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(0.4 mmol, 1 equiv.), TEMPO (0.04 mmol, 0.1 equiv.) and NaIO4
(as specied in Table 4) were added to a solution of the desired
secondary amine 7–12 (0.4 mmol, 1 equiv.) in a 2 : 1 ratio of
H2O/CH3CN (10 mL) (see Table 4). Aer 20 h the mixture was
quenched with HCl 1 M and extracted with EtOAc or Et2O (3 ꢁ
10 mL). The collected organic layers were dried on anhydrous
Na2SO4, ltered and concentrated to isolate p-anisaldehyde 2a.
The aqueous phase was then basied with NaOH 1 M and
extracted with EtOAc or Et2O (3 ꢁ 10 mL). The organic layers
were dried on anhydrous Na2SO4, ltered and concentrated to
isolate amines RNH2 (1a, 1j, 1m, 1n, 1o, and 1t, see Table 4).
When specied, amines were isolated as ammonium salts in the
basic organic extract by adding one equivalent of triuoroacetic
acid (TFA) just before the nal solvent evaporation.
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General procedure for cyclic amines oxidation with sodium
periodate (GP4). In a 25 mL two-necked ask, AcOH (0.4 mmol, 10 F. Su, S. C. Mathew, L. Mohlmann, M. Antonietti, X. Wang
1 equiv., if specied in Table 5), TEMPO (0.04 mmol, 0.1 equiv.) and S. Blechert, Angew. Chem., Int. Ed., 2011, 50, 657–660.
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10 mL). The collected organic layers were dried on anhydrous 13 Z. J. Wang, S. Ghasimi, K. Landfesterand and K. A. I. Zhang,
Na2SO4, ltered and concentrated to isolate the oxidation Adv. Mater., 2015, 27, 6265–6270.
products 13, 15 (in its protonated form) or 16 (see Table 5). The 14 J. H. Ko, N. Kang, N. Park, H.-W. Shin, S. Kang, S. M. Lee,
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15 and 17 (see Table 5).
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17 H. Chen, C. Liu, M. Wang, C. Zhang, N. Luo, Y. Wang,
H. Abroshan, G. Li and F. Wang, ACS Catal., 2017, 7, 3632–
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Conflicts of interest
18 D. Lenoir, Angew. Chem., Int. Ed., 2006, 45, 3206–3210.
19 M. Largeron, Org. Biomol. Chem., 2017, 15, 4722–4730.
20 P. Galletti, M. Pori, F. Funiciello, R. Soldati, A. Ballardini and
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21 P. Galletti, F. Funiciello, R. Soldati and D. Giacomini, Adv.
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22 (a) R. Ciriminna and M. Pagliaro, Org. Process Res. Dev., 2010,
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There are no conicts to declare.
Acknowledgements
This work was supported by University of Bologna research
funding RFO 2016.
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