4252
P.-Q. Huang et al. / Tetrahedron 71 (2015) 4248e4254
1a: Colorless oil. IR (film) nmax: 2932, 2860, 1716, 1466, 1260,
1129 cmꢀ1; 1H NMR (400 MHz, CDCl3)
699 cmꢀ1
;
1H NMR (400 MHz, CDCl3)
d
0.88 (t, J¼7.3 Hz, 3H),
d
0.88 (t, J¼6.9 Hz, 3H), 0.90
1.24e1.34 (m, 2H), 1.49e1.59 (m, 2H), 2.38 (t, J¼7.4 Hz, 2H), 2.72 (t,
(t, J¼7.4 Hz, 3H), 1.22e1.35 (m, 18H), 1.50e1.60 (m, 4H), 2.38 (t,
J¼7.6 Hz, 2H), 2.89 (t, J¼7.6 Hz, 2H), 7.15e7.31 (m, 5H) ppm; 13C
J¼7.4 Hz, 2H), 2.39 (t, J¼7.4 Hz, 2H) ppm; 13C NMR (100 MHz, CDCl3)
NMR (100 MHz, CDCl3)
d 13.8, 22.3, 25.8, 29.7, 42.7, 44.2, 126.0,
d
13.8, 14.1, 22.3, 22.6, 23.9, 26.0, 29.3, 29.3, 29.4, 29.4, 29.6 (2C),
128.3 (2C), 128.4 (2C), 141.1, 210.3 ppm; MS (ESI) m/z 213 (MþNaþ,
31.9, 42.5, 42.8, 211.6 ppm; MS (ESI) m/z 263 (MþNaþ, 100%).
Dibenzylamine (6a). Pale yellow oil. IR (film) nmax: 3332, 3083,
100%).
3061, 3024, 2917, 2817, 1494, 1452, 1109, 1027 cmꢀ1
;
1H NMR
4.2.7. Propiophenone (1g). Following the general procedure, the
reaction of amide 5k (149 mg, 1.0 mmol) with EtMgBr gave, after
flash column chromatography on silica gel (eluent: EtOAc/n-
hexane¼1/50), the known ketone 1g (100 mg, yield: 75%). Colorless
(400 MHz, CDCl3)
d 1.68 (br s, 1H), 3.80 (s, 4H), 7.19e7.40 (m, 10H)
ppm; 13C NMR (100 MHz, CDCl3)
d 53.2 (2C), 127.0 (2C), 128.2 (4C),
128.4 (4C), 140.4 (2C) ppm; MS (ESI) m/z 198 (MþHþ, 100%).
oil. IR (film) nmax: 3081, 2921, 2851, 1691, 1261, 746, 699 cmꢀ1 1H
;
4.2.2. Tetradecan-3-one (1b). Following the general procedure, the
reaction of amide 5a (380 mg, 1.0 mmol) with EtMgBr gave, after
flash column chromatography on silica gel (eluent: EtOAc/n-
hexane¼1/50), the known ketone 1b34a (172 mg, yield: 81%). Col-
orless oil. IR (film) nmax: 2924, 2853, 1716, 1462, 1376, 1108 cmꢀ1; 1H
NMR (400 MHz, CDCl3)
d
1.23 (t, J¼7.2 Hz, 3H), 3.00 (q, J¼7.2 Hz,
2H), 7.42e7.49 (m, 2H), 7.52e7.58 (m, 1H), 7.94e8.00 (m, 2H) ppm;
13C NMR (100 MHz, CDCl3)
d 8.2, 31.7, 127.9 (2C), 128.5 (2C), 132.8,
136.9, 200.8 ppm; MS (ESI) m/z 157 (MþNaþ, 100%).
NMR (400 MHz, CDCl3)
d
0.88 (t, J¼6.8 Hz, 3H),1.05 (t, J¼7.3 Hz, 3H),
4.2.8. 1-(2-Thienyl)-1-pentanone (1h). Following the general pro-
cedure, the reaction of amide 5m (155 mg, 1.0 mmol) with n-
BuMgBr gave, after flash column chromatography on silica gel (el-
uent: EtOAc/n-hexane¼1/50), the known ketone 1h10b (132 mg,
yield: 79%). Colorless oil. IR (film) nmax: 3091, 2958, 2931, 2872,
1.22e1.34 (m, 16H), 1.52e1.62 (m, 2H), 2.39 (t, J¼7.3 Hz, 2H), 2.43 (t,
J¼7.3 Hz, 2H) ppm; 13C NMR (100 MHz, CDCl3)
d 7.8, 14.1, 22.7, 23.9,
29.3, 29.3, 29.4, 29.5, 29.6 (2C), 31.9, 35.8, 42.4, 212.0 ppm; MS (ESI)
m/z 235 (MþNaþ, 100%).
