Ozone → 3-(Tertbutyldiphenylsilyloxymethylene)-pentane-1,5-diol

Reaction equation

O=[O+][O-].[Si:4]([O:21][CH:22]=[C:23]([CH2:27][CH2:28][OH:29])[CH2:24][CH2:25][OH:26])(C(C)(C)C)([C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1)[C:5]1[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=1.[BH4-].[Na+]>CO>[C:23]([C:22](=[C:23]([CH2:27][CH2:28][OH:29])[CH2:24][CH2:25][OH:26])[O:21][SiH:4]([C:5]1[CH:6]=[CH:7][CH:8]=[CH:9][CH:10]=1)[C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1)([CH3:27])([CH3:24])[CH3:22]

Participants

Procedure

Ozone was bubbled through a -78° C. dry methanol (500 mL) solution of 3-(tert-butyldiphenylsilyloxymethylene)-1,5-pentanediol (17 g, 47 mmol) until a blue tint persisted (30 minutes). The reaction was purged with nitrogen (20 min.) and NaBH4 (17.6 g, 47 mmol) was added. The cold bath was removed and the reaction brought to room temperature. The reaction was concentrated in vacuo and the residue partitioned between ether and brine. The ether layer was concentrated and the residue eluted over a silica plug with 0-50% ethyl acetate/hexanes. The minor component was pooled and concentrated to yield the diol , 3-(tertbutyldiphenylsilyloxymethylene)-pentane-1,5-diol, 3.8 g (22%) of the desired diol as a colorless oil. Overall the yield for the three steps is 17%. MS.