8972
T. Kumagai et al. / Tetrahedron 66 (2010) 8968e8973
126.87, 39.35, 35.08; IR (KBr)
n
2935w, 1631s, 1578m, 1506m,
residue was charged with a column chromatography (silica gel,
30 g) to give 3 from a hexane/CH2Cl2 elution as yellow solid;
254 mg (78%). The spectral data of 3, 28e32, and 34 were consistent
with the reported ones.
1483m, 1447m, 1396s, 1265m, 1085m, 1074m, 791m, 716m, 700m,
638m cmꢁ1; MS (EI) m/z (rel intensity) 149 (Mþ, 23), 148 [(Mꢁ1)þ,
49], 105 ([MꢁNMe2]þ, 100).
4.2.6. N,N-Dimethyl-4-dimethylaminobenzamide 1810. Yield (34%).
4.3.1. N,N-Diethylbanzamide 2822
ppm 7.40e7.34 (m, 5H), 3.55 (br s, 2H), 3.25 (br s, 2H), 1.25 (br s,
. d/
1H NMR (500 MHz, CDCl3)
Colorless solid; 89e90 ꢀC; 1H NMR (500 MHz, CDCl3)
d
/ppm
7.39e7.36 (m, AA00BB00, 2H), 6.68e6.65 (m, AA0BB0, 2H), 3.07 (s, 6H),
2.99 (s, 6H); 13C NMR (67.8 MHz, CDCl3)
172.06, 151.25, 129.19,
122.94, 110.97, 40.13, 38.53; IR (KBr) 2903w, 1611s, 1495m, 1385s,
3H), 1.10 (br s, 3H); IR (KBr)
n 2974w, 1630s, 1429m, 1288m,
d
706m cmꢁ1; MS (EI) m/z (rel intensity) 177 (Mþ, 21), 176 [(Mꢁ1)þ,
n
42], 105 ([MꢁN(C2H5)2]þ, 100).
1367s, 1269m, 1232m, 1188m, 1172m, 1083m, 1066m, 845m, 822m,
765m cmꢁ1; MS (EI) m/z (rel intensity) 192 (Mþ, 37), 148 ([Mꢁ
NMe2]þ, 100).
. d/ppm
4.3.2. N-Benzoylpiperidine 2923 1H NMR (500 MHz, CDCl3)
7.39 (m, 5H), 3.71 (br s, 2H), 3.34 (br s, 2H), 1.68e1.51 (m, 6H); IR
(KBr)
n 2937w, 2856w, 1634s, 1434m, 1277m, 1111m, 1001m,
4.2.7. N,N,N0,N0-Tetramethylisophthalamide 1912. Yield (71%). Color-
708m cmꢁ1; MS (EI) m/z (rel intensity) 189 (Mþ, 38), 188 [(Mꢁ1)þ,
less crystals: mp 92e93 ꢀC; 1H NMR (270 MHz, CDCl3)
d
7.46 (br s,
4H), 3.11 (br s, 6H), 2.97 (br s, 6H); 13C NMR (67.8 MHz, CDCl3)
170.66, 136.35, 128.45, 128.03, 125.48, 39.43, 35.24; IR (KBr)
99], 105 ([MꢁN(CH2)5]þ, 100).
d
n
4.3.3. 1,2-Di(4-tert-butylphenyl)ethane-1,2-dione 317. Yellow solid;
2935m, 1627s, 1502m, 1397s, 1256m, 1203w, 1074m, 920w, 823m,
740m, 636m cmꢁ1; MS (EI) m/z (rel intensity) 220 (Mþ, 25),176 ([Mꢁ
NMe2]þ, 100).
104e104.5 ꢀC; 1H NMR (270 MHz, CDCl3);
d
/ppm 7.93e7.88 (m,
AA00BB00, 4H), 7.53e7.49 (m, AA0BB0, 4H), 1.34 (s, 18H); 13C NMR
(100 MHz, CDCl3) /ppm 31.05, 35.44,125.90, 129.81, 130.56, 158.75,
194.35; IR (KBr,
/cmꢁ1) 3056 (w), 3037 (w), 2961 (s), 2904 (m), 2870
d
n
4.2.8. N,N,N0,N0-Tetramethylterephthalamide 2013. Yield (71%). Col-
(m), 1682 (s), 1661 (s), 1602 (s), 1566 (m), 1475 (m), 1410 (m), 1394
(w),1224 (s),1178 (s),1108 (s),1026 (w), 896 (s), 852 (s), 773 (m); MS
(EI) m/z (rel intensity) 322 [Mþ, 1], 161 (100), 146 (9), 118 (15).
orless crystals: mp 145e146 ꢀC; 1H NMR (270 MHz, CDCl3)
d
7.45 (s,
4H), 3.12 (br s, 6H), 2.97 (br s, 6H); 13C NMR (67.8 MHz, CDCl3)
170.60, 137.20, 126.87, 39.23, 35.08; IR (KBr) 2935m, 1630s,
d
n
1526m, 1478m, 1400s, 1266m, 1228w, 1088m, 858m, 736m,
599m cmꢁ1; MS (EI) m/z (rel intensity) 220 (Mþ, 29), 176 ([Mꢁ
NMe2]þ, 100).
4.3.4. 1,2-Diphenylethane-1,2-dione (benzil) 309a. Yield (14% from
15, 64% from 16, 70% from 17, 13% from 28, and 10% from 29). Yellow
solid; 94e95 ꢀC; 1H NMR (270 MHz, CDCl3) /ppm 7.97 (m, AA00BB0C,
d
4H), 7.65 (m, AA0BB00C, 2H), 7.52 (AA0BB0C, 4H).
