Mechanically induced oxidation of alcohols to aldehydes and ketones in ambient air: Revisiting TEMPO-assisted oxidations

  1. Andrea Porcheddu1,
  2. Evelina Colacino1,2,
  3. Giancarlo Cravotto3,
  4. Francesco Delogu4 and
  5. Lidia De Luca5

1Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Cagliari, Cittadella Universitaria, SS 554 bivio per Sestu, 09028 Monserrato (Ca), Italy
2Institut des Biomolécules Max Mousseron (IBMM) UMR5247 CNRS-UM-ENSCM, Université de Montpellier, Place Eugène Bataillon, cc1703, 34095 Montpellier Cedex 05, France
3Dipartimento di Scienza e Tecnologia del Farmaco, University of Turin, Via P. Giuria, 9, 10125 Turin, Italy

4Dipartimento di Ingegneria Meccanica, Chimica e dei Materiali, Università degli Studi di Cagliari, via Marengo 3, 09123 Cagliari, Italy
5Dipartimento di Chimica e Farmacia, Università degli Studi di Sassari, via Vienna 2, 07100 Sassari, Italy

  1. Corresponding author email

This article is part of the Thematic Series "Mechanochemistry".

Guest Editor: J. G. Hernández
Beilstein J. Org. Chem. 2017, 13, 2049–2055. https://doi.org/10.3762/bjoc.13.202
Received 01 Jun 2017, Accepted 28 Sep 2017, Published 02 Oct 2017

Abstract

The present work addresses the development of an eco-friendly and cost-efficient protocol for the oxidation of primary and secondary alcohols to the corresponding aldehydes and ketones by mechanical processing under air. Ball milling was shown to promote the quantitative conversion of a broad set of alcohols into carbonyl compounds with no trace of an over-oxidation to carboxylic acids. The mechanochemical reaction exhibited higher yields and rates than the classical, homogeneous, TEMPO-based oxidation.

Keywords: aldehydes; ball milling; ketones; mechanochemistry; oxidation reactions; TEMPO

Introduction

Aldehydes and ketones constitute some of the most powerful and versatile building blocks that are available for a variety of synthetic transformations [1]. The reason for this lies in the capability of the carbonyl group to generate other possible functional groups through more or less complex chemical transformations [2]. The ubiquity of the carbonyl group in biomolecules adds further value to its chemistry, which is crucial for strategic areas of science related to biochemistry and biotechnology [3,4].

In principle, the oxidation of alcohols represents a convenient option for preparing aldehydes and ketones, as alcohols are among the most abundant naturally occurring organic compounds [5,6]. Although the literature provides a plethora of generic indications and detailed recipes on this subject [7-10], the selective oxidation of primary alcohols to the corresponding aldehydes is one of the most difficult transformations to control because of the marked propensity towards over-oxidation to the respective carboxylic acid [11,12]. In addition, the appeal of this reaction is reduced by the need to use stoichiometric amounts of strong oxidising agents that are extremely toxic, hazardous, and expensive [13-17]. The use of the stable tetraalkylnitroxyl radical TEMPO (2,2,6,6-tetramethylpiperidine 1-oxyl) as the catalytic oxidising agent (Anelli–Montanari reaction) has been the main driving force behind the successful development of greener oxidation procedures [18,19]. The classic Anelli–Montanari oxidation requires aqueous NaOCl (bleach) as a co-oxidant, and it works in a CH2Cl2/H2O two-phase system buffered at pH 8.5–9.5 [20]. Over the years, bleach has been replaced with an impressively long list of other co-oxidants [21], which are sometimes very expensive, and exhibit a wide spectrum of effectiveness (Scheme 1) [22,23]. Recently, Stahl [24] developed a practical CuI/TEMPO-based catalyst for the selective oxidation of primary alcohols to aldehydes under ambient aerobic conditions (Scheme 1) [25,26]. The procedure is operationally simple and extremely effective in terms of both chemoselectivity and reaction yield [27,28]. Gao (2016) further improved this methodology by replacing the bpy/CuI/NMI catalyst system with Fe(NO3)3·9H2O, a cheaper, ligand-free co-oxidant (Scheme 1) [29,30]. This made the oxidative process more appealing for pharmaceutical applications, and specifically beneficial in the preparation of fragrances and food additives [31].

