, Maini L, Orpen AG, Parkin IP, Shearouse WC, Steed JW, Waddell DC. Chem. Soc. Rev. 2012; 41: 413
• 2b Do J.-L, Friščić T. ACS Cent. Sci. 2017; 3: 13
• 2c Howard JL, Cao Q, Browne DL. Chem. Sci. 2018; 9: 3080
• 2d Friščić T, Mottillo C, Titi HM. Angew. Chem. Int. Ed. 2020; 59: 1018
• 2e Pickhardt W, Grätz S, Borchardt L. Chem. Eur. J. 2020; 26: 12903
• 2f Ardila-Fierro KJ, Hernández JG. ChemSusChem 2021; 14: 2145
• 2g Hernandez JG, Bolm C. J. Org. Chem. 2017; 82: 4007
• 2h Porcheddu A, Colacino E, De Luca L, Delogu F. ACS Catal. 2020; 10: 8344
• 2i Zhu S.-E, Li F, Wang G.-W. Chem. Soc. Rev. 2013; 42: 7535
• 2j Wang GW. Chin. J. Chem. 2021; 39: 1797
• 2k Kaiser RP, Krake EF, Backer L, Urlaub J, Baumann W, Handler N, Buschmann H, Beweries T, Holzgrabe U, Bolm C. Chem. Commun. 2021; 57: 11956
• 3 Kubota K, Ito H. Trends Chem. 2020; 2: 1066
• 4 Fulmer DA, Shearouse WC, Medonza ST, Mack J. Green Chem. 2009; 11: 1821
• 5 Thorwirth R, Stolle A, Ondruschka B. Green Chem. 2010; 12: 985
• 6a Deng D, Huang D, Sun X, Gao B. Synthesis 2021; 53: 3522
• 6b Mei H, Yin Z, Liu J, Sun H, Han J. Chin. J. Chem. 2019; 37: 292
• 6c Koike T, Akita M. Acc. Chem. Res. 2016; 49: 1937
• 6d Shimizu Y, Kanai M. Tetrahedron Lett. 2014; 55: 3727
• 6e Huang M.-H, Hao W.-J, Li G, Tu S.-J, Jiang B. Chem. Commun. 2018; 54: 10791
• 7a Sonogashira K, Tohda Y, Hagihara N. Tetrahedron Lett. 1975; 4467
• 7b Pal M, Kundu NG. J. Chem. Soc., Perkin Trans. 1 1996; 449
• 7c Li C.-J, Chen D.-L, Costello CW. Org. Process Res. Dev. 1997; 1: 325
• 8 For a general review on the use of acetylene, see: Trotus I.-T, Zimmermann T, Schüth F. Chem. Rev. 2014; 114: 1761
• 9a Rodygin KS, Ledovskaya MS, Voronin VV, Lotsman KA, Ananikov VP. Eur. J. Org. Chem. 2021; 43
• 9b Voronin VV, Ledovskaya MS, Bogachenkov AS, Rodygin KS, Ananikov VP. Molecules 2018; 23: 2442
• 9c Rodygin KS, Werner G, Kucherov FA, Ananikov VP. Chem. Asian J. 2016; 11: 965
• 10 Zhang W, Wu H, Liu Z, Zhong P, Zhang L, Huang X, Cheng J. Chem. Commun. 2006; 4826
• 11a Chuentragool P, Vongnam K, Rashatasakhon P, Sukwattanasinitt M, Wacharasindhu S. Tetrahedron 2011; 67: 8177
• 11b Thavornsin N, Sukwattanasinitt M, Wacharasindhu S. Polym. Chem. 2014; 5: 48
• 11c Matake R, Niwa Y, Matsubara H. Org. Lett. 2015; 17: 2354
• 11d Fu R, Li Z. Eur. J. Org. Chem. 2017; 6648
• 11e Hosseini A, Pilevar A, Hogan E, Mogwitz B, Schulze AS, Schreiner PR. Org. Biomol. Chem. 2017; 15: 6800
• 11f Li Z, Ma X. Synlett 2021; 32: 631
• 12a Turberg M, Ardila-Fierro KJ, Bolm C, Hernandez JG. Angew. Chem. Int. Ed. 2018; 57: 10718
• 12b Li A, Song H, Xu X, Meng H, Lu Y, Li C. ACS Sustainable Chem. Eng. 2018; 6: 9560
• 12c Ardila-Fierro KJ, Bolm C, Hernandez JG. Angew. Chem. Int. Ed. 2019; 58: 12945
• 12d Casco ME, Kirchhoff S, Leistenschneider D, Rauche M, Brunner E, Borchardt L. Nanoscale 2019; 11: 4712