4.2.9. N,N-Dimethyl-2-naphthcarbamide 216. Yield (89%). Colorless
solid; 82e83 ꢀC; 1H NMR (500 MHz, CDCl3)
d
/ppm 7.91e7.84 (m,
4H), 7.55e7.50 (m, 3H), 3.16 (s, 3H), 3.03 (s, 3H); 13C NMR
(125.8 MHz, CDCl3) /ppm 171.65, 133.66, 133.61, 132.68, 128.40,
128.20, 127.80, 127.00, 126.86, 126.64, 125.48, 39.43, 35.24; IR (KBr)
4.3.5. 1,2-Bis(4-N,N-dimethlyaminophenyl)ethane-1,2-dione
3118. Yield (69%). Yellow solid; 202e203 ꢀC; 1H NMR (270 MHz,
d
CDCl3) d
/ppm 7.88e7.82 (m, AA00BB0, 4H), 7.68e7.62 (m, AA0BB0, 4H),
3.06 (s, 12H).
n
3026 w, 2935w, 1616s, 1572m, 1501s, 1468m, 1410s, 1276m,
1259m, 1182m, 1126m, 1076s, 872m, 824s, 779m, 761s cmꢁ1; MS
(EI) m/z (rel intensity) 199 (Mþ, 399), 155 ([MꢁNMe2]þ, 100) 127
([MꢁCONMe2]þ, 84).
4.3.6. 4-Cyanobenzaldehyde 3219. Yield (11%). Yellow solid;
99e100 ꢀC; 1H NMR (270 MHz, CDCl3)
d/ppm 10.10 (s, 1H),
8.01e7.98 (m, AA00BB0, 2H), 7.86e7.83 (m, AA0BB0, 2H).
4.2.10. N,N-Dimethyl-1-adamantanecarboxamide 2214. Yield (71%).
4.3.7. 1,2-Di(2-naphthyl)ethane-1,2-dione 3420. Yield (18%) to-
gether with 48% of recovery, 21. Yellow solid; 156e157 ꢀC; 1H
Colorless solid; 1H NMR (500 MHz, CDCl3)
d
/ppm 3.07 (s, 6H), 2.02
(m, 9H), 1.69 (m, 6H); IR (KBr)
n
2901s, 2848m, 1614s, 1497m,
NMR (270 MHz, CDCl3)
d
/ppm 8.46 (s, 1H), 8.15 (dd, J¼8.9, 1.6 Hz,
1452m, 1383s, 1163m, 1057m, 650m cmꢁ1; MS (EI) m/z (rel in-
1H), 8.00e7.89 (m, 3H), 7.65 (dt, J¼7.6, 1.3 Hz, 1H), 7.55 (dt, J¼7.3,
tensity) 207 (Mþ, 29), 135 ([MꢁCONMe2]þ, 100).
1.3 Hz, 1H).
4.2.11. N,N-Dimethyl-isonicotincarboxamide 2315. Yield (42%). Col-
Acknowledgements
orless solid; 57e58 ꢀC; 1H NMR (270 MHz, CDCl3)
d/ppm 8.70e8.68
(m, AA00BB00, 2H), 7.31e7.29 (m, AA0BB0, 2H), 3.13 (br s, 3H), 2.95
(br s, 3H).
This was supported by a Grant-in-Aid for Scientific Research on
Innovative Areas (No. 21108521 A01, ‘pi-Space’) from the Ministry
of Education, Culture, Sports, Science and Technology, Japan.
4.3. General procedure for alkali metal reduction of N,N-
dialkylamides
Supplementary data
In a 50 ml of two-necked round-bottomed flask equipped with
a N2 balloon and a rubber septum was charged with N,N-dimethyl-
4-tert-butylbanzamide 2 (417 mg, 2.03 mmol), 4,40-di-tert-butyl-
biphenyl (89 mg, 0.33 mmol), granuler lithium (ALDRICH, granule
99.9þ%, 74 mg, 10.7 mmol), and a stirrer bar. The flask was purged
with N2, and THF (10 ml) was added via syringe. The solution was
sonicated in an ice-water bath. The color of the solution gradually
changed yellow, brown and black for 45 min. Upon 1 h irradiation,
the reaction mixture was poured into an ice-cold hydrochloric acid
(50 ml). The mixture was extracted with ethyl acetate (50 ml). The
organic layer was separated, washed with water and brine, and
dried over anhydrous Na2SO4. Upon evaporation of the solvent, the
Supplementary data associated with this article can be found in
References and notes
1. For reviews see, (a) Wakefield, B. J. The Chemistry of Organolithium Compounds;
Pergamon: Oxford, 1974; (b) Wakefield, B. J. Organolithium Methods; Academic:
London, 1988, pp 82e88.
2. (a) Kurata, H.; Ekinaka, T.; Kawase, T.; Oda, M. Tetrahedron Lett. 1993, 34,
3445e3448; (b) Kawase, T.; Kurata, H.; Morikawa, T.; Oda, M. Tetrahedron Lett.
1993, 34, 3449e3452.
3. The similar reactions using N,N-dimethylaminoalkoxides were reported by
Turos’ and Hwu’s groups. (a) Turos, E.; Boy, K.; Ren, X.-F. J. Org. Chem. 1992, 57,