hydrogenchloride; air; carbon dioxide in diethyl ether Passing of gaseous CO2 through Et2O soln. of Ti-compd. (Ar) for 1 h, hydrolysis with aq. HCl and then bubbling of air into react. mixt. for 15 min.; Collecting of pptd. crystals of Cp2TiCl2 by filtn., addn. of aq. NaOH, sepn. of org. layer and discarding. Extn. of aq. layer with ether, discarding, addn. of concd. HCl, extn. with ether, drying, concn. in vac. Purifn. by trap-to-trap distn., (1)H NMR.;

carbon dioxide byproducts: 2-methyl-3-butenoic acid, H2O;

hydrogenchloride; air; carbon dioxide in diethyl ether Passing of gaseous CO2 through Et2O soln. of Ti-compd. (Ar) for 1 h, hydrolysis with aq. HCl and then bubbling of air into react. mixt. for 15 min.; Collecting of pptd. crystals of Cp2TiCl2 by filtn., addn. of aq. NaOH, sepn. of org. layer and discarding. Extn. of aq. layer with ether, discarding, addn. of concd. HCl, extn. with ether, drying, concn. in vac. Purifn. by trap-to-trap distn., (1)H NMR.;