1: 1.) EtMgBr; 2.) 5percent CH3COOH / 1.) THF, 24 h, r.t.; 2.) 0 deg C, THF/H2O 2: 80 percent / NaH / dimethylsulfoxide / 3 h / 60 °C 3: 98 percent / acetone, p-TsOH / Heating View Scheme

ethylmagnesium bromide; acetic acid 1.) THF, 24 h, r.t.; 2.) 0 deg C, THF/H2O; Yield given. Multistep reaction;

(i) EtMgBr, THF, (ii) /BRN= 1420755/, (iii) aq. HCl; Multistep reaction;

ethylmagnesium bromide; acetic acid 1.) THF, 15 h, r.t.; 2.) 0 deg C, THF, H2O; Multistep reaction;