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Lithium chloride (0.39 g, 9.12 mmol) and copper (I) chloride (0.61 g, 4.56 mmol) were combined in 45 ml THF at ambient temperature and stirred 15 minutes, then cooled to 0° C. at which time ethylmagnesium bromide (1 M solution in THF, 45 mL, 45 mmol) was added. (S)-citronellyl bromide (5.0 g, 22.8 mmol) was added dropwise and the solution was allowed to warm slowly to ambient temperature with stirring overnight. The reaction was quenched by cautious addition of sat. NH4Cl (aq), and stirred with Et2O and sat. NH4Cl (aq) for 30 minutes. The phases were separated and the organic phase dried (MgSO4) and concentrated. The crude (R)-2,6-dimethyl-dec-2-ene was used without purification. To a solution of (R)-2,6-dimethyl-dec-2-ene (3.8 g, 22.8 mmol) in 50 mL acetone at 0° C. was added Jones' reagent (2.7 M in H2SO4 (aq), 40 mL, 108 mmol) and the solution was allowed to warm slowly to ambient temperature with stirring overnight. The mixture was partitioned between Et2O and H2O, the phases were separated, and the organic phase washed with brine, dried (MgSO4), and concentrated. The residue was purified by flash chromatography (8:1 hexanes:EtOAc) to afford 2.14 g (59%) of the titled compound as a colorless oil: LRMS: m/z 156.9 (M+); 1H NMR (400 MHz; CDCl3): δ2.33 (m, 2H), 1.66 (m, 1H), 1.43 (m, 2H), 1.23 (m, 5H), 1.10 (m, 1H), 0.86 (m, 6H). Jones' reagent was prepared as a 2.7M solution by combining 26.79 CrO3, 23 mL H2SO4, and diluting to 100 mL with H2O. (4R,5S)-4-Methyl-3-((R)-4-methyl-octanoyl)-5-phenyl-oxazolidin-2-one. To (R)-4-methyl-octanoic acid (2.14 g, 13.5 mmol) in 25 mL CH2Cl2 at 0° C. was added 3 drops DMF, followed by oxalyl chloride (1.42 mL, 16.2 mmol) resulting in vigorous gas evolution. The solution was warmed directly to ambient temperature, stirred 30 minutes, and concentrated. Meanwhile, to a solution of the oxazolidinone (2.64 g, 14.9 mmol) in 40 mL THF at −78° C. was added n-butyllithium (1.6 M soln in hexanes, 9.3 mL, 14.9 mmol) dropwise. The mixture was stirred for 10 minutes at which time the acid chloride in 10 mL THF was added dropwise. The reaction was stirred 30 minutes at −78° C., then warmed directly to ambient temperature and quenched with sat. NH4Cl. The mixture was partitioned between Et2O and sat. NH4Cl (aq), the phases were separated, and the organic phase dried (MgSO4), and concentrated to furnish 3.2 g of the titled compound as a colorless oil. LRMS: m/z 318.2 (M+); 1H NMR (400 MHz; CDCl3): δ 7.34 (m, 5H), 5.64 (d, J=7.3 Hz, 1H), 4.73 (quint, J=6.8 Hz, 1H), 2.96 (m, 1H), 2.86 (m, 1H), 1.66 (m, 1H), 1.47 (m, 2H), 1.26 (m, 5H), 1.13 (m, 1H), 0.88 (m, 9H). The crude product was used without purification. (3S,5R)-5-Methyl-3-((4R,5S)-methyl-2-oxo-5-phenyl-oxazolidine-3-carbonyl)-nonanoic acid tert-butyl ester. To a solution of diisopropylamine (1.8 mL, 12.6 mmol) in 30 mL THF at −78° C. was added n-butyllithium (1.6 M soln in hexanes, 7.6 mL, 12.1 mmol), and the mixture stirred 10 minutes at which time (4R,5S)-4-Methyl-3-((R)-4-methyl-octanoyl)-5-phenyl-oxazolidin-2-one (3.2 g, 10.1 mmol) in 10 mL THF was added dropwise. The solution was stirred for 30 minutes, t-butyl bromoacetate (1.8 mL, 12.1 mmol) was added quickly dropwise at −50° C., and the mixture was allowed to warm slowly to 10° C. over 3 hours. The mixture was partitioned between Et2O and sat. NH4Cl (aq), the phases were separated, and the organic phase dried (MgSO4), and concentrated. The residue was purified by flash chromatography (16:1 to 8:1 hexanes:EtOAc) to provide 2.659 (61%) of the titled compound as a colorless crystalline solid, mp=84-86° C. [α]D23+17.1 (c=1.00, CHCl3); 1H NMR (400 MHz; CDCl3): δ 7.34 (m, 5H), 5.62 (d, J=7.3 Hz, 1H), 4.73 (quint, J=6.8 Hz, 1H), 4.29 (m, 1H), 2.67 (dd, J=9.8, 16.4 Hz, 1H), 2.40 (dd, J=5.1, 16.4 Hz, 1H), 1.69 (m, 1H), 1.38 (s, 9H), 1.28 (m, 7H), 1.08 (m, 1H), 0.88 (m, 9H); 13C NMR (400 MHz; CDCl3). 