Reaction SMILES: O=O.C(S)CCC.C1C=CC(P(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.[C:27]([O:35][C@@H:36]1[C@:43]([CH3:45])([OH:44])[C@H:42]2[CH2:46][C@@H:38]([C@:39]([CH2:48][S:49][CH2:50][CH2:51][CH2:52][CH3:53])([CH3:47])[O:40][O:41]2)[CH2:37]1)(=[O:34])[C:28]1[CH:33]=[CH:32][CH:31]=[CH:30][CH:29]=1>CCCCCC.C1C=CC=CC=1.CCCCCC.CCCCCC.CCOC(C)=O>[C:27]([O:35][C@@H:36]1[C@:43]([CH3:45])([OH:44])[C@@H:42]2[CH2:46][C@@H:38]([C@@:39]([CH2:48][S:49][CH2:50][CH2:51][CH2:52][CH3:53])([CH3:47])[O:40][O:41]2)[CH2:37]1)(=[O:34])[C:28]1[CH:33]=[CH:32][CH:31]=[CH:30][CH:29]=1
Reactant: CCCCSC[C@@]1(C)OO[C@@H]2C[C@@H]1C[C@H](OC(=O)c1ccccc1)[C@]2(C)O
Agent: O=O
Agent: c1ccc(P(c2ccccc2)c2ccccc2)cc1
Solvent: CCCCS
Solvent: CCCCCC
Solvent: c1ccccc1
Product: CCCCSC[C@]1(C)OO[C@H]2C[C@@H]1C[C@H](OC(=O)c1ccccc1)[C@]2(C)O
Temperature: 5 °C
Reaction time: 14 h
Yield: 6.5 %

Procedure:
Oxygen was bubbled through a solution of the β-benzoate 3a (993 mg, 3.87 mmol) and DBPO (23 mg, 0.1 mmol) in hexane-benzene (50 mL, 4:1) with simultaneous addition (syringe pump) during 10 h a solution of n-BuSH (180 mg, 2.0 mmol) in hexane (20 mL). After completion of the addition the mixture was kept under oxygen for an additional 14 h, cooled to 5° C., and Ph3P (526 mg, 2.0 mmol) was added. The reaction mixture was stirred for 2 h at 5° C., for additional 1 h at rt and then evaporated. Flash chromatography (hexane-EtOAc, 9:1→7:3) afforded a mixture of diastereomeric (1S,4S,5S,7S,8S)-7-benzoyloxy-4-n-butylthiomethyl-4,8-dimethyl-2,3-dioxabicyclo[3.3.1]nonan-8-ol 5a and (1S,4R,5S,7S,8S)-7-benzoyloxy-4-n-butylthiomethyl-4,8-dimethyl-2,3-dioxabicyclo[3.3.1]nonan-8-ol 5b (59 mg of ~85% purity, ca. 6.5% yield; 5a/5b ca. 55:45) as a pale yellow viscous liquid, Rf 0.26 (hexane-EtOAc, 4:1). 1H NMR (400 MHz, CDCl3, δ): 0.91 (t, 3J=7.3 Hz, Me16CH2, 5b), 0.92 (t, 3J=7.3 Hz, Me16CH2, 5a), total 3 H; 1.36 (br. s, Me11, 5a), 1.58 (br. s, Me11, 5b), total 3 H, 1.42 (m, 2 H, MeC15H2), 1.43 (s, Me10, 5b), 1.44 (s, Me10, 5a), total 3 H; 1.60 (m, 2 H, C14H2CH2S), 1.78 (ddd, 2J=13.3 Hz, 3J6a7a =11.6 Hz, 3J6a5e =3.4 Hz, Ha6, 5b), 1.82 (ddd, 2J=13.2 Hz, 3J6a7a =11.8 Hz, 3J6a5e =3.5 Hz, Ha6, 5a), 1 H total; 1.96-2.52 (m, total 4 H, He5 +He6 +He,a9, 5a+5b), 2.59 (br. t, 3J=7.3 Hz, CH2S, 5a), 2.61 (br. t, 3J=7.3 Hz, C13H2S, 5b), total 2 H; 2.60 (br. d, 2J=12.2 Hz, H12,5b), 2.80 (br. d, 2J=12.2 Hz, H'12,5b), 2.96 (br. d, 2J=13.2 Hz, H12, 5a), 3.20 (br. d, 2J=13.2 Hz, H'12, 5a), total 2 H; 3.97 (br. s, 1 H, He1, 5a +5b), 5.76 (m, 1 H, Ha7, 5a+5b), 7.46 (m, 2 H, Hm-benz.,5a+5b), 7.59 (m, 1 H, Hp-benz., 5a+5b), 8.03 (m, 2 H, H0-benz., 5a+5b); 13C NMR (100 MHz, CDCl3, δ): Isomer 5a: 13.67 (Me16), 21.89 (C15H2), 22.09 (Me11), 23.79 (C9H2), 24.44 (Me10), 29.33 (C6H2), 31.58 (C5H), 31.82 (C14H2), 33.47 (C13H2), 38.16 (C12H2), 72.81 (C8), 74.79 (C7H), 82.73 (C1H), 83.81 (C4), 128.50 (2Cm-benz. H), 129.46 (2Co-benz.H), 130.05 (C1-benz.), 133.20 (Cp-benz.H), 165.58 (C=O); Isomer 5b: 13.62 (Me16), 20.66 (Me11), 21.85 (C15H2), 23.89 (C9H2), 24.44 (Me10), 28.99 (C6H2), 31.54 (C14H2), 32.59 (C5H), 33.67 (C13H2), 38.88 (C12H2), 72.80 (C8), 74.96 (C7H), 83.15 (C1H), 83.92 (C4), 128.50 (2Cm-benz.H), 129.46 (2Co-benz.H), 130.09 (C1-benz.), 133.17 (Cp-benz.H), 165.58 (C=O).