[1860-5397-13-202-i1]

Scheme 1: TEMPO-catalysed aerobic oxidative procedures of alcohols. a) Anelli–Montanari protocol: NaOCl (1.25 mol equiv), TEMPO (1–2 mol %), KBr (10 mol %), NaHCO3 (pH 8.6), CH2Cl2/H2O. b) Stahl protocol: [Cu(MeCN)4](OTf) (5 mol %), bpy (5 mol %), TEMPO (5 mol %), NMI (10 mol %), CH3CN, air. c) Gao (2016) protocol: Fe(NO)3.9H2O (10 mol %), 9-azabicyclo[3.3.1]nonan-N-oxyl (ABNO, 1–3 mol %), CH3CN, air.

Despite the advances, the choice of solvent for TEMPO-based oxidative procedures remains a crucial issue in the development of greener alternatives to traditional alcohol oxidation reactions [32-34]. In particular, the lack of a green option significantly decreases the attractiveness of the proposed synthetic routes, as the solvent is the main component of the reaction system and, thus, the main source of waste in organic synthesis [35]. By far, performing the oxidation of alcohols under solvent-free conditions represents the best strategy to radically eliminate possible drawbacks in regard to waste disposal [36,37]. In this respect, the mechanical activation of solids [38-42], in the absence of solvents [43], or in the presence of catalytic amounts of liquid [44,45], holds significant promise [46-58].

Rooted in ancient practices from the dawn of civilization, a thin historical thread twisting across human history connects powder metallurgy and mineralurgy with science and engineering at the cutting edge of research in the fields of materials science and chemistry [59]. Presently, mechanochemistry is one of the fastest growing areas of investigation that aims to provide alternative methods to traditional syntheses in organic and inorganic chemistry [49,60,61]. Mechanochemistry is also used in supramolecular chemistry [62] and metal-organic chemistry [63].

In this work, we show that mechanical processing by ball milling can represent a viable solution to the selective oxidation of alcohols to aldehydes. Specifically, we investigated the potential of a mechanically activated TEMPO-based oxidative procedure [64].

Results and Discussion

We began our investigation with an attempt to replicate Gao’s procedure in a stainless steel reactor of a commercial ball mill in the presence of stainless steel balls and air, and in the absence of solvent. The oxidation of solid 4-nitrobenzyl alcohol (1a) to 4-nitrobenzaldehyde (2a) was selected as a model reaction. Unfortunately, the alcohol-to-aldehyde conversion was very low (<15%), and the use of larger amounts of the catalyst as well as molecular oxygen instead of air did not result in a significant improvement (Scheme 2, left side). To our great surprise, using Stahl’s catalyst, the mechanically activated oxidation of the model substrate 1a under solvent-free conditions proceed so quickly and selectively that it was complete within just a few minutes. The progress of the reaction was monitored by TLC and GC–MS analysis until the completion of the reaction. The experimental protocol involved two stages, namely the preparation of the catalytic system and the final oxidation reaction. During the first stage [Cu(MeCN)4]OTf (5 mol %), 2,2′-bipyridine (5 mol %), NMI (10 mol %), and TEMPO (5 mol %) were milled (1 min) in a stainless steel reactor using four stainless steel balls of different sizes. Following the mechanical treatment, the catalyst uniformly covered the reactor walls forming a dark red/brown thin film. Subsequently, solid 4-nitrobenzyl alcohol (1a, 2 mmol) was added together with two more stainless steel balls (12 mm Ø), and the resulting mixture was milled until the starting alcohol was completely oxidized. Despite the poor reactivity of the 4-nitrobenzyl alcohol, the reaction smoothly reached completion in only 14 minutes (two cycles of 7 minutes each). GC–MS analysis of the crude reaction mixture only showed the presence of the desired aromatic aldehyde, indicating that over-oxidation did not occur (Scheme 2, right side). Prolonged milling did not result in the formation of detectable amounts of the carboxylic acid.

[1860-5397-13-202-i2]

Scheme 2: TEMPO-assisted oxidation of 4-nitrobenzylic alcohol under mechanical activation conditions [65].