• 12e Hosseini A, Schreiner PR. Eur. J. Org. Chem. 2020; 4339
• 12f Li Y, Li S, Xu X, Gu J, He X, Meng H, Lu Y, Li C. ACS Sustainable Chem. Eng. 2021; 9: 9221

For recent reviews on liquid-assisted grinding (LAG), see:
• 13a Ying P, Yu J, Su W. Adv. Synth. Catal. 2021; 363: 1246
• 13b Bowmaker GA. Chem. Commun. 2013; 49: 334
• 13c Friščić T, Childs SL, Rizvi SA. A, Jones W. CrystEngComm 2009; 11: 418
• 14 1,2-Di-p-tolylethyne (2a); Procedure: A stainless steel milling jar (volume: 5 mL) equipped with one stainless steel milling ball (diameter: 10 mm) was loaded with Pd(OAc)₂ (2.3 mg, 0.01 mmol, 5 mol%), PPh₃ (5.3 mg, 0.02 mmol, 10 mol%), CuI (3.8 mg, 0.02 mmol, 10 mol%), K₂CO₃ (55.3 mg, 0.4 mmol, 2.0 equiv) and iodo-4-methylbenzene (87.2 mg, 0.4 mmol, 2.0 equiv). The jar was brought inside a glovebox and CaC₂ [25.6 mg, 0.4 mmol, 2.0 equiv of technical grade CaC₂ (75.54% purity), real amount added 0.30 mmol] and ethanol (45 μL) were added. The jar was closed tightly under argon atmosphere using Teflon tape for the thread and additional Parafilm was wrapped around the closed jar. After 90 min at 30 Hz the jar was opened in air, the product was extracted with ethyl acetate (5 × 3 mL) and evaporated on silica. The product was purified by flash column chromatography on silica gel [n-pentane; R_f 0.39 (n-pentane)] to give 1,2-di-p-tolylethyne (40.1 mg, 0.194 mmol, 97%) as a pale-yellow solid. ¹H NMR (600 MHz, CDCl₃): δ = 7.43 (d, J = 8.1 Hz, 4 H), 7.16 (d, J = 7.8 Hz, 4 H), 2.38 (s, 6 H) ppm. ¹³C{¹H} NMR (151 MHz, CDCl₃): δ = 138.3, 131.6, 129.2, 120.5, 89.0, 21.6 ppm. The analytic data is consistent with reported data (ref. 11f).
• 15 When the typical procedure (see ref. 14) was modified by not using the glovebox and adding freshly ground CaC₂ and ethanol in air followed by flushing the jar with argon, 2a was obtained in only 80% yield (as determined by ¹H NMR spectroscopy). Most likely, the moisture sensitivity of CaC₂ and a partial evaporation of ethanol were responsible for this decrease in yield. Also in this case, 2a′ remained undetected.
• 16 Besides 2i (44% yield), 22% of aryl iodide 1i could be isolated. After the unsuccessful attempt to couple 1-iodonaphthalene, the starting material was recovered in 58%. Except when detailed, no mono-aryl alkynes were observed in any of the couplings.
• 17 After our submission, Ito, Kubota, and co-workers reported a mechanochemical Sonogashira cross-coupling of aryl bromides and chlorides with triisopropylsilyl acetylene and aryl acetylenes under high-temperature ball-milling conditions. The protocol expands the scope of the mechanochemical Sonogashira cross-couplings developed by Mack and Stolle and highlights the benefits of ball milling compared to solution-based reactions of poorly soluble substrates. See: Gao Y, Feng C, Seo T, Kubota K, Ito H. Chem. Sci. 2021; 13: 430