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PRACTICAL SYNTHETIC PROCEDURES
Cyclohexyl Acetoacetate (3f)
Menthyl Acetoacetate (3b)5b
Following the general procedure on a 15 mmol scale gave 3b as a
viscous oil; yield: 3.53 g (98%).
Following the general procedure on a 5 mmol scale gave 3f as a vis-
cous liquid; yield: 0.91 g (99%).
[a]D25 –72.4 (c 3.08, EtOH) [Lit.5b –72.0 (c 10.4, benzene)].
IR (neat, NaCl): 2939.2, 2860.8, 1740.1, 1715.2, 1649.7, 1238.5,
1151.4 cm–1.
1H NMR (250 MHz, CDCl3): d = 1.25–1.60 (m, 6 H), 1.82–1.90 (m,
2 H), 1.92–1.97 (m, 2 H), 2.28 (s, 3 H), 3.44 (s, 2 H), 4.79–4.86 (m,
1 H).
13C NMR (63 MHz, CDCl3): d = 23.9, 25.6, 30.3, 31.7, 50.8, 74.0,
166.9, 201.1.
IR (neat, NaCl): 2956.5, 2871.0, 1740.9, 1716.1, 1646.3, 1243.0,
1148.9 cm–1.
1H NMR (250 MHz, CDCl3): d = 0.79 (d, J = 6.9 Hz, 3 H), 0.92 (d,
J = 7.0 Hz, 3 H), 0.93 (d, J = 6.5 Hz, 3 H), 0.99–1.14 (m, 2 H),
1.34–2.08 (m, 7 H), 2.28 (s, 3 H), 3.46 (s, 2 H), 4.76 (td, J = 10.9,
4.4 Hz, 1 H).
13C NMR (63 MHz, CDCl3): d = 16.5, 21.1, 22.4, 23.6, 26.5, 30.4,
31.8, 34.5, 41.1, 47.2, 50.9, 75.8, 167.1, 201.1.
Anal. Calcd for C10H16O3: C, 65.19; H, 8.75. Found: C, 65.00; H,
8.66.
Anal. Calcd for C14H24O3: C, 69.96; H, 10.07. Found: C, 69.74; H,
9.91.
tert-Butyl Acetoacetate (3g)
Following the general procedure on a 5 mmol scale gave 3g as a vis-
cous liquid; yield: 0.78 g (99%).
8-Phenylmenthyl Acetoacetate (3c)4a
Following the general procedure on a 4 mmol scale gave 3c as a vis-
cous oil; yield: 1.25 g (99%).
IR (neat, NaCl): 2981.5, 2932.1, 1741.0, 1716.1, 1369.3, 1256.5,
1146.0 cm–1.
[a]D25 +9.7 (c 0.64, CH2Cl2) [Lit.4a +10.6 (c 1.3, CHCl3)].
1H NMR (250 MHz, CDCl3): d = 1.49 (s, 9 H), 2.27 (s, 3 H), 3.37
(s, 2 H).
IR (neat, NaCl): 2955.8, 2823.6, 1739.2, 1715.4, 1644.3, 1243.3,
1152.9 cm–1.
1H NMR (250 MHz, CDCl3): d = 0.91 (d, J = 6.5 Hz, 3 H), 1.23 (s,
3 H), 1.33 (s, 3 H), 0.92–2.10 (m, 8 H), 2.13 (s, 3 H), 2.67 (d,
J = 15.7 Hz, 1 H), 2.80 (d, J = 15.7 Hz, 1 H), 4.86 (td, J = 10.8, 4.4
Hz, 1 H), 7.22–7.34 (m, 5 H).
13C NMR (63 MHz, CDCl3): d = 28.2, 30.3, 51.7, 82.1, 166.7,
201.4.
Anal. Calcd for C8H14O3: C, 60.74; H, 8.92. Found: C, 60.42; H,
8.79.
( )-1-(Ethoxycarbonyl)prop-2-yl Acetoacetate (3h)
Following the general procedure on a 5 mmol scale gave 3h as a vis-
cous liquid; yield: 1.06 g (98%).
IR (neat, NaCl): 2938.5, 1739.0, 1638.4, 1360.1, 1192 cm–1.
1H NMR (250 MHz, CDCl3): d = 1.27 (t, J = 7.2 Hz, 3 H), 1.34 (d,
J = 6.6 Hz, 3 H), 2.28 (s, 3 H), 2.39 (dd, J = 15.7, 7.6 Hz, 1 H), 2.53
(dd, J = 15.7, 7.6 Hz, 1 H), 3.43 (s, 2 H), 4.15 (q, J = 7.2 Hz, 2 H),
5.27–5.45 (m, 1 H).
