Subscribe to RSS
DOI: 10.1055/s-2002-34209
Michael Addition of Nitroalkanes to Dimethyl Citraconate, with DBU as Base: An Unexpected, One-Pot Synthesis of Polyfunctionalized Carbonyl Derivatives
Publication History
Publication Date:
23 September 2002 (online)
![](https://www.thieme-connect.de/media/synlett/200210/lookinside/thumbnails/10.1055-s-2002-34209-1.jpg)
Abstract
Michael addition of nitroalkanes to dimethyl citraconate, with DBU as base, allows the one pot formation of keto diesters. The reaction proceeds through an equilibrium form of the acceptor, followed by Michael addition of the nitroalkane and then, in situ Nef conversion.
Key words
DBU - Nef reaction - keto esters - nitroalkanes - dimethyl citraconate
- 1
Ballini R.Rinaldi A. Tetrahedron Lett. 1994, 35: 9247 - 2
Ballini R.Bosica G. Tetrahedron 1995, 51: 4213 - 3
Ballini R.Marcantoni E.Perella S. J. Org. Chem. 1999, 64: 2954 - 4
Ballini R.Bosica G.Damiani M.Righi P. Tetrahedron 1999, 55: 13451 - 5
Ballini R.Bosica G.Masè A.Petrini M. Eur. J. Org. Chem. 2000, 2927 - 6
Ballini R.Bosica G.Fiorini D.Gil MV.Petrini M. Org. Lett. 2001, 3: 1265 - 7
Ballini R.Bosica G.Fiorini D.Righi P. Synthesis 2002, 681 - 9 Recently we found that treatment
of secondary nitroalkanes with DBU proceeds through the Nef conversion
of the nitro groups to ketones:
Ballini R.Bosica G.Fiorini D.Petrini M. Tetrahedron Lett. 2002, 43: 5233 - 10
Hall N. Science 1994, 266: 32 -
11a
Fujimura T.Aoki S.Nakamura E. J. Org. Chem. 1991, 56: 2809 -
(b)
Cardillo G.Orena M.Porzi G.Sandri S.Tomasini C. J. Org. Chem. 1984, 49: 701 ; and references cited therein -
11c
Ravid V.Iverstein RM.Smith LR. Tetrahedron 1978, 34: 1449 -
11d
May WA.Peterson RS.Chang SS. J. Food Sci. 1978, 43: 1248 -
11e
Edwards ML.Bambury RE.Ritter HW. J. Med. Chem. 1976, 19: 330 -
11f
Naoshima Y.Ozawa H.Xondo H.Hayashi S. Agric. Biol. Chem. 1983, 47: 1431 - 12
Harrowven DC.Poon HS. Tetrahedron Lett. 1996, 37: 4281
References
PM3 semiempirical calculations by using the Gaussian 94W package showed that 9 is more stable than 6 by 2.0 kcal/mol. Gaussian 98 (Revision A.7): Frisch M. J., Trucks G. W., Schlegel H. B., Scuseria G. E., Robb M. A., Cheeseman J. R., Zakrzewski V. G., Montgomery J. A. Jr., Stratmann R. E., Burant J. C., Dapprich S., Millam J. M., Daniels A. D., Kudin K. N., Strain M. C., Farkas O., Tomasi J., Barone V., Cossi M., Cammi R., Mennucci B., Pomelli C., Adamo C., Clifford S., Ochterski J., Petersson G. A., Ayala P. Y., Cui Q., Morokuma K., Malick D. K., Rabuck A. D., Raghavachari K., Foresman J. B., Cioslowski J., Ortiz J. V., Baboul A. G., Stefanov B. B., Liu G., Liashenko A., Piskorz P., Komaromi I., Gomperts R., Martin R. L., Fox D. J., Keith T., Al-Laham M. A., Peng C. Y., Nanayakkara A., Gonzalez C., Challacombe M., Gill P. M. W., Johnson B., Chen W., Wong M. W., Andres J. L., Gonzalez C., Head-Gordon M., Replogle E. S., Pople J. A.; Gaussian 98 (Revision A.7); Gaussian, Inc.: Pittsburgh PA, 1998;
13Selected analytical data for the compounds 8h,i.
8h: IR: 3412, 1738 cm-1; 1H
NMR (CDCl3): δ = 1.3-1.6 (m, 6
H), 2.42 (bt, 2 H, J = 7.0 Hz),
2.56 (dd, 1 H, J = 16.6 and 6.7
Hz), 2.62 (dd, 1 H, J = 17.7
and 6.1 Hz), 2.68 (dd, 1 H,
J = 16.5
and 6.4 Hz), 2.91 (dd, 1 H, J = 18.0
and 7.0 Hz), 3.2-3.3 (m, 1 H), 3.6-3.7 (m, 2 H),
3.65 (s, 3 H), 3.66 (s, 3 H); 13C NMR
(CDCl3): δ = 23.3, 25.2, 32.4, 35.1,
36.3, 42.7, 43.1, 51.9, 52.2, 62.5, 172.0, 174.1, 208.3; MS (EI,
70 eV)
m/z 278 (M+ + 4),
257, 243, 187, 170, 127 (100%), 69, 55, 41, 31.
8i: IR: 1741 cm-1; 1H
NMR (CDCl3): δ = 2.14 (s, 3 H), 2.56 (dd,
1 H, J = 16.8 and 6.3 Hz), 2.6-2.8
(m, 6 H), 2.96 (dd, 1 H, J = 18.6
and 6.6 Hz), 3.2-3.3 (m, 1 H), 3.65 (s, 3 H), 3.66 (s,
3 H); 13C NMR (CDCl3): δ = 30.3,
35.5, 36.6, 36.8, 37.4, 43.6, 52.3, 52.7, 172.5, 174.5, 207.2, 207.4;
MS (EI, 70 eV) m/z 259 (M+ + 1),
226, 187, 127, 99 (100%), 59, 43, 29.