Unseld et al reported a novel mono and bis (alkynyl) Mn(II) and Mn(III) complexes with terminal or trimetyltin substituted acetylenes. In particular I was interested on stanylation terminal hydrogen at ethynyl aryls. I used this approach to stanylate following compounds: ethynylbenzene, 1-(tert-butyl)-4-ethynylbenzene, 1-((2-ethylhexyl)oxy)-4-ethynylbenzene, and 2-(2-ethylhexyl)-5-ethynylthiophene. I used the exact procedure that Unseld et al reported. I was able to synthesized four different aryl substituents in a high yield ~ 95 %.
However, I modified the purification part. According Unseld et al, once the stanylation step proceed, the resulting suspension was removed by rotary evaporation until an oily suspension formed. Then, the product was dissolved in pentane and filtered through the glass frit. The product was isolated by rotary evaporation the solvent. In my procedure, for safety, once the stanyaltion step was done, the reaction was quenched by pouring the mixture in to ice-water. The product was extracted by liquid-liquid extraction with pentane, dried over anhyd. Magnesium sulfate. The product was isolated by rotary evaporation the solvent.
The experimental section was well written and easy to follow. I followed this reaction number of time, each time I was able to reproduce the reaction with high yield, even after using the modified purification method.