2.) acid 1.) THF, -78 deg C, 0.5 h.; Yield given. Multistep reaction. Yields of byproduct given;

2.) acid 1.) THF, -78 deg C, 0.5 h.; Yield given. Multistep reaction. Yields of byproduct given;

2.) acid 1.) THF, -78 deg C, 0.5 h.; Yield given. Multistep reaction. Yields of byproduct given;

sulfuric acid in tetrahydrofuran byproducts: YbCl2; Sn-complex was added under N2 to soln. of Yb-complex in THF at 0°C for 2.5 h, solvent was removed under vac., residue was hydrolysed with H2SO4; organic layer was washed with aq. NaHCO3, dried, evapd., recrystd. from aq. EtOH;

in tetrahydrofuran byproducts: YbCl2; HgCl2 was added under N2 to soln. of Yb-complex in THF at -78°C for 0.5 h, solvent was removed under vac., H2O was added, residue was hydrolysed with ether/H2O or CHCl3/H2O; organic layer was washed with aq. NaHCO3, dried, evapd., recrystd. from aq. MeOH and petrol;