Next, we replaced the starting stainless-steel grinding jar and balls with a zirconia jar (45 mL) and six zirconium oxide balls (5 and 12 mm Ø) with the aim of avoiding contamination due to metal release. Under these conditions, it was possible to reduce the loading of [Cu(MeCN)4]OTf, 2,2′-bipyridine and TEMPO to 3 mol % and NMI loading to 7 mol % without affecting the reaction time or the product yield. Interestingly, the alcohol-to-aldehyde oxidation under ball milling conditions was faster (15 min overall) than that in solution (1 h) [25]. In addition, the absence of a solvent facilitated the purification of the final aldehyde. Specifically, the reaction crude was transferred from the reactor into a beaker containing an aqueous 10% citric acid solution [66,67], and the desired product precipitated as a solid. If necessary, the crude product could be further purified via filtering on a short pad of silica gel to give final aldehyde 2a with a higher degree of purity (>95% as determined by GC–MS analysis). Since most common alcohols are, unfortunately, liquids at room temperature, their mechanical activation requires using a versatile dispersant. Ideally, a dispersant should not interfere with the oxidation reaction, and should be inexpensive and eco-friendly, if possible. As a first choice, we dispersed benzyl alcohol (1b) on alumina and silica gel. However, the reaction did not go to completion. In contrast, it proceeded smoothly (10 min) and in high yields when Na2SO4 and NaCl [68] were used as dispersants. Furthermore, the use of sodium chloride (500 mg per mmol of alcohol) facilitated the transfer of the reaction mixture from the reactor to the separating funnel containing the aqueous 10% citric acid solution. On the microscale (2 mmol), the full recovery of benzaldehyde was only achieved after solvent extraction. A minor modification to the synthetic protocol, involving the use of additional zirconia balls (four balls × 5 mm Ø, 7 balls × 12 mm Ø) and opening the jar (3 min) to air during the time interval between two consecutive cycles, gave 2b in 96% overall yield even on the gram scale. On the gram scale, the mechanical activation no longer required an additional solvent to recover the final aldehyde during purification. With the optimized reaction conditions in hand, a series of common benzyl alcohols 1b–n with different functional groups was then tested in order to examine the scope of the reaction (Scheme 3). To our satisfaction, very high yields (>90%) were obtained with all tested compounds, except 2n (39%).

[1860-5397-13-202-i3]

Scheme 3: Scope of primary alcohols in oxidation under ambient air.

Benzyl alcohols containing alkyl or aryl groups on the aromatic ring were all transformed into the desired products in quantitative or nearly quantitative isolated yields (compounds 2c–f in Scheme 3). The position of the hydrocarbon (–R) on the ring did not significantly affect the aldehyde yield (aldehydes 2c–e in Scheme 3). Substrates bearing electron-donating and electron-withdrawing functional groups on the aromatic ring of the benzyl alcohol were also viable, giving the corresponding aromatic aldehydes in high yields regardless of the electronic nature of their substituents (aldehydes 2g–k in Scheme 3). Surprisingly, and contrary to Stahl’s original solution procedure [24], the oxidation of 2-hydroxybenzyl alcohol under mechanical activation conditions provided the salicylaldehyde in nearly quantitative yield (compound 2k in Scheme 3). The reaction was also successfully expanded to heteroaromatic alcohol 1l (Scheme 3, 2-furylmethanol), giving furfural in a very good yield (90%). The mechanically induced oxidative procedure was also applied to allylic alcohol derivatives. Cinnamyl alcohol (1m) was transformed into the corresponding α,β-unsaturated aldehyde in an excellent yield (96%) and with the stereochemical retention of the double bond. Encouraged by these promising results, we attempted to oxidise alkynols to the corresponding propargylic aldehyde derivatives, which were not previously accessible via classical homogeneous phase methods [25]. Contrary to our expectations, the ball milling protocol proved to be an efficient approach for the synthesis of these substrates, giving phenylpropargylaldehyde (2n) in a modest yield (39%) after 4 cycles (15 min per cycle). Unfortunately, prolonged milling times led to the decomposition of the final aldehyde. These promising results prompted us to undertake additional studies on secondary alcohols. The optimised ball milling protocol was applied to alcohols 1o–v. Excellent yields of the ketones 2o–v were obtained (Scheme 4). Notably, the product yield was not significantly affected by the position or electronic nature of the substituents on the aromatic ring of the alcohols.

