tert-Butanol → Tert-butyl 7-cyano-2-naphthylcarbamate

Beteiligte Stoffe

Reaktionsschritte

A solution of acid 192 (6.60 g, 23 mmol), diphenyl phosphorazidate (7.71 g, 28 mmol) and Et3N (5.19 g, 51 mmol) in t-BuOH (50 mL) was heated under reflux for 6 h. The mixture was partitioned between EtOAc and brine. The EtOAc layer was dried and filtered through silica gel. Chromatography eluting with CH2Cl2/petroleum ether/MeOH (25:24:1) followed by recrystallization (CH2Cl2/petroleum ether) gave tert-butyl 7-cyano-2-naphthylcarbamate (193) (5.30 g, 85%) as colorless needles. A sample was recrystallised (EtOAc/n-hexane): mp 126-128° C.; 1H NMR (CDCl3) δ 8.13 (s, 1H), 8.07 (s, 1H), 7.82 (d, J=8.1 Hz, 1H), 7.80 (d, J=8.1 Hz, 1H), 7.51-7.48 (m, 2H), 6.71 (br s, 1H), 1.56 (s, 9H); 13C NMR δ 152.5, 137.5, 133.4, 133.1, 131.0, 128.9, 128.8, 124.9, 122.0, 119.3, 114.4, 110.0, 81.3, 28.3. Anal. (C16H16N2O2) C, H, N.

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