carbamic acid 1,1-dimethylethyl ester; [Ru(η3-2-C3H4Me)(CO)(1,1'-(Ph2P)2-ferrocene)][SbF6]; trifluoroacetic acid in tetrahydrofuran T=20 - 75°C; Inert atmosphere;

hydrogenchloride; potassium hydroxide 1) ether, reflux, 2) methanol, water, 0.5 h, reflux; Yield given. Multistep reaction;