2-(4-Methoxymethoxy-thianthren-1-yl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane (6.23 g, 17.14 mmol), 2-chloro-6-morpholin-4-yl-pyran-4-one (3) (6.99 g, 17.40 mmol) and powdered potassium carbonate (7.20 g, 52.20 mmol) were suspended in anhydrous dioxane (60 ml) under a nitrogen atmosphere. The mixture was degassed for 15 minutes before the addition of tetrakis(triphenylphosphino)palladium (1.2 g, 5% eq) and then degassed for a further 15 minutes after addition. The reaction was then heated at 90° C. for 24 hours. Water (60 ml) was added and the mixture extracted with EtOAc (3×30 ml). The organic extracts were then dried using MgSO4, filtered and concentrated in vacuo to yield a dark yellow oil. The crude residue was then purified by flash chromatography (SiO2) (9:1—EtOAc/MeOH) to give the title compound (7.93 g, 79%) as a green powder. m/z (LC-MS, ESP): RT=4.39 min, (M++1)=456
