best of our knowledge, the enantioselective synthesis of
sulfamate-fused 2,6-disubstituted piperidines-4-ones are
rarely reported. Consequently, the development of effi-
cient methods to access these valuable compounds is an
attractive goal.
employed in the aminocatalyzed [4 þ 2] cycloaddition
8
,9
reactions of imines. Very recently, Jacobsen reported
the primary aminothiourea-catalyzed cycloaddition of en-
one and cyclic imine, affording high enantioselective in-
9
c
dolo- and benzoquinolizidine.
Inspired by our interest in the amino-catalyzed addition
1
0
reaction, we surmised that the enamine formed in situ from
enones or ynones might react with cyclic N-sulfonylimines in
1
1
Scheme 1. [4 þ 2] Cycloaddition Reaction between Imines and
the presence of primary amine, providing a concise route to
valuable sulfamate-fused 2,6-disubstituted piperidin-4-ones
or2,3-dihydropyridin-4(1H)-ones(Scheme1, b and c). The
primary amine-catalyzed cycloaddition between cyclic
Unsaturated Ketones
1
2,13
N-sulfonylimines and ynones
has never been reported
to date. Prominent features of this reaction include a
Mannich/reflexive-Michael/protonation reaction sequen-
ce via enamineꢀiminiumꢀallenic enamineꢀiminium cas-
1
4ꢀ16
cade catalysis. The chiral allenamine intermediate
would be formed in situ and then act as the nucleophile
in a subsequent reaction (Scheme 1, c).
Initially, we explored the [4 þ 2] cycloaddition reaction
of benzoxathiazine-2,2-dioxide 2a and (E)-4-phenylbut-
3-en-2-one 3a in toluene at 40 °C in the presence of
o-fluorobenzoic acid (A1) by using 20 mol % chiral
primary amines catalyst 1, which was derived from natural
(
10) (a) Liu, Q.-Z.; Wang, X.-L.; Luo, S.-W.; Zheng, B.-L.; Qin,
D.-B. Tetrahedron Lett. 2008, 49, 7434. (b) Deng, Y.-H.; Chen, J.-Q.; He,
L.; Kang, T.-R.; Liu, Q.-Z.; Luo, S.-W.; Yuan, W.-C. Chem.;Eur. J.
HOMO-activated 2-amino-1,3-butadienes derived from
enones and chiral amine catalysts are valuable intermedi-
2
013, 19, 7143. (c) He, Y.; Kang, T.-R.; Liu, Q.-Z.; Chen, L.-M.; Tu,
Y.-L.; Chen, T.-B.; Wang, Z.-Q.; Liu, J.; Xie, Y.-M.; Yang, J.-L.; He, L.
Org. Lett. 2013, 15, 4054. (d) Li, J.-L.; Kang, T.-R.; Zhou, S.-Li; Li, R.;
Wu, L.; Chen, Y.-C. Angew. Chem., Int. Ed. 2010, 49, 6418.
5
ates in organic synthesis. Barbas and co-workers first
reported the amine-catalyzed [4 þ 2] cycloaddition of
(
11) For recent reviews on aminocatalysis, see: (a) Bertelsen, S.;
6
nitroalkenes and 2-amino-1,3-butadienes in 2002. After
Jørgensen, K. A. Chem. Commun. 2009, 2178. (b) Mukherjee, S.; Yang,
J. W.; Hoffmann, S.; List, B. Chem. Rev. 2007, 107, 5471. (c) Lelais, G.;
MacMillan, D. W. C. Aldrichimica Acta 2006, 39, 79. (d) Enders, D.;
Grondal, C.; H u€ ttl, M. R. M. Angew. Chem., Int. Ed. 2007, 46, 1570. (e)
Yeboah, E. M. O.; Yeboah, S. O.; Singh, G. S. Tetrahedron 2011, 67,
this event, tremendous chemists have dedicated to amine
catalyzed cycloaddition reaction of enones and various
7
electron-deficient dienophiles. It is known that imines are
1
725. (f) Melchiorre, P. Angew. Chem., Int. Ed. 2012, 51, 9748.
12) (a) Bella, M.; Jøgensen, K. A. J. Am. Chem. Soc. 2004, 126, 5672.
(b) Chen, Z.-H.; Furutachi, M.; Kato, Y.; Matsunaga, S.; Shibasaki, M.
reactive in the hetero DielsꢀAlder reactions of siloxybu-
(
tadiene derivatives as dienes, such as Danishefsky’s diene
Angew. Chem., Int. Ed. 2009, 48, 2218.
[Scheme 1, (1a)] in the presence of a Lewis or Brønsted
8
acid. However, acyclic enones or ynones are seldeom
(
13) For the previous work on amino enyne catalysis, see: (a)
Ramachary, D. B.; Venkaiah, C.; Madhavachary, R. Org. Lett. 2013,
5, 3042. (b) Ramachary, D. B.; Venkaiah, Ch.; Krishna, P. M. Chem.
1
Commun. 2012, 48, 2252. (c) Silva, F.; Sawicki, M.; Gouverneur, V. Org.
Lett. 2006, 8, 5417.
(
5) (a) Li, J.-L.; Liu, T.-Y.; Chen, Y.-C. Acc. Chem. Res. 2012, 45,
491. (b) Feng, X.; Zhou, Z.; Zhou, R.; Zhou, Q.-Q.; Dong, L.; Chen,
Y.-C. J. Am. Chem. Soc. 2012, 134, 19942.
