Talk:Todd:Catalytic, Asymmetric Pictet-Spengler Reaction
Use this page for discussion. Preface questions/comments with initials.
MHT - Jan19 - the page is quite long. We could consider splitting into sections if anyone is having a browser problem, but otherwise we keep as-is. Much more convenient having everything on one page.
Things that need doing (updated 20/01/12):
Check suitability of "items arising" from the 2004 Terada and Akiyama papers
Items arising from Akiyama and Terada papers: More on early work:
Akiyama (2004) says these earlier reports "claim" the use of chiral B acids:
- B. L. Hodous, G. C. Fu, J. Am. Chem. Soc. 2002, 124, 10006 - Reaction of pyrroles with ketenes catalysed by a PPY planar-chiral 4-(pyrrolidino)pyridine (PPY), which is Fe π-bonded complex (KAB: not sure where "Possible Intervention" comes in).
- C. Palomo, M. Oiarbide, J. M. Garcia, A. Gonzalez, A. Lecumberri, A. Linden, J. Am. Chem. Soc. 2002, 124, 10288
- N. T. McDougal, S. E. Schaus, J. Am. Chem. Soc. 2003, 125, 12094
- Y. Huang, A. K. Unni, A. N. Thadani, V. H. Rawal, Nature 2003, 424, 146.
Akiyama (2004) also mentions these "metal salt" versions:
- J. Inanaga, Y. Sugimoto, T. Hanamoto, New J. Chem. 1995, 19, 707
- H. Furuno, T. Hanamoto, Y. Sugimoto, J. Inanaga, Org. Lett. 2000, 2, 49
Previous Bronsted acid example from Terada
- Schreiner, P. R. Chem. Soc. ReV. 2003, 32, 289.
- Huang, Y.; Unni, A. K.; Thadani, A. N.; Rawal, V. H. Nature 2003, 424, 146.
- McDougal, N. T.; Schaus, S. E. J. Am. Chem. Soc. 2003,125, 12094.
Some other chiral charged Brønsted acid catalysts were reported, see:
- Nugent, B. M.; Yoder, R. A.; Johnston, J. N. J. Am. Chem. Soc. 2004,126, 3418.
Jacobsen Strecker and Mannich history, from Terada
- Sigman, M. S.; Jacobsen, E. N. J. Am. Chem. Soc. 1998, 120, 4901.
- Vachal, P.; Jacobsen, E. N. Org. Lett. 2000, 2, 867.
- Sigman, M. S.; Vachal, P.; Jacobsen, E. N. Angew. Chem., Int. Ed. 2000, 39, 1279.
- Su, J. T.; Vachal, P.; Jacobsen, E. N. AdV. Synth. Catal. 2001, 343, 197.
- Vachal, P.; Jacobsen, E. N. J. Am. Chem. Soc. 2002, 124, 10013.
- Wenzel, A. G.; Lalonde, M. P.; Jacobsen, E. N. Synlett 2003, 1919.
- Wenzel, A. G.; Jacobsen, E. N. J. Am. Chem. Soc. 2002, 124, 12964.
See also:
- Okino, T.; Hoashi, Y.; Takemoto, Y. J. Am. Chem. Soc. 2003, 125, 12672.
- Okino, T.; Nakamura, S.; Furukawa, T.; Takemoto,Y. Org. Lett. 2004, 6, 625.
Copper complex example from Terada:
- Marigo, M.; Kjærsgaard, A.; Juhl, K.; Gathergood, N.; Jørgensen, K. A. Chem.- Eur. J. 2003, 9, 2359.
(end of items arising)
Papers to Summarise/Check for Suitability
Enantioselective/Lewis Acids:
- Hino, T.; Nakagawa, M. Heterocycles 1998, 49, 499-531.
- Leighton Angew 2009
Enantioselective/Bronsted Acids:
The strengths of these chiral phosphoric acids is governed by: Akiyama Chem Rev 2007 Terada ChemComm 2008 Reviews: a) S.J. Connon, Angew. Chem. Int. Ed. 2006, 45, 3909–3912 b) T. Akiyama, J. Itoh, K. Fuchibe, Adv. Synth. Catal. 2006, 348, 999 – 1010 c) M. S. Taylor, E. N. Jacobsen, Angew. Chem. Int. Ed. 2006, 45, 1520–1543 d) Connon, S. J. Org. Biomol. Chem. 2007, 5, 3407–3417 e) Terada Synthesis 2010, 1929-1982 f) List, Top. Curr. Chem. 2010, 291, 395-456 g) Rueping Angewandte 2011, 50, 6706-6720
Enantioselective/Organocatalysts: Jacobsen 2007 JACS, 129, 13404
Diastereoselective (note: must be catalytic):
- Czarnocki, Z.; MacLean, D. B.; Szarek, W. A. Can. J. Chem. 1986, 64, 2205-2210.
- Czarnocki, Z.; Suh, D.; MacLean, D. B.; Hultin, P. G.; Szarek, W. A. Can. J. Chem. 1992, 70, 1555-1561.
- Czarnocki, Z.; Mieckzkowsi, J. B.; Kiegiel, J.; Arazn ́y, Z. Tetrahyedron: Asymmetry 1995, 6, 2899-2902.
- Tsuji, R.; Nakagawa, M.; Nishida, A. Tetrahedron: Asymmetry 2003, 14, 177- 180.
Archived/inactive discussions:
1. KAB attempt to understand 2000 Koomen OrgLett (archived since this paper no longer included)
The figure for Table 1 gives diasteromeric ratios. Where are the diastereomers? I only the possibility for enantiomers in the product. Where's the other stereogenic centre?
They also mentioned "hydrolysis of the starting material" numerous times. I'm assuming they mean hydrolysis of the N-S bond (there doesn't seem any other reasonable place for hydrolysis of the SM to occur), but I just wanted to check.