1: 61 percent / NaH / tetrahydrofuran / 1.) 0 deg C, 6 h, 2.) r.t., overnight 2: 97 percent / 90percent aq. TFA / 3 h 3: 89 percent / 6 h / Heating View Scheme

1: 61 percent / NaH / tetrahydrofuran / 1.) 0 deg C, 6 h, 2.) r.t., overnight 2: 97 percent / 90percent aq. TFA / 3 h 3: 89 percent / 6 h / Heating 4: 95 percent / ethanol / 4 h / Ambient temperature 5: 97 percent / K2CO3 / acetone / 10 h / Heating View Scheme

1: 61 percent / NaH / tetrahydrofuran / 1.) 0 deg C, 6 h, 2.) r.t., overnight 2: 97 percent / 90percent aq. TFA / 3 h 3: 89 percent / 6 h / Heating 4: 95 percent / ethanol / 4 h / Ambient temperature View Scheme