Rearrangement of 5-substituted 5-aminopentadienals

Angewandte Chemie - International Edition

Volumn 37, Issue 15, 1998, Pages 2138-2140

  Fischer, Fabian ^a   Berger, Daniel ^a   Neuenschwander, Markus ^a  

^a UNIVERSITY OF BERN   (Switzerland)

Author keywords

Aminopentadienals; Donor acceptor systems; Enynes; Pyrylium salts; Rearrangements

Indexed keywords

EID: 0032541263     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/(SICI)1521-3773(19980817)37:15<2138::AID-ANIE2138>3.0.CO;2-5     Document Type: Article

References (32)

1. Important syntheses: a) K. Hafner, M. Neuenschwander, Angew. Chem. 1968, 80, 443-444; Angew. Chem. Int. Ed. Engl. 1968, 7, 459-460; b) M. E. Kuehne, P. J. Sheeran, J. Org. Chem. 1968, 33, 4406-4413; c) G. Himbert, M. Regitz, Synthesis 1972, 571-573; d) G. Himbert, Angew. Chem. 1979, 91, 432-433; Angew. Chem. Int. Ed. Engl. 1979, 18, 405; e) T. Sasaki, A. Kojima, J. Chem. Soc. C 1970, 476-480.
2. Important syntheses: a) K. Hafner, M. Neuenschwander, Angew. Chem. 1968, 80, 443-444; Angew. Chem. Int. Ed. Engl. 1968, 7, 459-460; b) M. E. Kuehne, P. J. Sheeran, J. Org. Chem. 1968, 33, 4406-4413; c) G. Himbert, M. Regitz, Synthesis 1972, 571-573; d) G. Himbert, Angew. Chem. 1979, 91, 432-433; Angew. Chem. Int. Ed. Engl. 1979, 18, 405; e) T. Sasaki, A. Kojima, J. Chem. Soc. C 1970, 476-480.
3. Important syntheses: a) K. Hafner, M. Neuenschwander, Angew. Chem. 1968, 80, 443-444; Angew. Chem. Int. Ed. Engl. 1968, 7, 459-460; b) M. E. Kuehne, P. J. Sheeran, J. Org. Chem. 1968, 33, 4406-4413; c) G. Himbert, M. Regitz, Synthesis 1972, 571-573; d) G. Himbert, Angew. Chem. 1979, 91, 432-433; Angew. Chem. Int. Ed. Engl. 1979, 18, 405; e) T. Sasaki, A. Kojima, J. Chem. Soc. C 1970, 476-480.
4. Important syntheses: a) K. Hafner, M. Neuenschwander, Angew. Chem. 1968, 80, 443-444; Angew. Chem. Int. Ed. Engl. 1968, 7, 459-460; b) M. E. Kuehne, P. J. Sheeran, J. Org. Chem. 1968, 33, 4406-4413; c) G. Himbert, M. Regitz, Synthesis 1972, 571-573; d) G. Himbert, Angew. Chem. 1979, 91, 432-433; Angew. Chem. Int. Ed. Engl. 1979, 18, 405; e) T. Sasaki, A. Kojima, J. Chem. Soc. C 1970, 476-480.
5. Important syntheses: a) K. Hafner, M. Neuenschwander, Angew. Chem. 1968, 80, 443-444; Angew. Chem. Int. Ed. Engl. 1968, 7, 459-460; b) M. E. Kuehne, P. J. Sheeran, J. Org. Chem. 1968, 33, 4406-4413; c) G. Himbert, M. Regitz, Synthesis 1972, 571-573; d) G. Himbert, Angew. Chem. 1979, 91, 432-433; Angew. Chem. Int. Ed. Engl. 1979, 18, 405; e) T. Sasaki, A. Kojima, J. Chem. Soc. C 1970, 476-480.
6. Important syntheses: a) K. Hafner, M. Neuenschwander, Angew. Chem. 1968, 80, 443-444; Angew. Chem. Int. Ed. Engl. 1968, 7, 459-460; b) M. E. Kuehne, P. J. Sheeran, J. Org. Chem. 1968, 33, 4406-4413; c) G. Himbert, M. Regitz, Synthesis 1972, 571-573; d) G. Himbert, Angew. Chem. 1979, 91, 432-433; Angew. Chem. Int. Ed. Engl. 1979, 18, 405; e) T. Sasaki, A. Kojima, J. Chem. Soc. C 1970, 476-480.