1661, 1519, 1416, 1264, 722 cmꢀ1; 1H NMR (400 MHz, CDCl3)
d 0.95
4.2.3. 1-Phenylpentadecan-4-one (1c). Following the general pro-
cedure, the reaction of amide 5a (380 mg, 1.0 mmol) with (3-
phenylpropyl)magnesium bromide gave, after flash column chro-
matography on silica gel (eluent: EtOAc/n-hexane¼1/50), ketone 1c
(250 mg, yield: 83%). Colorless oil. IR (film) nmax: 3085, 3062, 3027,
(t, J¼7.4 Hz, 3H), 1.36e1.46 (m, 2H), 1.69e1.78 (m, 2H), 2.89 (t,
J¼7.4 Hz, 2H), 7.12 (dd, J¼5.0, 3.8 Hz, 1H), 7.62 (dd, J¼5.0, 1.1 Hz, 1H),
7.71 (dd, J¼3.8, 1.1 Hz, 1H) ppm; 13C NMR (100 MHz, CDCl3)
d 13.8,
22.4, 26.9, 39.1, 128.0, 131.6, 133.2, 144.5, 193.5 ppm; MS (ESI) m/z
191 (MþNaþ, 100%).
2925, 2854, 1715, 1496, 1454, 1370, 746, 699 cmꢀ1
(400 MHz, CDCl3)
;
1H NMR
d
0.88 (t, J¼6.9 Hz, 3H), 1.22e1.33 (m, 16H),
4.2.9. (E)-1-Phenylpent-1-en-3-one (1i). Following the general
procedure, the reaction of amide 5n (175 mg, 1.0 mmol) with
EtMgBr gave, after flash column chromatography on silica gel (el-
uent: EtOAc/n-hexane¼1/50), the known ketone 1i34d (123 mg,
yield: 77%). Colorless oil. IR (film) nmax: 3081, 3063, 3029, 2926,
1.49e1.58 (m, 2H), 1.90 (tt, J¼7.4, 7.4 Hz, 2H), 2.35 (t, J¼7.4 Hz, 2H),
2.40 (t, J¼7.4 Hz, 2H), 2.61 (t, J¼7.4 Hz, 2H), 7.15e7.32 (m, 5H) ppm;
13C NMR (100 MHz, CDCl3)
d 14.1, 22.7, 23.8, 25.2, 29.2, 29.3, 29.4,
29.4, 29.6 (2C), 31.9, 35.1, 41.8, 42.9, 125.9, 128.3 (2C), 128.4 (2C),
141.6, 211.1 ppm; MS (ESI) m/z 325 (MþNaþ, 100%); HRESIMS calcd
for [C21H34NaO]þ (MþNaþ): 325.2502; found: 325.2509.
2851, 1694, 1671, 1449, 751, 690 cmꢀ1 1H NMR (400 MHz, CDCl3)
;
d
1.17 (t, J¼7.3 Hz, 3H), 2.70 (q, J¼7.3 Hz, 2H), 6.75 (d, J¼16.2 Hz, 1H),
7.36e7.42 (m, 3H), 7.51e7.60 (m, 3H) ppm; 13C NMR (100 MHz,
4.2.4. 5-Phenylpentan-2-one (1d). Following the general pro-
cedure, the reaction of amide 5i (239 mg, 1.0 mmol) with (3-
phenylpropyl)magnesium bromide gave, after flash column chro-
matography on silica gel (eluent: EtOAc/n-hexane¼1/50), the
known ketone 1d34c (114 mg, yield: 70%). Colorless oil. IR (film)
nmax: 3086, 3062, 3026, 2931, 2860, 1715, 1496, 1453, 1366, 747,
CDCl3) d 8.2, 34.0, 126.1, 128.2 (2C), 128.9 (2C), 130.3, 134.6, 142.2,
200.8 ppm; MS (ESI) m/z 183 (MþNaþ, 100%).
4.2.10. 4-Pentanoylbenzonitrile (1j). Following the general pro-
cedure, the reaction of amide 5o (174 mg,1.0 mmol) with n-BuMgBr
gave, after flash column chromatography on silica gel (eluent:
EtOAc/n-hexane¼1/50), the known ketone 1j34e (125 mg, yield:
67%).
