Preparation of δ-Chloro-R-allenyl Ketones
J . Org. Chem., Vol. 61, No. 19, 1996 6683
(s), 102.4 (s), 98.5 (d), 64.7 (t), 57.5 (d), 26.8 (q), 20.5 (q), 14.4
(q). Minor isomer: 1H NMR (CDCl3) δ 5.77 (br s, 1H), 4.59
(dd, J ) 14.0, 7.5 Hz, 1H), 4.30 (m, 2H), 2.20 (s, 3H), 2.05 (s,
3H), 1.93 (d, J ) 2.7 Hz); 13C NMR (CDCl3) δ 211.2 (s), 197.7
(s), 170.0 (s), 102.4 (s), 98.7 (d), 64.9 (t), 54.6 (d), 26.8 (q), 20.5
(q), 14.6 (q). Anal. Calcd for C10H13O3Cl: C, 55.44; H, 6.05;
Cl, 16.36. Found: C, 55.55; H, 6.09; Cl, 16.28.
(3Z,5E)-7-Acetoxy-4-ch lor o-5-m eth yl-3,5-h ep ta d ien -2-
on e (9): IR 1740, 1685, 1234 cm-1; 1H NMR (CDCl3, 200 MHz)
δ 6.38 (s, 1H), 6.35 (t, J ) 6.4 Hz, 1H), 4.70 (d, J ) 6.4 Hz,
2H), 2.33 (s, 3H), 2.00 (s, 3H), 1.86 (s, 3H); 13C NMR (CDCl3)
δ 196.9 (s), 170.4 (s), 142.3 (s), 134.7 (s), 130.5 (d), 124.0 (d),
61.1 (t), 31.6 (q), 20.5 (q), 14.6 (q).
Acyla tion of 1-Acetoxy-2-h exen -4-yn e (5c) w ith Acetyl
Ch lor id e. 7-Acetoxy-6-ch lor o-3-m eth yl-3,4-h ep ta d ien -2-
on e (6c). Unseparable 8:1 mixture of diastereomers: IR 1951,
1741, 1681, 1230 cm-1; 1H NMR (CDCl3, 200 MHz) δ 5.66 (m;
1H), 4.63 (m, 1H), 4.28 (dd, J ) 5.47, 3.66 Hz, 2H), 2.24 (s,
3H), 2.02 (s, 3H), 1.73 (s, 3H). Major isomer: 13C NMR (CDCl3)
δ 212.9 (s), 204.4 (s), 170.7 (s), 96.7 (s), 93.7 (d), 66.5 (t), 54.6
(d), 27.0 (q), 20.6 (q), 18.1 (q). Minor isomer (in part): 13C
NMR (CDCl3) δ 212.7 (s), 93.8 (d), 26.8 (q). Anal. Calcd for
C10H13O3Cl: C, 55.44; H, 6.05; Cl, 16.36. Found: C, 55.59; H,
5.98; Cl, 16.46.
(3E,5E)-7-Acetoxy-4-ch lor o-3-m eth yl-3,5-h ep ta d ien -2-
on e (7c): 1H NMR (CDCl3, 200 MHz) δ 6.81 (d, J ) 15.0 Hz,
1H), 6.26 (dt, J ) 15.0, 4.9 Hz, 1H), 4.63 (d, J ) 4.9 Hz, 2H),
2.22 (s, 3H), 2.08 (s, 3H), 2.04 (s, 3H); 13C NMR (CDCl3) δ 201.7
(s), 170.2 (s), 136.1 (s), 134.5 (s), 130.8 (d), 127.3 (d), 63.7 (t),
29.8 (q), 20.8 (q), 13.2 (q).
110.1 (s), 100.1 (d), 56.6 (d), 47.9 (t), 41.3 (d), 39.9 (t), 30.7 (s),
27.6 (q), 27.4 (q)(3C), 27.0 (t). 13b: 1H NMR δ (in part) 5.82
(t, J ) 3.6 Hz, 1H), 4.30 (ddd, J ) 12.2, 4.6, 3.6 Hz, 1H), 2.58
(ddd, J ) 14.0, 3.7, 3.0 Hz, 1H), 2.14 (s, 3H), 0.84 (s, 9H). Anal.
Calcd for C14H21OCl: C, 69.84; H, 8.79; Cl, 14.72. Found: C,
69.75; H, 8.82; Cl, 14.81.