[1860-5397-13-202-i4]

Scheme 4: Scope of secondary alcohols in oxidation under ambient air.

Encouraged by the facile oxidation of benzyl alcohols, the scope of the reaction was finally extended to the formation of more challenging aliphatic aldehydes. Unfortunately, non-activated aliphatic alcohols did not react efficiently under the reaction conditions, and very low alcohol-to-aldehyde conversions occurred. The extension of milling times to 3 h failed to result in improved yields of all tested substrates: 3-phenyl-1-propanol, cyclohexanol and nonanol. Despite several attempts to improve the alcohol-to-aldehyde conversion, by, for instance, milling under an oxygen atmosphere and the use of more reactive co-oxidant catalysts [69], no significant improvements were observed.

Conclusion

We have developed a TEMPO-based oxidative procedure for the air oxidation of primary and secondary benzyl alcohols to the corresponding aldehydes and ketones under ball milling conditions. A library of common alcohols was efficiently converted into carbonyl compounds with no trace of over-oxidation to the carboxylic acids. The final products could be easily separated/purified from the crude reaction mixture without using toxic organic solvents. Under mechanical activation conditions, the reactions provided better yields and proceeded faster than classical, homogeneous phase TEMPO-based oxidations. Studies are underway to identify more effective TEMPO-based catalysts that are also capable of promoting the oxidation of non-activated alcohols.

Experimental

General procedure to prepare carbonyl compounds 2a–v. 2,2,6,6-Tetramethylpiperidine 1-oxyl (TEMPO, 9.4 mg, 0.06 mmol, 3 mol %), 2,2′-bipyridyl (9,4 mg, 0.06 mmol, 3 mol %), [Cu(CN)4]OTf (22.6 mg, 0.06 mmol, 3 mol %) and 1-methylimidazole (NMI, 11.5 mg, 11.2 μL, 0.14 mmol, 7 mol %) were placed in a zirconia-milling beaker (45 mL) equipped with four balls (two balls × 5 mm Ø, two balls × 12 mm Ø) of the same material. The jar was sealed and ball-milled for 1 min. Then, benzyl alcohol (216.3 mg, 207 μL, 2.0 mmol), NaCl (1.0 g) together with other two zirconia balls (12 mm Ø) were added and the reaction mixture was subjected to grinding for further 10 minutes overall (two cycles of 5 minutes each). The first milling cycle was followed by a break of 2 min leaving in the meantime the uncovered jar in open air. The progress of the reaction was monitored by TLC analysis (heptane/AcOEt 9:1 v/v) and GC–MS analysis on an aliquot of the crude. Upon completion of the ball milling process, the jar was opened, the milling balls were removed and the resulting crude product (adsorbed on NaCl) was then easily transferred into a separating funnel filled with an aqueous 10% citric acid solution (20 mL). The aqueous phase was extracted with cyclopentyl methyl ether (or alternatively with AcOEt) (3 × 15 mL). The combined organic fractions were washed with H2O (25 mL) and brine (25 mL), then dried over Na2SO4, and concentrated in vacuo to give benzaldehyde in high yield (195 mg, 92%) and good purity (>93% by GC analysis). Alternatively, after completion of the reaction, the resulting crude product (adsorbed on NaCl) can be also easily purified by a short column chromatography on silica gel using heptane/ethyl acetate (9:1 v/v) as the eluents to afford pure aldehyde 2b in high yield (202 mg, 95%) as a colourless liquid.

Supporting Information

Supporting Information File 1: Experimental part and NMR spectra.
Format: PDF Size: 1.5 MB Download

Acknowledgements

This work was financially supported by RAS within the projects: a) “Valorizzazione di biomasse d’interesse regionale attraverso processi chimici a basso impatto ambientale” (CRP 72-Bando “Capitale Umano ad Alta Qualificazione. Annualità 2015_L.R. 7 agosto 2007, n°7”), b) “Smart Nanostructured Functional Materials: Synthesis and Characterization with Focus on the Specific Interactions between Solid Surfaces and Biomacromolecules“ (RICALTRO_CTC_2017_RAS_MONDUZZI) and by Fondazione Banco di Sardegna with the projects: RICALTRO_CTC_2017_FBS_MONDUZZI. The “Teach Mob – Teaching Staff Mobility Programme 2016-2017” (University of Turin) is warmly acknowledged by EC and GC. E.C. is grateful to the Università degli Studi di Cagliari (Italy) (Visiting Professor Program 2016-2017) for the grant.

