C[O:2][C:3](=[O:17])[CH:4]([CH2:13][CH:14]([CH3:16])[CH3:15])[CH2:5][C:6]([O:8][C:9]([CH3:12])([CH3:11])[CH3:10])=[O:7].[Cl-].[Li+]>CS(C)=O.O>[C:9]([O:8][C:6](=[O:7])[CH2:5][CH:4]([CH2:13][CH:14]([CH3:15])[CH3:16])[C:3]([OH:17])=[O:2])([CH3:12])([CH3:11])[CH3:10]Cyanoester 2 (0.76 g, 3.91 mmol), water (0.14 mL, 7.82 mmol) and lithium chloride (0.66 g, 15.6 mmol) were heated to 150° C. in DMSO (40 mmL) for 22 hours. The mixture was allowed to cool, diluted with water (150 mL), and extracted with ether (3×50 mL). The combined ether fractions were washed with brine, dried (MgSO4), and the solvent was evaporated under reduced pressure. The residue was chromatographed (SiO2, heptane-ethyl acetate, 95:5) to give the cyanide 3 (0.21 g, 44%) as a 60:40 mixture of diastereoisomers; Rf(heptane-ethyl acetate, 9:1) 0.44; νmax(film)/cm−1 2238 (CN); Major diastereoisomer: δH (400 MHz; CDCl3) 2.97 (1H, m), 2.87 (2H, m), 2.32–2.18 (2H, m), 2.10–1.96 (3H, m), 1.92–1.78 (2H, m), 1.48–1.38 (1H, m); Minor diastereoisomer: δH (400 MHz; CDCl3) 3.13 (1H, m), 2.87 (2H, m), 2.32–2.18 (2H, m), 2.10–1.96 (3H, m), 1.92–1.78 (2H, m), 1.48–1.38 (1H, m).
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