1: 27 percent / (NH4)2S2O8 / AgNO3 / acetonitrile; H2O / 0.17 h / Heating 2: 1) Disiamylboran, 2) PCC / 1) Et2O, 0 deg C, 3h, 2) CH2Cl2, 2h, reflux View Scheme

1: 27 percent / (NH4)2S2O8 / AgNO3 / acetonitrile; H2O / 0.17 h / Heating 2: 1) Disiamylboran, 2) PCC / 1) Et2O, 0 deg C, 3h, 2) CH2Cl2, 2h, reflux View Scheme

Disiamylboran; pyridinium chlorochromate 1) Et2O, 0 deg C, 3h, 2) CH2Cl2, 2h, reflux; Yield given. Multistep reaction;