References

  1. Dubrovskiy, A. V.; Kesharwani, T.; Markina, N. A.; Pletnev, A. A.; Raminelli, C.; Yao, T.; Zeni, G.; Zhang, L.; Zhang, X.; Rozhkov, R.; Larock, R. C., Eds. Comprehensive Organic Transformations: A Guide to Functional Group Preparations, 3rd ed.; Wiley: New York, 2017.
    Return to citation in text: [1]
  2. Smith, B. H. March's Advanced Organic Chemistry: Reactions, Mechanisms, and Structure, 7th ed.; John Wiley & Sons: New York, 2013.
    Return to citation in text: [1]
  3. Nicolaou, K. C.; Sorensen, E. J. Classics in Total Synthesis: Targets, Strategies, Methods; Wiley-VCH: Weinheim, 1996.
    Return to citation in text: [1]
  4. Warren, S. Chemistry of the Carbonyl Group: A Programmed Approach to Organic Reaction Mechanism; John Wiley & Sons: New York, 1974.
    Return to citation in text: [1]
  5. Tojo, G.; Fernandez, M. Oxidations of Alcohols to Aldehydes and Ketones -A Guide to Current Common Practice; Springer: New York, 2006.
    Return to citation in text: [1]
  6. Hudlucky, M. Oxidations in Organic Chemistry; ACS Monograph Series; American Chemical Society: Washington, DC, 1990.
    Return to citation in text: [1]
  7. Mancuso, A. J.; Huang, S.-L.; Swern, D. J. Org. Chem. 1978, 43, 2480–2482. doi:10.1021/jo00406a041
    Return to citation in text: [1]
  8. Dess, D. B.; Martin, J. C. J. Org. Chem. 1983, 48, 4155–4156. doi:10.1021/jo00170a070
    Return to citation in text: [1]
  9. Ley, S. V.; Norman, J.; Griffith, W. P.; Marsden, S. P. Synthesis 1994, 639–666. doi:10.1055/s-1994-25538
    Return to citation in text: [1]
  10. Baxendale, I. R.; Deeley, J.; Griffiths-Jones, C. M.; Ley, S. V.; Saaby, S.; Tranmer, G. K. Chem. Commun. 2006, 2566–2568. doi:10.1039/B600382F
    Return to citation in text: [1]
  11. Arends, I. W. C. E.; Sheldon, R. A.; Bäckvall, J. E., Eds. Modern Oxidation Methods, 2nd ed.; Wiley-VCH: Weinheim, 2011.
    Return to citation in text: [1]
  12. Boisvert, L.; Goldberg, K. I. Acc. Chem. Res. 2012, 45, 899–910. doi:10.1021/ar2003072
    Return to citation in text: [1]
  13. Luzzio, F. A.; Guziec, F. S., Jr. Org. Prep. Proced. Int. 1988, 20, 533–584. doi:10.1080/00304948809356301
    Return to citation in text: [1]
  14. Fatiadi, A. J. Synthesis 1976, 65–104. doi:10.1055/s-1976-23961
    Return to citation in text: [1]
  15. Tidwell, T. T. Synthesis 1990, 857–870. doi:10.1055/s-1990-27036
    Return to citation in text: [1]
  16. Sheldon, R. A.; Arends, I. W. C. E.; ten Brink, G.-J.; Dijksman, A. Acc. Chem. Res. 2002, 35, 774–781. doi:10.1021/ar010075n
    Return to citation in text: [1]
  17. Tohma, H.; Kita, Y. Adv. Synth. Catal. 2004, 346, 111–124. doi:10.1002/adsc.200303203
    Return to citation in text: [1]
  18. Cella, J. A.; Kelley, J. A.; Kenehan, E. F. J. Org. Chem. 1975, 40, 1860–1862. doi:10.1021/jo00900a049
    Return to citation in text: [1]
  19. Ganem, B. J. Org. Chem. 1975, 40, 1998–2000. doi:10.1021/jo00901a030
    Return to citation in text: [1]
  20. Anelli, P. L.; Biffi, C.; Montanari, F.; Quici, S. J. Org. Chem. 1987, 52, 2559–2562. doi:10.1021/jo00388a038