Acyla tion of 1-Eth yn ylcycloh exen e w ith Acetyl Ch lo-
r id e. 2-Ch lor o-1-(3-oxo-1-bu ten yliden e)cycloh exa n e (16a
a n d 17a ) was separated by flash chromatography on silica
gel: IR 1952, 1682, 1228 cm-1
.
16a : 1H NMR (CDCl3, 400
MHz) δ 5.67 (br d, J ) 3.0 Hz, 1H), 4.71 (t, J ) 4.2 Hz, 1H),
2.55 (dddd, J ) 14.2, 10.4, 4.1, 3.0 Hz, 1H), 2.17 (s, 3H), 2.0-
1.2 (m; 7H); 13C NMR (CDCl3) δ 208.2 (s), 199.3 (s), 107.2 (s),
97.6 (d), 58.0 (d), 35.3 (t), 26.1 (q), 25.9 (t), 25.3 (t), 20.6 (t);
Anal. Calcd for C10H13OCl: C, 65.04; H, 7.10; Cl, 19.20.
Found: C, 64.96; H, 7.08; Cl, 19.18. 17a : 1H NMR (CDCl3,
400 MHz) δ (in part) 5.67 (d, J ) 3.2 Hz, 1H), 4.66 (d, J ) 4.4
Hz, 1H), 2.49 (dddd, J ) 14.2, 10.4, 4.1, 3.2 (suppressed by
irradiation at 5.67 ppm) Hz, 1H), 2.11 (s, 3H), 2.0-1.2 (m; 7H);
13C NMR (CDCl3) δ 207.5 (s), 197.4 (s), 107.5 (s), 97.5 (d), 57.7
(d), 35.7 (t), 26.5 (t), 26.1 (q), 25.6 (t), 20.8 (t).
4-Ch lor o-4-(1-cycloh exen yl)-3-bu ten -2-on e (18a ): IR
1
1683 cm-1; H NMR (CDCl3, 200 MHz) δ 6.71 (t, J ) 3.3 Hz,
1H), 6.29 (s, 1H), 2.35 (s, 3H), 2.10 (br s, 4H), 1.68-1.42 (br s,
4H); 13C NMR (CDCl3) δ 197.7 (s), 143.6 (s), 136.3 (d), 133.5
(s), 121.4 (d), 32.1 (q), 26.3 (t), 26.0 (t), 22.4 (t), 21.5 (t).
Acyla tion of 1-Eth yn ylcycloh exen e w ith isobu tyr yl
Ch lor id e. 2-Ch lor o-1-(4-m eth yl-3-oxo-1-p en tylid en e)cy-
cloh exa n e (16b a n d 17b) was separated by flash chroma-
tography on silica gel: IR 1953, 1682 cm-1
.
16b: 1H NMR
Acyla tion of 1-Acetoxy-3-m eth yl-2-h exen -4-yn e (5d )
w ith Acetyl Ch lor id e. 7-Acetoxy-6-ch lor o-3,5-d im eth yl-
3,4-h ep t a d ien -2-on e (6d ). Unseparable 9:1 mixture of
(CDCl3, 200 MHz) δ 5.62 (d, J ) 3.0 Hz, 1H), 4.69 (t, J ) 4.0
Hz, 1H), 3.00 (sept, J ) 6.85 Hz, 1H), 2.60-2.46 (m, 1H), 2.26-
2.15 (m, 1H), 2.02-1.94 (m, 2H), 1.90-1.67 (m, 2H), 1.59-
1.44 (m, 2H), 1.01 (d, J ) 6.85 Hz, 3H), 0.98 (d, J ) 6.85 Hz,
3H); 13C NMR (CDCl3) δ 207.2 (s), 203.7 (s), 107.0 (s), 95.7 (d),
58.0 (d), 36.4 (d), 35.3 (t), 26.0 (t), 25.3 (t), 20.8 (t), 18.8 (q),
18.5 (q). 17b: 1H NMR (CDCl3, 200 MHz) δ 5.69 (br d, J )
3.12 Hz, 1H), 4.69 (t, J ) 4.0 Hz, 1H), 2.95 (sept, J ) 6.85 Hz,
1H), 2.51 (m, 1H), 2.18 (dt, J ) 14.1, 4.5 Hz, 1H), 1.99-1.92
(m, 2H), 1.899-1.64 (m, 2H), 1.57-1.18 (m, 2H), 1.06 (d, J )
6.85 Hz, 3H), 1.03 (d, J ) 6.85 Hz, 3H); 13C NMR (CDCl3) δ
207.9 (s), 204.3 (s), 107.4 (s), 95.6 (d), 57.7 (d), 36.5 (d), 35.7
(t), 26.3 (t), 25.7 (t), 20.8 (t), 18.6 (q) (2C). Anal. Calcd for
C12H17OCl: C, 67.76; H, 8.06; Cl, 16.67. Found: C, 67.80; H,
8.01; Cl, 16.72.
diastereomers: IR 1953, 1746, 1683, 1233 cm-1
.
