high osmium...
according to https://www.thevespiary.org/rhodium/Rhodium/chemistry/phenylacetone.html#phenylacetic (https://www.thevespiary.org/rhodium/Rhodium/chemistry/phenylacetone.html#phenylacetic)
the reaction gives the best results when that much catalyst is used (and sodium acetate is very cheap too).
But next time swim will use less catalyst, because the reaction is hard to handle with that much salt in it :P - then a heating mantle can also be used to heat the reaction mixture. (having an oil bath 20H @ 160°C gives the workspace this disgusting McDonalds-smell ::) )
...but finally it worked, with a very nice yield :)