    Return to citation in text: [1]
  21. De Luca, L.; Giacomelli, G.; Porcheddu, A. Org. Lett. 2001, 3, 3041–3043. doi:10.1021/ol016501m
    Return to citation in text: [1]
  22. Bolm, C.; Magnus, A. S.; Hildebrand, J. P. Org. Lett. 2000, 2, 1173–1175. doi:10.1021/ol005792g
    Return to citation in text: [1]
  23. Markó, I. E.; Giles, P. R.; Tsukazaki, M.; Brown, S. M.; Urch, C. J. Science 1996, 274, 2044–2046. doi:10.1126/science.274.5295.2044
    Return to citation in text: [1]
  24. Hoover, J. M.; Steves, J. E.; Stahl, S. S. Nat. Protoc. 2012, 7, 1161–1167. doi:10.1038/nprot.2012.057
    Return to citation in text: [1] [2]
  25. Hoover, J. M.; Ryland, B. L.; Stahl, S. S. J. Am. Chem. Soc. 2013, 135, 2357–2367. doi:10.1021/ja3117203
    Return to citation in text: [1] [2] [3]
  26. Könning, D.; Olbrisch, T.; Sypaseuth, F. D.; Tzschucke, C. C.; Christmann, M. Chem. Commun. 2014, 50, 5014–5016. doi:10.1039/C4CC01305K
    Return to citation in text: [1]
  27. Ryland, B. L.; Stahl, S. S. Angew. Chem., Int. Ed. 2014, 53, 8824–8838. doi:10.1002/anie.201403110
    and references cited therein.
    Return to citation in text: [1]
  28. Allen, S. E.; Walvoord, R. R.; Padilla-Salinas, R.; Kozlowski, M. C. Chem. Rev. 2013, 113, 6234–6458. doi:10.1021/cr300527g
    Return to citation in text: [1]
  29. Wang, L.; Shang, S. S.; Li, G.; Ren, L.; Lv, Y.; Gao, S. J. Org. Chem. 2016, 81, 2189–2193. doi:10.1021/acs.joc.6b00009
    Return to citation in text: [1]
  30. Ma, S.; Liu, J.; Li, S.; Chen, B.; Cheng, J.; Kuang, J.; Liu, Y.; Wan, B.; Wang, Y.; Ye, Y.; Yu, Q.; Yuan, W.; Yu, S. Adv. Synth. Catal. 2011, 353, 1005–1017. doi:10.1002/adsc.201100033
    Return to citation in text: [1]
  31. Alfonsi, K.; Colberg, J.; Dunn, P. J.; Fevig, T.; Jennings, S.; Johnson, T. A.; Kleine, H. P.; Knight, C.; Nagy, M. A.; Perry, D. A.; Stefaniak, M. Green Chem. 2008, 10, 31–36. doi:10.1039/B711717E
    Return to citation in text: [1]
  32. Cao, Q.; Dornan, L. M.; Rogan, L.; Hughes, N. L.; Muldoon, M. J. Chem. Commun. 2014, 50, 4524–4543. doi:10.1039/C3CC47081D
    Return to citation in text: [1]
  33. Sheldon, R. A. Chem. Soc. Rev. 2012, 41, 1437–1451. doi:10.1039/c1cs15219j
    Acetonitrile is considered by the US Environmental Protection Agency as a hazardous solvent that produces acute systemic and potentially carcinogenic effects.
    Return to citation in text: [1]
  34. Trost, B. M. Science 1991, 254, 1471–1477. doi:10.1126/science.1962206
    Return to citation in text: [1]
  35. Parmeggiani, C.; Cardona, F. Green Chem. 2012, 14, 547–564. doi:10.1039/C2GC16344F
    Return to citation in text: [1]
  36. Rothenberg, G.; Downie, A. P.; Raston, C. L.; Scott, J. L. J. Am. Chem. Soc. 2001, 123, 8701–8708. doi:10.1021/ja0034388
    Return to citation in text: [1]
  37. Hernández, J. G.; Juaristi, E. J. Org. Chem. 2010, 75, 7107–7111. doi:10.1021/jo101159a
    Return to citation in text: [1]
  38. Tabasso, S.; Carnaroglio, D.; Calcio Gaudino, E.; Cravotto, G. Green Chem. 2015, 17, 684–693. doi:10.1039/C4GC01545B
