1: n-butyllithium; diethylamine in hexane T=-7 - 26°C; 0.25 - 3.33333 h; 2: titanium bis(diethylamido)dichloride; ClTi(NEt2)3 in tetrahydrofuran; hexane T=20 - 38°C; 0.833333 - 48 h;