tributylphosphine; sodium hydrogencarbonate; ozone 1.) CH2Cl2, MeOH, -78 deg C, 2.) r.t., 2 h; Yield given. Multistep reaction;

1: 1.) Hg(OAc)2; 2.) NaBH4, aq. NaOH / 1.) H2O, THF, room temp., 10 min; 2.) 10 min, ice/water bath 2: 65 percent / n-butyl nitrite, aq. HCl / aq. ethanol / 6 h View Scheme