    Return to citation in text: [1]
  39. Eagling, R., Ed. Mechanochemistry: From Functional Solids to Single Molecule; Faraday Discussions of the Chemical Society, Vol. 170; Royal Society of Chemistry: Cambridge, UK, 2014.
    Return to citation in text: [1]
  40. Humphry-Baker, S. A.; Garroni, S.; Delogu, F.; Schuh, C. A. Nat. Mater. 2016, 15, 1280–1286. doi:10.1038/nmat4732
    Return to citation in text: [1]
  41. Cravotto, G.; Calcio Gaudino, E. Oxidation and reduction by solid oxidants and reducing agents using ball milling. In Ball Milling Towards Green Synthesis: Applications, Projects, Challenges; Ranu, B. C.; Stolle, A., Eds.; Royal Society of Chemistry: Cambridge, UK, 2014.
    Return to citation in text: [1]
  42. James, S. L.; Adams, C. J.; Bolm, C.; Braga, D.; Collier, P.; Friščić, T.; Grepioni, F.; Harris, K. D. M.; Hyett, G.; Jones, W.; Krebs, A.; Mack, J.; Maini, L.; Orpen, A. G.; Parkin, I. P.; Shearouse, W. C.; Steed, J. W.; Waddell, D. C. Chem. Soc. Rev. 2012, 41, 413–447. doi:10.1039/C1CS15171A
    Return to citation in text: [1]
  43. Margetic, D.; Štrukil, V. Mechanochemical Organic Synthesis; Elselvier: Amsterdam, 2016.
    Return to citation in text: [1]
  44. Friščić, T.; Childs, S. L.; Rizvi, S. A. A.; Jones, W. CrystEngComm 2009, 11, 418–426. doi:10.1039/B815174A
    Return to citation in text: [1]
  45. Hasa, D.; Miniussi, E.; Jones, W. Cryst. Growth Des. 2016, 16, 4582–4588. doi:10.1021/acs.cgd.6b00682
    Return to citation in text: [1]
  46. Rodriguez, B.; Bruckmann, A.; Rantanen, T.; Bolm, C. Adv. Synth. Catal. 2007, 349, 2213–2233. doi:10.1002/adsc.200700252
    Return to citation in text: [1]
  47. Stolle, A.; Szuppa, T.; Leonhardt, S. E. S.; Ondruschka, B. Chem. Soc. Rev. 2011, 40, 2317–2329. doi:10.1039/c0cs00195c
    Return to citation in text: [1]
  48. Tan, D.; Loots, L.; Friščić, T. Chem. Commun. 2016, 52, 7760–7781. doi:10.1039/C6CC02015A
    Return to citation in text: [1]
  49. Wang, G.-W. Chem. Soc. Rev. 2013, 42, 7668–7700. doi:10.1039/C3CS35526H
    Return to citation in text: [1] [2]
  50. Cravotto, G.; Garella, D.; Carnaroglio, D.; Calcio Gaudino, E.; Rosati, O. Chem. Commun. 2012, 48, 11632–11634. doi:10.1039/c2cc36365h
    Return to citation in text: [1]
  51. Stolle, A.; Ranu, B., Eds. Ball Milling Towards Green Synthesis: Applications, Projects, Challenges; The Royal Society of Chemistry: Cambridge, 2015.
    Return to citation in text: [1]
  52. Hernández, J. G.; Friščić, T. Tetrahedron Lett. 2015, 56, 4253–4265. doi:10.1016/j.tetlet.2015.03.135
    Return to citation in text: [1]
  53. Machuca, E.; Juaristi, E.; Brindaban, R.; Stolle, A. Asymmetric Organocatalytic Reactions Under Ball Milling. Ball Milling Towards Green Synthesis: Applications, Projects, Challenges; Royal Society of Chemistry: Cambridge, UK, 2015; pp 81–95.
    Return to citation in text: [1]
  54. Hernández, J. G.; Frings, M.; Bolm, C. ChemCatChem 2016, 8, 1769–1772. doi:10.1002/cctc.201600455
    Return to citation in text: [1]