7. Important syntheses: a) K. Hafner, M. Neuenschwander, Angew. Chem. 1968, 80, 443-444; Angew. Chem. Int. Ed. Engl. 1968, 7, 459-460; b) M. E. Kuehne, P. J. Sheeran, J. Org. Chem. 1968, 33, 4406-4413; c) G. Himbert, M. Regitz, Synthesis 1972, 571-573; d) G. Himbert, Angew. Chem. 1979, 91, 432-433; Angew. Chem. Int. Ed. Engl. 1979, 18, 405; e) T. Sasaki, A. Kojima, J. Chem. Soc. C 1970, 476-480.
8. a) M. Neuenschwander, K. Hafner, Angew. Chem. 1968, 80, 444; Angew. Chem. Int. Ed. Engl. 1968, 7, 460;
9. a) M. Neuenschwander, K. Hafner, Angew. Chem. 1968, 80, 444; Angew. Chem. Int. Ed. Engl. 1968, 7, 460;
10. b) H. J. Gais, K. Hafner, M. Neuenschwander, Helv. Chim. Acta 1969, 52, 2641-2657.
11. W. Steglich, G. Höfle, W. König, F. Weygand, Chem. Ber 1968, 101, 308-322.
12. For the synthesis of two highly substituted PP-enynes of type 1, see Y. Sato, Y. Kobayashi, M. Sugiura, H. Shirai, J. Org. Chem. 1978, 43, 199-202; G. Himbert, W. Brunn, Liebigs Ann. Chem. 1985, 2206-2216.
13. For the synthesis of two highly substituted PP-enynes of type 1, see Y. Sato, Y. Kobayashi, M. Sugiura, H. Shirai, J. Org. Chem. 1978, 43, 199-202; G. Himbert, W. Brunn, Liebigs Ann. Chem. 1985, 2206-2216.
14. [1] with ketones: I. G. Ostroumov, E. Yu. Khakunova, A. E. Tsil'ko, I. A. Maretina, A. A. Petrov, Zh. Org. Khim. 1990, 26, 2508-2510; J. Org. Chem. USSR (Engl. Transl.) 1990, 26, 2172-2173.
15. [1] with ketones: I. G. Ostroumov, E. Yu. Khakunova, A. E. Tsil'ko, I. A. Maretina, A. A. Petrov, Zh. Org. Khim. 1990, 26, 2508-2510; J. Org. Chem. USSR (Engl. Transl.) 1990, 26, 2172-2173.
16. 0-catalyzed coupling of trialkylsilyl-or trialkylstannylynamines with 3-iodopropenal or 4-iodobut-3-en-2-one has a much broader scope and makes aldehydes 1a-c and 1g(R = H) available as well: a) A. Bartlome, U. Stämpfli, M. Neuenschwander, Chimia 1991, 45, 346-349; b) D. Berger, Dissertation, Universität Bern, 1995; c) D. Berger, A. Bartlome, M. Neuenschwander, Helv. Chim. Acta 1996, 79, 179-191; d) F. Fischer, Dissertation, Universität Bern, 1998.
17. 0-catalyzed coupling of trialkylsilyl-or trialkylstannylynamines with 3-iodopropenal or 4-iodobut-3-en-2-one has a much broader scope and makes aldehydes 1a-c and 1g(R = H) available as well: a) A. Bartlome, U. Stämpfli, M. Neuenschwander, Chimia 1991, 45, 346-349; b) D. Berger, Dissertation, Universität Bern, 1995; c) D. Berger, A. Bartlome, M. Neuenschwander, Helv. Chim. Acta 1996, 79, 179-191; d) F. Fischer, Dissertation, Universität Bern, 1998.
18. 0-catalyzed coupling of trialkylsilyl-or trialkylstannylynamines with 3-iodopropenal or 4-iodobut-3-en-2-one has a much broader scope and makes aldehydes 1a-c and 1g(R = H) available as well: a) A. Bartlome, U. Stämpfli, M. Neuenschwander, Chimia 1991, 45, 346-349; b) D. Berger, Dissertation, Universität Bern, 1995; c) D. Berger, A. Bartlome, M. Neuenschwander, Helv. Chim. Acta 1996, 79, 179-191; d) F. Fischer, Dissertation, Universität Bern, 1998.