176.45, 171.22, 152.71, 133.64, 128.86, 125.86, 80.83, 78.87, 55.33, 40.02, 38.21, 37.59, 36.31, 30.86, 29.29, 28.22, 23.14, 20.41, 14.36, 14.26. Anal. Calcd for C25H37NO5: C, 69.58; H, 8.64; N, 3.25. Found: C, 69.37; H, 8.68; N, 3.05. (S)-2-((R)-2-Methyl-hexyl)-succinic acid 4-tert-butyl ester. To a solution of (3S,5R)-5-Methyl-3-((4R,5S)-4-methyl-2-oxo-5-phenyl-oxazolidine-3-carbonyl)-nonanoic acid tert-butyl ester (2.65 g, 6.14 mmol) in 20 mL THF at 0° C. was added a precooled (0C) solution of LiOH monohydrate (1.0 g, 23.8 mmol) and hydrogen peroxide (30 wt % aqueous soln, 5.0 mL) in 10 mL H2O. The mixture was stirred vigorously for 90 minutes, then warmed to ambient temperature and stirred 90 minutes. The reaction was quenched at 0° C. by addition of 100 mL 10% NaHSO3 (aq), then extracted with Et2O. The phases were separated, and the organic phase washed with brine, dried (MgSO4), and concentrated. The titled compound was used without purification. (3S,5R)-3-Benzyoxycarbonylamino-5-methylnonanoic acid, tert-butyl ester-This compound was prepared similarly as described above starting with (S)-2-((R)-2-methylhexyl) succinic acid, 4-tert-butyl ester instead of (S)-2-((R)-2-methylpentyl) succinic acid, 4-tert-butyl ester to provide the titled compound as an oil (71.6% yield). 1HNMR (400 MHz; CDCl3) δ 0.81(t, 3H, J=4:40 Hz), 0.85(d, 3H, J=6.55 Hz), 1.06-1.20(m, 7H), 1.36(s, 9H), 1.38-1.50(m, 2H), 2.36(m, 2H), 3.99(m, 1H), 5.02(m+s, 3H), and 7.28-7.28(m, 5H). (3S,5R)-3-Amino-5-methyl-nonanoic acid, tert-butyl ester—This compound was prepared as described above starting with (3S,5R)-benzyoxycarbonylamino-5-methyl-nonanoic acid, tert-butyl ester instead of (3S,5R)-3-benzyoxycarbonylamino-5-methyl-octanoic acid, tert-butyl ester. Yield=97%. 1HNMR (400 MHz; CDCl3) δ 0.82(overlapping d and t, 6H), 1.02-1.08(m, 1H), 1.09-1.36(m, 6H), 1.39(s, 9H), 1.47(br s, 1H), 1.80(s, 2H), 2.13(dd, 1H, J=8.54 and 15.61 Hz), and 2.27(dd, 1H, J=4.15 and 15.38 Hz). (3S,5R)-3-Amino-5-methyl-nonanoic acid hydrochloride-A mixture of (3S,5R)-3-amino-5-methyl-nonanoic acid, tert-butyl ester (1.50 g, 6.16 mmol) in 3N HCl (100 mL) was heated at reflux for 3 hours, filtered hot over Celite, and concentrated to 30 mL in vacuo. The resulting crystals were collected, washed with additional 3N HCl, and dried to provide the title compound, mp 142.5-143.3° C. Additional crops were obtained from the filtrate to provide 1.03 g (70.4%). 1HNMR (400 MHz; CD3OD) δ=0.91 (t, 3H, J=6.84 Hz), 0.92(d, 3H, J=6.35 Hz), 1.16-1.26(m, 1H), 1.27-1.35(m, 4H), 1.38-1.45(m, 1H), 1.61 (br s, 1H), 1.63-1.68(m, 1H), 2.58 (dd, 1H, J=7.32 and 17.34 Hz), 2.69(dd, 1H, J=5.13 and 17.59 Hz), and 3.59(m, 1H). Anal. Calc'd for C10H21NO2.HCl: C, 53.68; H, 9.91, N, 6.26, Cl: 15.85. Found: C, 53.89; H, 10.11, N, 6.13. MS: M+1: 188.1.

1. stirringstirred 90 minutes
2. customThe reaction was quenched at 0° C. by addition of 100 mL 10% NaHSO3 (aq)
3. extractionextracted with Et2O
4. customThe phases were separated
5. washthe organic phase washed with brine
6. dry with materialdried (MgSO4)
7. concentrationconcentrated
8. customThe titled compound was used without purification
9. custom(3S,5R)-3-Benzyoxycarbonylamino-5-methylnonanoic acid, tert-butyl ester-This compound was prepared similarly