  55. Mocci, R.; De Luca, L.; Delogu, F.; Porcheddu, A. Adv. Synth. Catal. 2016, 358, 3135–3144. doi:10.1002/adsc.201600350
    Return to citation in text: [1]
  56. Gaspa, S.; Porcheddu, A.; Valentoni, A.; Garroni, S.; Enzo, S.; De Luca, L. Eur. J. Org. Chem. 2017. doi:10.1002/ejoc.201700689
    Return to citation in text: [1]
  57. Hernández, J. G.; Bolm, C. J. Org. Chem. 2017, 82, 4007–4019. doi:10.1021/acs.joc.6b02887
    Return to citation in text: [1]
  58. Do, J.-L.; Friščić, T. ACS Cent. Sci. 2017, 3, 13–19. doi:10.1021/acscentsci.6b00277
    Return to citation in text: [1]
  59. Takacs, L. Chem. Soc. Rev. 2013, 42, 7649–7659. doi:10.1039/c2cs35442j
    Return to citation in text: [1]
  60. Boldyreva, E. Chem. Soc. Rev. 2013, 42, 7719–7738. doi:10.1039/C3CS60052A
    Return to citation in text: [1]
  61. Baláž, P.; Achimovičová, M.; Baláž, M.; Billik, P.; Cherkezova-Zheleva, Z.; Criado, J. M.; Delogu, F.; Dutková, E.; Gaffet, E.; Gotor, F. J.; Kumar, R.; Mitov, I.; Rojac, T.; Senna, M.; Streletskii, A.; Wieczorek-Ciurowa, K. Chem. Soc. Rev. 2013, 42, 7571–7637. doi:10.1039/c3cs35468g
    Return to citation in text: [1]
  62. Friščić, T.; Jones, W. Cryst. Growth Des. 2009, 9, 1621–1637. doi:10.1021/cg800764n
    Return to citation in text: [1]
  63. Friščić, T. Chem. Soc. Rev. 2012, 41, 3493–3510. doi:10.1039/c2cs15332g
    Return to citation in text: [1]
  64. Sahoo, P. K.; Bose, A.; Mal, P. Eur. J. Org. Chem. 2015, 6994–6998. doi:10.1002/ejoc.201501039
    In 2015, Mal et al. reported the first example of a very interesting solvent free ball-milling oxidation of activated primary alcohols to aldehyde using NBS (1.5 equiv) or oxone (0.6 equiv) as co-oxidising agents. This paper has laid the foundation for further studies on this topic.
    Return to citation in text: [1]
  65. Rightmire, N. R.; Hanusa, T. P. Dalton Trans. 2016, 45, 2352–2362. doi:10.1039/C5DT03866A
    The formalism for mechanochemically activated reactions was proposed here.
    Return to citation in text: [1]
  66. Lanzillotto, M.; Konnert, L.; Lamaty, F.; Martinez, J.; Colacino, E. ACS Sustainable Chem. Eng. 2015, 3, 2882–2889. doi:10.1021/acssuschemeng.5b00819
    Return to citation in text: [1]
  67. Konnert, L.; Lamaty, F.; Martinez, J.; Colacino, E. J. Org. Chem. 2014, 79, 4008–4017. doi:10.1021/jo500463y
    Return to citation in text: [1]
  68. Konnert, L.; Gauliard, A.; Lamaty, F.; Martinez, J.; Colacino, E. ACS Sustainable Chem. Eng. 2013, 1, 1186–1191. doi:10.1021/sc4001115
    Return to citation in text: [1]
  69. Rogan, L.; Hughes, N. L.; Cao, Q.; Dornan, L. M.; Muldoon, M. J. Catal. Sci. Technol. 2014, 4, 1720–1725. doi:10.1039/C4CY00219A
    Return to citation in text: [1]

© 2017 Porcheddu et al.; licensee Beilstein-Institut.
This is an Open Access article under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The license is subject to the Beilstein Journal of Organic Chemistry terms and conditions: (http://www.beilstein-journals.org/bjoc)

 
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