4-CHLORO-4,4-DIFLUORO-1-(4-METHOXY-PHENYL)-BUTANE-1,3-DIONE synthesis

Yield:-

Reaction Conditions:

Stage #1:1-(4-methoxyphenyl)ethanone with sodium hydride in diethyl ether at 0; for 0.166667 h;
Stage #2:metyhyl chlorodifluoroacetate in diethyl ether at 0 - 20; for 14 h;

Steps:

3.2. General procedure for the synthesis of compounds 6
General procedure: To a solution of NaH (1.1 equiv) in ether (2.0 mL/mmol SM) was added acetophenone (1.0 equiv) at 0 °C. The solution was stirred at 0 °C for 10 min before methyl 2-chloro-2,2-difluoroacetate (1.0 equiv) was added. The temperature was allowed to rise to 20 °C over 14 h. To the solution was added HCl (10%) and the mixture was extracted with Et₂O. The organic layers were dried over Na₂SO₄, filtered and the filtrate was concentrated in vacuo. The residue was purified by chromatography (heptane/EtOAc) to give the chlorodifluoroketones.

References:

Iaroshenko, Viktor O.;Specowius, Verena;Vlach, Katharina;Vilches-Herrera, Marcelo;Ostrovskyi, Dmytro;Mkrtchyan, Satenik;Villinger, Alexander;Langer, Peter [Tetrahedron,2011,vol. 67,# 31,p. 5663 - 5677] Location in patent:experimental part