in pentane T=125 - 140°C; 24 h;

potassium phosphate; 1,3-(4-Ph-OMe)2-5-Ph-1,3,4-triazinium perchlorate in 1,4-dioxane T=80°C; 33 h;

1: diethoxyphosphoryl-acetic acid ethyl ester With sodium hydride in tetrahydrofuran Metallation; 2: cyclobutyl ketone in tetrahydrofuran T=30°C; Wadsworth-Horner-Emmons reaction; 2 h;

1: diethoxyphosphoryl-acetic acid ethyl ester With sodium hydride in DMF (N,N-dimethyl-formamide) T=0°C; 0.583333 h; 2: cyclobutyl ketone in DMF (N,N-dimethyl-formamide) T=0°C; 1.08333 h;

1: cyclobutyl ketone With sodium hydride in tetrahydrofuran T=0°C; 0.166667 h; 2: diethoxyphosphoryl-acetic acid ethyl ester in tetrahydrofuran T=20°C; 2 h; Product distribution / selectivity;

1: 36 percent / DIBAL-H / tetrahydrofuran 2: 86 percent / sodium carbonate; peroxyacetic acid / 1,2-dichloro-ethane / 7.25 h / Heating View Scheme

1: 36 percent / DIBAL-H / tetrahydrofuran 2: 86 percent / sodium carbonate; peroxyacetic acid / 1,2-dichloro-ethane / 7.25 h / Heating 3: triethylamine / CH2Cl2 4: 1.09 g / lithium bromide / acetone / Heating 5: 22 percent Spectr. / triphenyltin hydride / benzene-d6 / 4 h / 80 °C View Scheme