Major
isomer: 1H NMR (CDCl3, 200 MHz) δ 4.58 (t, J ) 6.8 Hz, 1H),
4.26 (m, 2H), 2.20 (s, 3H), 2.01 (s, 3H), 1.87 (s, 3H), 1.71 (s,
3H); 13C NMR (CDCl3) δ 210.5 (s), 198.5 (s), 170.1 (s), 105.5
(s), 100.8 (s), 65.16 (t), 58.33 (d), 26.9 (q), 20.6 (q), 14.3 (q),
13.2 (q). Minor isomer: 1H NMR (CDCl3) δ 4.50 (t, J ) 7.0
Hz, 1H), 4.26 (m, 2H), 2.20 (s, 3H), 2.02 (s, 3H), 1.89 (s, 3H),
1.71 (s, 3H); 13C NMR (CDCl3) δ 210.5 (s), 198.5 (s), 170.1 (s),
105.5 (s), 100.8 (s), 65.19 (t), 58.28 (d), 26.9 (q), 20.6 (q), 14.3
(q), 13.2 (q). Anal. Calcd for C11H15O3Cl: C, 57.27; H, 6.55;
Cl, 15.37. Found: C, 57.16; H, 6.58; Cl, 15.30.
Acyla tion of 1-Acetoxy-2,3-d im eth yl-2-p en ten -4-yn e
(5e) w it h Acet yl Ch lor id e. 7-Acet oxy-6-ch lor o-5,6-d i-
m eth yl-3,4-h ep ta d ien -2-on e (6e): IR 1952, 1748, 1686, 1231
(4Z)-5-Ch lor o-5-(1-cycloh exen yl)-2-m et h yl-4-b u t en -3-
1
on e (18b). IR 1683 cm-1; H NMR (CDCl3, 200 MHz) δ 6.64
1
cm-1. Major isomer: H NMR (CDCl3, 200 MHz) δ 5.75 (q, J
(t, J ) 3.5 Hz, 1H), 6.33 (s, 1H), 2.70 (sept, J ) 6.9 Hz, 1H),
) 2.8 Hz, 1H), 4.24 (m, 2H), 2.16 (s, 3H), 2.01 (s, 3H), 1.92 (d,
J ) 2.8 Hz, 3H), 1.66 (s, 3H); 13C NMR (CDCl3) δ 211.1 (s),
197.0 (s), 169.9 (s), 107.3 (s), 99.2 (d), 68.6 (t), 67.5 (s), 26.5
(q), 26.4 (q), 20.6 (q), 14.6 (q). Anal. Calcd for C11H15O3Cl:
C, 57.27; H, 6.55; Cl, 15.37. Found: C, 57.20; H, 6.54; Cl,
15.41.
2.15 (br s, 4H), 1.9-1.3 (m, 4H), 0.88 (d, J ) 6.9 Hz, 6H); 13
C
NMR (CDCl3) δ 203.0 (s), 143.3 (s), 135.7 (d), 133.5 (s), 118.8
(d), 41.7 (d), 26.25 (t), 26.18 (t), 22.4 (t), 21.4 (t), 18.1 (q) (2C).
Differential nuclear Overhauser enhancement experiments
confirm the Z-configuration. By irradiation at 6.33 ppm,
enhancement was observed for signals at 2.70, 2.18, and 1.02
ppm.
2-(Acetoxym eth yl)-4-ch lor o-2,3,6-tr im eth yl-2H-p yr a n
(10): IR 1744, 1654, 1233 cm-1; 1H NMR (CDCl3, 200 MHz) δ
4.98 (br s, 1H), 4.33 (1/2 AB, J ) 11.8 Hz, 1H), 3.90 (1/2 AB,
J ) 11.8 Hz, 1H), 2.05 (s, 3H), 1.74 (s, 3H), 1.73 (s, 3H), 1.36
(s, 3H); 13C NMR (CDCl3) δ 170.9 (s), 151.9 (s), 124.6 (s), 118.6
(s), 100.8 (d), 81.7 (s), 64.9 (t), 30.0 (q), 20.8 (q), 17.0 (q), 14.3
(q).
