in hexane react. 2,4,6-tri-t-butylanilidolithium with BCl3 in n-C6H14 at -78°C, then -4°C for 12 h; product filtered and crystd. at -30°C from concd. filtrate followed by sublimation; elem. anal.;

in diethyl ether react. 2,4,6-tri-t-butylanilidolithium with BF3*(OEt2) in OEt2 at 25°C for 12 h; product filtered and crystd. at -30°C from concd. filtrate followed by sublimation; elem. anal.;

Multi-step reaction with 3 steps 1: 90 percent / tetrahydrofuran; hexane / 2 h2: 1) MeLi, 2) Me3SiCl / 1) ether, 2) ether, THF, 1 h3: 98 percent / 80 °C / 0.01 Torr