19. 0-catalyzed coupling of trialkylsilyl-or trialkylstannylynamines with 3-iodopropenal or 4-iodobut-3-en-2-one has a much broader scope and makes aldehydes 1a-c and 1g(R = H) available as well: a) A. Bartlome, U. Stämpfli, M. Neuenschwander, Chimia 1991, 45, 346-349; b) D. Berger, Dissertation, Universität Bern, 1995; c) D. Berger, A. Bartlome, M. Neuenschwander, Helv. Chim. Acta 1996, 79, 179-191; d) F. Fischer, Dissertation, Universität Bern, 1998.
20. D. Berger, M. Neuenschwander, Helv. Chim. Acta 1996, 79, 192-202.
21. Mechanistic considerations (for a discussions see ref. [7]) suggest that reactions of acids with 1 should give Z/E mixtures of 2, which could isomerize to the thermodynamically favored Z isomer due to a pronounced π delocalization of 2 (or of protonated 2).
22. 13C NMR, IR, UV, and mass spectra of 1, 2, 4, and 6 as well as discussions of NMR spectra see ref. [6b,d].
23. 4, ca. 40%).
24. Similarly, 2,4-bis(dialkylamino)pyrylium salts are relatively stable towards nucleophiles: R. Spitzner, R. Radeglia, W. Schroth, Tetrahedron Lett. 1985, 26, 3967-3970.
25. A. Niederhauser, G. Bart, M. Neuenschwander, Helv. Chim. Acta 1973, 56, 2427-2449.
26. It should be noted that the energy of 7 is supposed to increase due to the contribution of the "antiaromatic" 4π resonance form 7B, whereas the contribution of the "aromatic" 6π resonance form 4B is thought to lower the energy of 4.
27. The term "pentadienal rearrangement" goes back to Roedig, who showed that perchloropentadienals are subject to a 1,5-O-shift at high temperatures: a) A. Roedig, G. Märkl, S. Schödel, Angew. Chem. 1957, 69, 240; Liebigs. Ann. Chem. 1962, 659, 1-16. b) A. Roedig, G. Märkl, F. Frank, R. Kohlhaupt, M. Schlosser, Chem. Ber. 1967, 100, 2730-2741.
28. The term "pentadienal rearrangement" goes back to Roedig, who showed that perchloropentadienals are subject to a 1,5-O-shift at high temperatures: a) A. Roedig, G. Märkl, S. Schödel, Angew. Chem. 1957, 69, 240; Liebigs. Ann. Chem. 1962, 659, 1-16. b) A. Roedig, G. Märkl, F. Frank, R. Kohlhaupt, M. Schlosser, Chem. Ber. 1967, 100, 2730-2741.
29. The term "pentadienal rearrangement" goes back to Roedig, who showed that perchloropentadienals are subject to a 1,5-O-shift at high temperatures: a) A. Roedig, G. Märkl, S. Schödel, Angew. Chem. 1957, 69, 240; Liebigs. Ann. Chem. 1962, 659, 1-16. b) A. Roedig, G. Märkl, F. Frank, R. Kohlhaupt, M. Schlosser, Chem. Ber. 1967, 100, 2730-2741.
30. 3N is an attractive nucleophilic auxiliary for inducing ring openings of easily available 2-aminopyrylium salts of type 4 (X = Cl, OAc). Experiments in view of generalizing this method are planned.
31. a) W. Flitsch, B. Müter, U. Wolf, Chem. Ber. 1973, 106, 1993-2000;
32. b) W. Flitsch, F. Kappenberg, H. Schmitt, ibid. 1978, 111, 2407-2422.