Acyla tion of 4-ter t-Bu tyl-1-eth yn ylcycloh exen e (11)
w ith Acetyl Ch lor id e. (2Z)-4-Ch lor o-4-(4-ter t-bu tyl-1-
cycloh exen yl)-3-bu ten -2-on e (12): IR 1658, 1610 cm-1; 1H
NMR (CDCl3) δ 6.67 (br s, 1H), 6.24 (s, 1H), 2.30 (s, 3H), 0.78
(s, 9H); 13C NMR (CDCl3) δ 197.5 (s), 136.7 (d), 133.3 (s), 121.5
(d), 97.5 (s), 59.0 (s), 65.7 (t), 28.0 (t), 27.7 (t), 27.3 (q), 27.0 (q)
(3C).
cis-4-ter t-Bu t yl-2-ch lor o-1-(3-oxo-1-b u t en ylid en e)cy-
cloh exa n e (13). Unseparable 4:1 mixture of diastereomers:
IR 1951, 1682, 1235 cm-1. 13a : 1H NMR (CDCl3, 400 MHz)
δ 5.77 (t, J ) 4.0 Hz, 1H), 4.28 (ddd, J ) 12.1, 4.6, 4.0
(suppressed by irradiation at 5.77 ppm) Hz, 1H), 2.60 (ddd, J
) 14.0, 3.7, 3.0 Hz, 1H), 2.45-2.32 (m, 1H), 2.32-2.20 (m, 1H),
2.20 (s, 3H), 2.15-1.98 (m, 1H), 1.55-1.40 (m, 1H), 1.28-1.15
(m, 1H), 0.85 (s, 9H); 13C NMR (CDCl3) δ 208.1 (s), 199.0 (s),
Acyla tion of 1-Eth yn yl-2,6,6-tr im eth ylcycloh exen e (21)
w ith Acetyl Ch lor id e. 2,4,4-Tr im eth yl-3-(3-oxo-1-bu ten -
1
ylid en e)-1-cycloh exen e (22): IR 1936, 1682 cm-1; H NMR
(CDCl3, 200 MHz) δ 5.85 (br, s, 1H), 5.56 (t, J ) 2.7 Hz, 1H),
2.05 (s, 3H), 1.59 (br s, 3H), 1.40 (t, J ) 6.2 Hz, 2H), 1.01 (s,
3H), 0.96 (s, 3H); 13C NMR (CDCl3) δ 212.8 (s), 198.7 (s), 126.7
(d), 125.4 (s), 117.1 (s), 101.6 (d), 35.4 (t), 33.2 (s), 27.7 (q),
27.6 (q), 26.2 (q), 22.7 (t), 20.9 (q). Anal. Calcd for C13H18O:
C, 82.06; H, 9.53. Found: C, 81.98; H, 9.49.
4-Ch lor o-4-(2,6,6-tr im eth yl-1-cycloh exen yl)-3-bu ten -2-
on e (23): IR 1699 cm-1; 1H NMR (CDCl3, 200 MHz) δ 6.45 (s,
1H), 2.08 (s, 3H), 1.98 (t, J ) 5.92 Hz, 2H), 1.73-1.50 (m, 2H),
1.57 (s, 3H), 1.42 (t, J ) 4.88 Hz, 2H), 1.12 (s, 3H), 0.89 (s,
3H); 13C NMR (CDCl3) δ 195.1 (s), 149.5 (s), 134.9 (s), 130.6
(s), 129.8 (d), 39.0 (t), 34.4 (s), 31.4 (t), 30.2 (q), 29.8 (q), 27.7
(q), 21.1 (q), 18.5 (t). Anal. Calcd for C13H19OCl: C, 68.86;
H, 8.45; Cl, 15.64. Found: C, 68.79; H, 8.40; Cl, 15.70.
Hyd r olysis of δ-Ch lor o-r-a llen yl k eton es 16 a n d 17. To
a stirred suspension of CaCO3 (4 g) in acetone (100 mL) and
water (60 mL) was added chloro ketone (20 mmol). The
suspension was submitted to reflux for 30 h. After that time,