Compound 2e

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Synthetic procedure: See article for the definitive version of this procedure and for full experimental details.

Prepared according to general procedure 2 outlined for compound 2a from (2E,9E)-6-acetyl-6-(methoxycarbonyl)undeca-2,9-diene-1,11-diyl diacetate 1e (49.4 mg, 0.134 mmol). After a reaction time of 21 h at −50 °C, the crude product was separated from the ligand (see Note B above) and purified by column chromatography (hexane/EtOAc 90:10 to 80:20) to afford diastereopure 2e as a colorless oil (33.3 mg, 80%, er: 92:8). ¹H NMR (400 MHz, CDCl₃) δ5.81 (ddd, 1 H, J = 17.0, 10.2, 7.2 Hz, CH=CH₂), 5.72 (dt, 1 H, J = 15.2, 6.3 Hz, AcOCH₂CH=CH), 5.56 (dt, 1 H, J = 15.2, 6.3 Hz, AcOCH₂CH=CH), 5.07 (d, 1 H, J = 10.2 Hz, CH=CH_cisH_trans), 5.04 (d, 1 H, J = 17.0 Hz, CH=CH_cisH_trans), 4.49 (d, 2 H, J = 6.5 Hz, AcOCH₂), 3.73 (s, 3 H, CO₂CH₃), 3.48–3.43 (bs, 1 H, OH), 2.57–2.48 (m, 1 H, CHCH=CH₂), 2.44–2.35 (m, 1 H, CHCH₂CH_aH_bCCO₂CH₃), 2.06 (s, 3 H, CH₃CO₂), 2.06–1.82 (m, 4 H, CH₂CH₂CH=CH + CH_aH_bCH₂CH=CH + CHCH_aH_bCH₂CCO₂CH₃), 1.58–1.40 (m, 3 H, CH_aH_bCH₂CH=CH + CHCH₂CH_aH_bCCO₂CH₃ + CHCH_aH_bCH₂CCO₂CH₃), 1.08 (s, 3 H, CH₃COH); ¹³C NMR (100 MHz, CDCl₃) δ177.5 (CO₂CH₃), 170.9 (CH₃CO₂), 138.0 (CH=CH₂), 135.4 (AcOCH₂CH=CH), 124.3 (AcOCH₂CH=CH), 116.2 (CH=CH₂), 82.7 (COH), 65.1 (AcOCH₂), 58.9 (CCO₂CH₃), 53.2 (CHCH=CH₂), 52.1 (CO₂CH₃), 33.3 (CH₂CH₂CH=CH), 30.4 (CHCH₂CH₂CCO₂CH₃), 28.4 (CH₂CH₂CH=CH), 24.8 (CHCH₂CH₂CCO₂CH₃), 21.1 (CH₃CO₂), 19.0 (CH₃COH); ); IR ν_max (neat/cm^-1): 3491, 2951, 2346, 1735, 1638, 1436, 1364, 1228, 1142, 1095, 1024, 967, 912, 819, 668, 643; HRMS (APCI) calcd for C₁₇H₂₇O₅, [M+H]⁺: 311.1853, found 311.1850. [α]²²_D = +23.7 (c = 0.15, CH₂Cl₂).

Enantiomeric purity of the product was determined by GC analysis (ChiraSil^® DEX CB 25 m x 0.25 mm column, isothermal at 100 °C for 720 min/120 °C to 125 °C (1 °C/min)/isothermal at 125 °C (120 min)/125 °C to 140 °C (1 °C/min)/isothermal at 140 °C, flow rate = 1.0 mL/min, retention time: 918.3 min (minor), 921.8 min (major); er: 92:8.