13C NMR (63 MHz, CDCl3): d = 22.2, 23.8, 26.7, 29.6, 30.5, 31.7,
34.9, 39.9, 41.8, 50.2, 50.6, 75.5, 125.5, 125.8, 128.4, 152.3, 166.9,
201.3.
Anal. Calcd for C20H28O3: C, 75.91; H, 8.92. Found: C, 75.58; H,
8.71.
Cholesteryl Acetoacetate (3d)7,12
Following the general procedure on a 15 mmol scale gave 3d as a
white solid; yield: 6.85 g (97%); mp 92–93 °C.
[a]D25 –35.7 (c 0.7, CHCl3) [Lit.12 –35 (no concentration given,
CHCl3)].
13C NMR (63 MHz, CDCl3): d = 14.4, 19.9, 30.3, 40.8, 50.4, 60.9,
68.7, 166.6, 170.3, 200.8.
Anal. Calcd for C10H16O5: C, 55.55; H, 7.46. Found: C, 55.28; H,
7.32.
IR (neat, NaCl): 2949.8, 2867.9, 1742.5, 1724.1, 1643.7, 1235.4,
1162.3 cm–1.
N-Benzylacetoacetamide (3i)
Following the general procedure on a 5 mmol scale gave 3i as a
pale-yellow solid; yield: 0.75 g (79%); mp 92–93 °C.
1H NMR (250 MHz, CDCl3): d = 0.70 (s, 3 H), 0.88 (d, J = 6.6 Hz,
3 H), 0.89 (d, J = 6.6 Hz, 3 H), 0.94 (d, J = 6.5 Hz, 3 H), 1.04 (s, 3
H), 1.08–2.06 (m, 26 H), 2.29 (s, 3 H), 2.37 (d, J = 7.8 Hz, 2 H),
3.45 (s, 2 H), 4.63–4.76 (m, 1 H), 5.41 (d, J = 4.9 Hz, 1 H).
13C NMR (63 MHz, CDCl3): d = 12.3, 19.1, 19.7, 21.4, 23.0, 23.3,
24.3, 24.7, 28.0, 28.4, 28.6, 30.5, 32.2, 32.3, 36.2, 36.6, 36.9, 37.3,
38.3, 39.9, 40.1, 42.7, 50.4, 50.8, 56.5, 57.0, 75.5, 123.3, 139.7,
166.9, 201.1.
IR (neat, NaCl): 3249.9, 3085.2, 2935.6, 1714.3, 1640.7, 1443.3,
1239.8, 1189.6 cm–1.
1H NMR (250 MHz, CDCl3): d = 2.29 (s, 3 H), 3.47 (s, 2 H), 4.48
(d, J = 5.8 Hz, 2 H), 7.29–7.36 (m, 5 H).
13C NMR (63 MHz, CDCl3): d = 31.2, 43.8, 50.2, 127.8, 128.1,
129.1, 138.4, 166.3, 204.8.
Anal. Calcd for C31H50O3: C, 79.10; H, 10.71. Found: C, 78.88; H,
10.59.
Anal. Calcd for C11H13NO2: C, 69.09; H, 6.85; N, 7.32. Found: C,
68.84; H, 6.71; N, 7.18.
Isopropyl Acetoacetate (3e)
Following the general procedure on a 5 mmol scale gave 3e as a vis-
cous oil; yield: 0.71 g (98%).
N-Cyclohexylacetoacetamide (3j)
Following the general procedure on a 5 mmol scale gave 3j as a
pale-yellow solid; yield: 0.90 g (98%); mp 76–77 °C.
IR (neat, NaCl): 2984.9, 2939.9, 1742.0, 1715.2, 1641.9, 1273.1,
1107.3 cm–1.
1H NMR (250 MHz, CDCl3): d = 1.27 (d, J = 6.3 Hz, 6 H), 2.27 (s,
3 H), 3.42 (s, 2 H), 5.05 (sept, J = 6.3 Hz, 1 H).
13C NMR (63 MHz, CDCl3): d = 21.9, 30.3, 50.6, 69.1, 166.9,
201.1.
IR (neat, NaCl): 3295.9, 3076.1, 2932.9, 2855.6, 1721.6, 1644.0,
1555.6, 1359.3, 1159.8 cm–1.
1H NMR (250 MHz, CDCl3): d = 1.12–1.46 (m, 5 H), 1.57–1.76 (m,
3 H), 1.87–1.92 (m, 2 H), 2.28 (s, 3 H), 3.40 (s, 2 H), 3.74–3.85 (m,
1 H), 6.87 (br s, 1 H).
Anal. Calcd for C7H12O3: C, 58.32; H, 8.39. Found: C, 58.02; H,
8.29.
13C NMR (63 MHz, CDCl3): d = 25.1, 25.8, 31.1, 33.1, 48.6, 50.6,
165.1, 204.9.
Synthesis 2010, No. 6, 1053–1057 © Thieme Stuttgart · New York