1: 66 percent / silver triflate, collidine / nitromethane / 1) -25 deg C, 30 min, 2) RT, 4.5 h 2: 86 percent / ammonium cerium(IV) nitrate / acetonitrile; H2O / Ambient temperature; 1) 0 deg C, 10 min, 2) RT, 45 min View Scheme

With  2,3,5-trimethyl-pyridine; silver trifluoromethanesulfonate in  nitromethane  1) -25 deg C, 30 min, 2) RT, 4.5 h;   

Multi-step reaction with 2 steps 1: 90 percent / 1) NaH / tetrahydrofuran / 21 h / Ambient temperature2: 1) sodium cyanoborohydride, mol. sieves 3A, 2) TFA / 1) DMF, 15 min, RT, 2) DMF, 43 h  

Multi-step reaction with 5 steps 1: 54 percent / silver zeolite / CH2Cl2 / 40 h / Ambient temperature2: 99 percent / methanol / 0.5 h3: 64 percent / p-TsOH*H2O / acetonitrile / 0.83 h / Ambient temperature4: 90 percent / 1) NaH / tetrahydrofuran / 21 h / Ambient temperature5: 1) sodium cyanoborohydride, mol. sieves 3A, 2) TFA / 1) DMF, 15 min, RT, 2) DMF, 43 h