Following the general procedure, the reaction of amide 5h
(281 mg, 1.0 mmol) with Knochel-Grignard reagent 8 gave, after
flash column chromatography on silica gel (eluent: EtOAc/n-
hexane¼1/50), the known ketone 1j (121 mg, yield: 65%) and
dibenzylamine 6a (126 mg, yield: 64%).
700 cmꢀ1
2.11 (s, 3H), 2.43 (t, J¼7.5 Hz, 2H), 2.62 (t, J¼7.5 Hz, 2H), 7.15e7.31
(m, 5H) ppm; 13C NMR (100 MHz, CDCl3)
25.2, 29.9, 35.0, 42.8,
;
1H NMR (400 MHz, CDCl3)
d
1.91 (tt, J¼7.5, 7.5 Hz, 2H),
d
125.9, 128.4 (2C), 128.4 (2C), 141.5, 208.7 ppm; MS (ESI) m/z 185
(MþNaþ, 100%).
4.2.5. 1-Phenylpentan-3-one (1e). Following the general procedure,
the reaction of amide 5j (329 mg,1.0 mmol) with EtMgBr gave, after
flash column chromatography on silica gel (eluent: EtOAc/n-
hexane¼1/50), the known ketone 1e34b (119 mg, yield: 73%). Col-
orless oil. IR (film) nmax: 3085, 3055, 3027, 2957, 2923, 2851, 1717,
Colorless oil. IR (film) nmax: 3062, 3037, 2926, 2855, 2233, 1576,
1494, 699 cmꢀ1; 1H NMR (400 MHz, CDCl3)
d
0.96 (t, J¼7.3 Hz, 3H),
1.37e1.46 (m, 2H), 1.69e1.77 (m, 2H), 2.98 (t, J¼7.3 Hz, 2H),
7.75e7.79 (m, 2H), 8.02e8.06 (m, 2H) ppm; 13C NMR (100 MHz,
1496,1455,1261, 746, 699 cmꢀ1; 1H NMR (400 MHz, CDCl3)
d
1.04 (t,
CDCl3) d 13.8, 22.3, 26.1, 38.6, 116.2, 117.9, 128.4 (2C), 132.5 (2C),
J¼7.4 Hz, 3H), 2.40 (q, J¼7.4 Hz, 2H), 2.73 (t, J¼7.6 Hz, 2H), 2.90 (t,
140.0, 199.0 ppm; MS (ESI) m/z 210 (MþNaþ, 100%).
J¼7.6 Hz, 2H), 7.15e7.31 (m, 5H) ppm; 13C NMR (100 MHz, CDCl3)
d
7.7, 29.8, 36.1, 43.9, 126.0, 128.3 (2C), 128.5 (2C), 141.2, 210.6 ppm;
4.2.11. 1-(4-Bromophenyl)pentan-1-one (1k). Following the general
procedure, the reaction of amide 5p (227 mg, 1.0 mmol) with n-
BuMgBr gave, after flash column chromatography on silica gel (el-
uent: EtOAc/n-hexane¼1/50), the known ketone 1k10b (170 mg,
yield: 71%). Colorless oil. IR (film) nmax: 2958, 2932, 2872, 1687,
MS (ESI) m/z 185 (MþNaþ, 100%).
4.2.6. 1-Phenylheptan-3-one (1f). Following the general procedure,
the reaction of amide 5j (329 mg, 1.0 mmol) with n-BuMgBr gave,
after flash column chromatography on silica gel (eluent: EtOAc/n-
hexane¼1/50), the known ketone 1f34b (143 mg, yield: 75%) and
1586, 1396, 1204, 1071, 1007, 836, 807 cmꢀ1
CDCl3)
2.93 (t, J¼7.3 Hz, 2H), 7.57e7.61 (m, 2H), 7.79e7.84 (m, 2H) ppm;
13C NMR (100 MHz, CDCl3)
13.9, 22.4, 26.3, 38.2, 127.9, 129.5 (2C),
;
1H NMR (400 MHz,
d
0.95 (t, J¼7.3 Hz, 3H), 1.35e1.45 (m, 2H), 1.66e1.75 (m, 2H),
dibenzylamine 6a (153 mg, yield: 78%). Colorless oil. IR (film) nmax
:
3085, 3063, 3028, 2958, 2932, 2872, 1714, 1496, 1454, 1370, 748,
d