1: 68 percent / CrO3, 6 N H2SO4 / acetone / 3.5 h, ice-cold then RT 2: diethyl ether View Scheme

in hexane; sulfuric acid; water; acetone

1: 68 percent / CrO3, 6 N H2SO4 / acetone / 3.5 h, ice-cold then RT 2: 1.) sodium borohydride, 2.) 5percent HCl / 1.) ethanol, 5 min, 2.) RT View Scheme

1: 68 percent / CrO3, 6 N H2SO4 / acetone / 3.5 h, ice-cold then RT 2: 1.) sodium borohydride, 2.) 5percent HCl / 1.) ethanol, 5 min, 2.) RT 3: 1.) sodium borohydride, ethylenediamine 2.) 5percent HCl / P-2 nickel / 1.) ethanol, 23 deg C, 1 h View Scheme

1: 68 percent / CrO3, 6 N H2SO4 / acetone / 3.5 h, ice-cold then RT 2: 1.) sodium borohydride, 2.) 5percent HCl / 1.) ethanol, 5 min, 2.) RT 3: 1.) sodium borohydride, ethylenediamine 2.) 5percent HCl / P-2 nickel / 1.) ethanol, 23 deg C, 1 h 4: 30 percent / 2,2'-dipyridyl disulfide, triphenylphosphine, silver perchlorate / 1.) THF, 1.5 h, 23 deg C, 2.) xylene, 10 h, reflux View Scheme