Organic Process Research & Development
Page 26 of 27
1
2
3
4
5
6
7
8
(6) Kobayashi, S.; Ishitani, H.; Nagayama, S. Lanthanide Triflate Catalyzed Imino Diels-Alder
Reactions; Convenient Syntheses of Pyridine and Quinoline Derivatives. Synthesis 1995, 1195-
1202.
(7) Bellamy, F. D.; Ou, K. Selective reduction of aromatic nitro compounds with stannous chloride
in non-acidic and non-aqueous medium. Tetrahedron Lett. 1984, 25, 839-842.
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(8) For reviews on the Povarov reaction see (a) Sridharan, V.; Suryavanshi, P.; Menendez, J. C.
Advances in the chemistry of tetrahydroquinolines. Chem. Rev. 2011, 111, 7157-7259; (b)
Muthukrishnan, I.; Sridharan, V.; Menendez, J. C. Progress in the Chemistry of
Tetrahydroquinolines. Chem. Rev. 2019, 119, 5057-5191.
(9) (a) Chen, Z.; Wang, B.; Wang, Z.; Zhu, G.; Sun, J. Complex bioactive alkaloid-type polycycles
through efficient catalytic asymmetric multicomponent aza-Diels-Alder reaction of indoles with
oxetane as directing group. Angew. Chem., Int. Ed. 2013, 52, 2027-2031; (b) Yu, X.-L.; Kuang,
L.; Chen, S.; Zhu, X.-L.; Li, Z. L.; Tan, B.; Liu, X.-Y. Counteranion-Controlled Unprecedented
Diastereo- and Enantioselective Tandem Formal Povarov Reaction for Construction of Bioactive
Octahydro-Dipyrroloquinolines. ACS Catal. 2016, 6, 6182−6190; (c) Min, C.; Seidel, D.
Stereochemically Rich Polycyclic Amines from the Kinetic Resolution of Indolines through
Intramolecular Povarov Reactions. Chem. Eur. J. 2016, 22, 10817−10820; (d) Jarrige, L.;
Blanchard, F.; Masson, G. Enantioselective Organocatalytic Intramolecular Aza-Diels-Alder
Reaction. Angew. Chem. Int. Ed. 2017, 56, 10573-10576.
(10) (a) Min, C.; Mittal, N.; Sun, D. X.; Seidel, D. Conjugate-base-stabilized Brønsted acids as
asymmetric catalysts: enantioselective Povarov reactions with secondary aromatic amines. Angew.
Chem., Int. Ed. 2013, 52, 14084-14088; (b) Min, C.; Lin, C.-T.; Seidel, D. Catalytic
Enantioselective Intramolecular Aza-Diels-Alder reactions. Angew. Chem., Int. Ed. 2015, 54,
6608-6612; (c) Xu, H.; Zhang, H.; Jacobsen, E. N. Chiral sulfinamidourea/Strong Brønsted Acid
co-catalyzed enantioselective Povarov reaction to access tetrahydroquinolines. Nat. Protoc. 2014,
9, 1860-1866.
(11) Yu, Y.; Jiang, H.-J.; Zhou, Y.; Luo, S.-W.; Gong, L.-Z. Sodium Salts of Anionic Chiral
Cobalt(III) Complexes as Catalysts of the Enantioselective Povarov Reaction. Angew. Chem., Int.
Ed. 2015, 54, 11209-11213.
(12) (a) Palacios, F.; Alonso, C.; Arrieta, A.; Cossío, F. P.; Ezpeleta, J. M.; Fuertes, M.; Rubiales,
G. Lewis Acid Activated Aza‐Diels–Alder Reaction of N‐(3‐Pyridyl)aldimines: An Experimental
and Computational Study. Eur. J. Org. Chem. 2010, 2091-2099; (b) Pérez-Ruiz, R.; Domingo, L.
R.; Jiménez, C.; Miranda, M. A. Experimental and Theoretical Studies on the Radical-Cation-
Mediated Imino-Diels–Alder Reaction. Org. Lett. 2011, 13, 5116-5119; (c) Domingo, L. R.;
Aurell, M. J.; Sáez, J. A.; Mekelleche, S. M. Understanding the mechanism of the Povarov
reaction. A DFT study. RSC Adv. 2014, 4, 25268-25278; (d) Ríos-Gutiérrez, M.; Layeb, H.;
Domingo, L. R. A DFT study of the mechanism of Brønsted acid catalysed Povarov reactions.
Tetrahedron 2015, 71, 9339-9345; (e) Domingo, L. R.; Ríos-Gutiérrez, M.; Emamian, S.
Understanding the stereoselectivity in Brønsted acid catalysed Povarov reactions generating
cis/trans CF3-substituted tetrahydroquinolines: a DFT study. RSC Adv. 2016, 6, 17064-17073; (f)
Mahi, M. A.; Mekelleche, S. M.; Benchouk, W.; Aurell, M. J.; Domingo, L. R. Theoretical study
of the regio- and stereoselectivity of the intramolecular Povarov reactions yielding 5H-
chromeno[2,3-c] acridine derivatives. RSC Adv. 2016, 6, 15759-15769; (g) For a review dealing
predominantly with mechanistic aspects of the Povarov reaction, see: Bello, D.; Ramón, R.;
ACS Paragon Plus Environment
26