bromine in dichloromethane T=20°C; 6 h;

CM-phos; H2O4P(1-)*3K(1+); palladium diacetate; triethylamine in tert-butyl alcohol T=20 - 110°C; Suzuki-Miyaura coupling; Inert atmosphere;

KHF2 in tetrahydrofuran T=20°C;

in tetrahydrofuran; water boronic acid dissolved in THF; treated with aq. KHF2 (excess); stirred at room temp. overnight; THF removed under reduced pressure on rotary evaporator; H2O removed by lyophilization; extd. with acetone; combined extracts concd. under reduced pressure; residue washed with ether; elem. anal.;

1: With boric acid trimethyl ester in tetrahydrofuran T=-30 - 20°C; Inert atmosphere; 2: With KHF2 in tetrahydrofuran; water T=-10 - 20°C; 2 h;

hydrogenchloride in methanol; diethyl ether; water Mg compd. added to soln. of B compd. at -65--70°C dropwise within1.5 h, warmed to 20°C within 3 h, hydrolysed with aq. HCl, org. phase sepd., aq. phase extd. with ether, dried with MgSO4, dissolved in MeOH, reacted with aq. B compd.; after 5 min filtered, dried, extd. with hot acetone, solvent removed in vac., dried over P4O10, elem. anal.;

(2S)-3-Methyl-2-(methylcarbonyl)aminobutyric acid; palladium diacetate; lithium carbonate; N,N-dimethyl-formamide; silver carbonate in tert-butyl alcohol T=110°C; 2 h; Schlenk techniqueInert atmosphere;