Imidazole → (4-Nitro-benzyl) t-butyl-di-phenyl-silyl ether

Beteiligte Stoffe

Reaktionsschritte

To a stirred solution of 4-nitrobenzyl alcohol, 12, (1.00 g, 6.50 mmol), and imidazole (0.97 g, 14.1 mmol) in DMF (10.0 ml), was added tert-butyl-diphenyl-chlorosilane (1.98 g, 7.20 mmol) over 10 min under N2 at room temperature. The reaction mixture was stirred for an additional 5 h, diluted with Et2O (75 ml), washed with H2O (5×15 ml), dried (MgSO4) and evaporated to dryness under vacuum. An oil was obtained which crystallised on standing and was recrystallised to a solid from EtOH (70%); yield: 2.36 g (93%). vmax /cm-1 (film): 2931, 2857 (CH2, asym., sym.), 1521, 1345 (NO2); 1H-NMR, dH : 1.06(9H, s, t-Bu), 4.92 (2H, s, CH2), 7.42-7.46 (5H, m, Ph), 7.63-7.65 (7H, m, Ph+Harom2+6), 8.23 (2H, d, J=8.23, Harom3+5); MS, (EI), (391.54); m/z: 334 (M - t-Bu, 100), 288 (M - t-Bu - NO2, 10), 256 (M - t-Bu - Ph, 20), 199 (Ph2SiOH+, 100); C23H25NO3Si.

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