1: N-Boc-pyrrolidine With sec.-butyllithium in tetrahydrofuran; cyclohexane T=-78°C; 3.5 h; 2: boric acid trimethyl ester in tetrahydrofuran; cyclohexane T=-78 - 0°C; 3: With hydrogenchloride in water pH=3;

catalyst: PtO2 in ethyl acetate inert atmosphere; hydrogenation (50 psi, 8 h) of stirred suspn. of B-compd. and Adam's catalyst, reaction mixt. filtration (Celite), pptn. on filtrat concn. (vac.); elem. anal.;

1: With N,N,N',N,-tetramethylethylenediamine; sec.-butyllithium in diethyl ether T=-78°C; 4 h; 2: With tri-isopropoxy-borane in diethyl ether T=-78 - 20°C; Further stages.;

in chloroform 12 h;