(R)-(+)-1-Phenylethyl isocyanate → HCID 14074449, compound

Participants

Reaction Steps

A stirred solution of 2.40 g (8.91 mmol) of α-trifluoromethyl-6-phenoxy-2-pyridinemethanol, 1.38 g (9.36 mmol) of (R)-(+)-1-phenylethyl isocyanate, and 22 mg (0.18 mmol) of 4-dimethylaminopyridine in 9 ml of benzene under a nitrogen atmosphere was heated at 50° C. for 17 hours. The reaction mixture was then diluted with 150 ml of ether and washed with 25 ml of 1N aqueous HCl, 25 ml of saturated aqueous NaHCO3, and 25 ml of saturated aqueous NaCl. The organic layer was dried (MgSO4) and concentrated under reduced pressure. Repeated chromatography of the residue on silica gel with benzene afforded first 1.77 g (48%) of the [R-(R*,R*)] diastereomer: Rf =0.10 (SiO2, benzene); 1H NMR (CDCl3) δ 1.52 (d, 6.8 Hz, 3H), 4.83 (quintet, 7.1 Hz, 1H), 6.01 (q, 6.1 Hz, 1H), 6.83 (d, 8.2 Hz, 1H), 7.11-7.37 (br m, 12H), and 7.68 (t, 7.8 Hz, 1H); and then 1.77 g (48%) of the [S-(R*,S*)] diastereomer: Rf =0.09 (SiO2, benzene); 1H NMR (CDCl3) δ 1.47 (d, 6.8 Hz, 3H), 4.80 (quintet, 7.0 Hz, 1H), 5.98 (q, 6.9 Hz, 1H), 6.86 (d, 8.3 Hz, 1H), 7.13-7.42 (br m, 12H), and 7.72 (t, 7.8 Hz, 1H).

Provenance & Evidence