Reaction Steps
Esterification of (R)-(−)-lavandulol {(86% ee, [α]24D−9.6 (c 0.1, MeOH), prepared according to the method described by Cardillo et al. (Cardillo, G., et al., J. Org. Chem., 53: 2354-2356 (1988))} with (S)-(+)-2-methylbutanoic acid using the same procedures as compound 2a gave 75 mg (75% yield) of 1a as clear oil. Optical purity: 99% ee; [α]24D+5.0 (c 0.1, MeOH); 1H NMR (C6D6): δ 0.83 (3H, t, J=7.29 Hz), 1.08 (3H, d, J=7.0 Hz), 1.35 (1H, m), 1.50 (3H, s), 1.59 (3H, t, J=0.80 Hz), 1.61 (3H, d, J=1.13 Hz), 1.68 (1H, m), 2.06 (2H, m), 2.28 (1H, sextet, 6.85 Hz), 2.42 (1H, quintet, 7.00 Hz), 4.12 (2H, m), 4.79 (1H, m), 4.83 (1H, quintet, J=1.51 Hz), 5.11 (1H, t, quintet, J=7.19, 1.52 Hz); 13C NMR (C6D6): δ 175.88, 146.31, 132.70, 122.00, 112.50, 66.68, 45.41, 41.22, 29.13, 26.00, 25.80, 20.00, 17.80, 16.50, 11.52; EI-MS m/z (%): 238 [M]+ (1), 169 (2), 156 (3), 136 (15), 121 (39), 107 (11), 93 (100), 85 (23), 80 (25), 69 (75), 57 (59), 41 (40); HREIMS: obsd. 238.1934, calcd. for C15H16O2 (M+): 238.1933.