6) Thayumanavan, R.; Dhevalapally, B.; Sakthivel, K.; Tanaka, F.;
Barbas, C. F., III. Tetrahedron Lett. 2002, 43, 3817.
7) For selected examples, see: (a) Bencivenni, G.; Wu, L.-Y.; Mazzanti,
1
(14) For reviews of allenes in organic synthesis, see: (a) Modern
Allene Chemistry; Krause, N., Hashmi, A. S. K., Eds.; Wiley-VCH:
Weinheim, 2004. (b) Ma, S. Chem. Rev. 2005, 105, 2829. (c) Kim, H.;
Willams, L. J. Curr. Opin. Drug Discovery Dev. 2008, 11, 870.
(15) For examples of synthesis of chiral allenes, see: (a) Hoffmann-
R o€ der, A.; Krause, N. Angew. Chem., Int. Ed. 2002, 41, 2933. For
examples, see: (b) de Graaf, W.; Boersma, J.; van Koten, G.; Elsevier,
C. J. J. Organomet. Chem. 1989, 378, 115. (c) Ogasawara, M.; Ikeda, H.;
Nagano, T.; Hayashi, T. J. Am. Chem. Soc. 2001, 123, 2089. (d) Han,
J. W.; Tokunaga, N.; Hayashi, T. J. Am. Chem. Soc. 2001, 123, 12915. (e)
Hayashi, T.; Tokunaga, N.; Inoue, K. Org. Lett. 2004, 6, 305. (f) Li,
C.-Y.; Wang, X.-B.; Sun, X.-L.; Tang, Y.; Zheng, J.-C.; Xu, Z.-H.;
Zhou, Y.-G.; Dai, L.-X. J. Am. Chem. Soc. 2007, 129, 1494. (g) Trost,
B. M.; Xie, J. J. Am. Chem. Soc. 2008, 130, 6231. (h) Liu, H.; Leow, D.;
Huang, G.-W.; Tan, C.-H. J. Am. Chem. Soc. 2009, 131, 7212. (i) Zhang,
X.; Zhang, S.; Wang, W. Angew. Chem., Int. Ed. 2010, 49, 1481. (j) Liu,
C.; Zhang, X.; Wang, R.; Wang, W. Org. Lett. 2010, 12, 4948. (k)
(
(
A.; Giannichi, B.; Pesciaioli, F.; Song, M.-P.; Bartoli, G.; Melchiorre, P.
Angew. Chem., Int. Ed. 2009, 48, 7200. (b) Wu, L.-Y.; Bencivenni, G.;
Mancinelli, M.; Mazzanti, A.; Bartoli, G.; Melchiorre, P. Angew. Chem.,
Int. Ed. 2009, 48, 7196. (c) Ramachary, D. B.; Chowdari, N.; Chowdari, S.;
Barbas, C. F., III. Angew. Chem., Int. Ed. 2003, 42, 4233. (d) Yamamoto,
Y.; Momiyama, N.; Yamamoto, H. J. Am. Chem. Soc. 2004, 126, 5962. (e)
Sund ꢀe n, H.; Rios, R.; Xu, Y.; Eriksson, L.; C oꢀ rdova, A. Adv. Synth. Catal.
2
007, 349, 2549. (f) Cui, H.-L.; Tanaka, F. Chem.;Eur. J. 2013, 19, 6213.
8) For reviews on the reaction of imines and electron-rich dienes or
enones, see: (a) Girling, P. R.; Kiyoi, T.; Whiting, A. Org. Biomol. Chem.
011, 9, 3105. (b) Masson, G.; Lalli, C.; Benhoud, M.; Dagousset, G.
(
2
Chem. Soc. Rev. 2013, 42, 902. (c) Taggi, A.; Hafez, A.; Wack, H.;
Young, B.; Ferraris, D.; Lectka, T. J. Am. Chem. Soc. 2002, 124, 6626.
Alem ꢀa n, J.; N uꢀ nꢁ ez, A.; Marzo, L.; Marcos, V.; Alvarado, C.; Garcı
´
a
(
d) France, S.; Shah, M. H.; Weatherwax, A.; Wack, H.; Roth, J. P.;
Lectka, T. J. Am. Chem. Soc. 2005, 127, 1206.
9) (a) Itoh, T.; Yokoya, M.; Miyauchi, K.; Nagata, K.; Ohsawa, A.
Ruano, J. L. Chem.;Eur. J. 2010, 16, 9453. (l) Zhang, X.; Zhang, S.;
Wang, W. Angew. Chem., Int. Ed. 2010, 49, 1481.
(16) (a) Hachiya, I.; Ogura, K.; Shimizu, M. Org. Lett. 2002, 4, 2755.
(b) Shimizu, M.; Nishi, T.; Yamamoto, A. Synlett 2003, 1469. For the
use of silyloxyallenes in enantioselective synthesis, see: (c) Reynolds,
T. E.; Scheidt, K. A. Angew. Chem., Int. Ed. 2007, 46, 7806 and references
cited therein.
(
Org. Lett. 2006, 8, 1533. (b) Nagata, K.; Ishikawa, H.; Tanaka, A.;
Miyazaki, M.; Kanemitsu, T.; Itoh, T. Heterocycles 2010, 81, 1791. (c)
Lalonde, M. P.; McGowan, M. A.; Rajapaksa, N. S.; Jacobsen, E. N.
J. Am. Chem. Soc. 2013, 135, 1891.
Org. Lett., Vol. 15, No. 23, 2013
6091