(i) LDA, HMPT, THF, (ii) CuCl2, DMF; Multistep reaction;

in tetrahydrofuran Irradiation (UV/VIS); (N2 or Ar); 250-W sun lamp, 4.5 h; solvent is removed, extd. with pentane, filtered, evapd., flash cromatography(silica/CH2Cl2);

NaMn(CO)5 in tetrahydrofuran 0.5 h; Yield given. Further byproducts given. Yields of byproduct given. Title compound not separated from byproducts;

NaMn(CO)5 in tetrahydrofuran 0.5 h; Yield given. Further byproducts given. Yields of byproduct given;

in tetrahydrofuran (N2 or Ar); in a round-bottom flask manganese solution is added with stirring to the crotonate, stirring for 30 min; solvent is removed under reduced pressure, extd. with pentane, chromy. on silica gel(CH2Cl2), elem. anal., further products;