Author Topic: Ring Opening Reactions of N-Tosyl Aziridines  (Read 1288 times)

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lutesium

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Ring Opening Reactions of N-Tosyl Aziridines
« on: October 06, 2004, 04:02:00 PM »
While methyl- and benzylamines openedN-tosyl aziridines 1
very effciently in acetonitrile with complete regio- and stereoselectivity to give the corresponding diamines 2 and 3, respectively, in excellent yields, similar openings with water could only be achieved in the presence of a catalytic amount of cerium(IV)ammonium nitrate under very mild conditions furnishing the amino alcohols.

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Rhodium

  • Guest
Explain yourself
« Reply #1 on: October 06, 2004, 07:11:00 PM »
So? I fail to see your point with posting this article. Also make sure that you always post journal/page/title with any PDF file so that it can be found using TFSE later on.


lutesium

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This one is an example about the usage of...
« Reply #2 on: October 06, 2004, 10:04:00 PM »
This one is an example about the usage of cerium ammonium nitrate for the creation of amino alcohols from aziridines which can be prepared from epoxides that might be synthesised via the oxidation of styrenes.

The first table shows the products from an amine catalyst in CH3CN

I think you should look at the second table which shows useful info. CAN produces amino alcohols from the corresponding aziridines in acetonitrile.

I think you got the point.

Rhodium

  • Guest
And how was that done?
« Reply #3 on: October 07, 2004, 12:12:00 AM »
Did you bother to read how they prepared the aziridines?


The starting aziridines 1a–f were prepared from the corresponding epoxides in four steps: (a) ring opening of the epoxides with NaN3 in MeOH:H2O (8:1) in presence of NH4Cl22 (b) reduction of the resulting azides to amines using Ph3P in dry THF; (c) protection of the amines as tosylates using TsCl, Et3N in CH2Cl2 and (d) treatment of N-tosyl amino alcohols with diethyl azodicarboxylate and Ph3P in dry THF.



After step (b) the amino alcohol is already synthesized. Thus your suggested procedure is a method for turning amino alcohols into tosyl-aziridines and then back into amino alcohols, but this time with an N-tosyl group attached to it. Futile, I'd say.




lutesium

  • Guest
You are right rhodium. But:
« Reply #4 on: October 07, 2004, 02:31:00 AM »
I know they do it like that and turn back in the synthetic scheme only to prove that CAN catalyzed aziridine - aminoalcohol conversion is possible. But there are many ways of creating an aziridine. Then the method will be useful to open the ring. Not futile i think.
Here's an example of a aziridine synth. method


 A Convenient Method for the Synthesis of 2-Arylaziridines from Styrene Derivatives via 2-Arylethenyl(diphenyl)sulfonium Salts
 
 
Styrene derivatives reacted with diphenyl(trifluoromethanesulfonyloxy)sulfonium trifluoromethanesulfonate (1) at low temperature to afford 2-arylethenyl(diphenyl)sulfonium triflates (2). Treatment of 2 with primary amines gave the corresponding 2-arylaziridines in high yields. One-pot synthesis of various aziridines was also successfully carried out without isolation of the intermediate 2
 



  References
1) J. A. Deyrup, in “Small Ring Heterocycles,” ed. by A. Hassner, John Wiley and Sons, New York (1983), Part 1, p 1.
 
 
2) D. Tanner, Angew. Chem., Int. Ed. Engl., 33, 599 (1994).
 
 
3) a) O. C. Dermer and G. E. Ham, “Ethylenimine and Other Aziridines,” Academic Press, New York (1969), p 403.
 
 
 b) Y. Kishi, J. Nat. Prod., 42, 549 (1979).
 
 
4) a) N. H. Cromwell, G. V. Hudson, R. A. Wankel, and P. J. Vanderhorst, J. Am. Chem. Soc., 75, 5384 (1963).
 
 
 b) D. L. Nagel, P. B. Woller, and N. H. Cromwell, J. Org. Chem., 36, 3911 (1971).
 
 
 c) G. Cardillo, L. Gentilucci, C. Tomasini, and M. P. V. Castejon-Bordas, Tetrahedron: Asymmetry, 7, 755 (1996).
 
 
5) G. Aumaitre, J. Chanet-Ray, J. Durand, and R. Vessière, Synthesis, 1983, 816.
 
 
6) a) C. R. Johnson and J. P. Lockard, Tetrahedron Lett., 12, 4589 (1971).
 
 
 b) C. R. Johnson, J. P. Lockard, and E. R. Kennedy, J. Org. Chem., 45, 264 (1980).
 
 
7) a) V. G. Nenajdenko, P. V. Vertelezkij, I. D. Gridnev, N. E. Shevchenko, and E. S. Balenkova, Tetrahedron, 53, 8173 (1997).
 
 
 b) K. Hartke, D. Teuber, and H.-D. Gerber, Tetrahedron, 44, 3261 (1988).
 
 
 c) For a review, see: A. J. Mancuso and D. Swern, Synthesis, 1981, 165.
 
 
8) Note without reference.
 
 
9) See: P. E. Fanta, in “Heterocyclic Compounds with Three- and Four-Membered Rings,” ed. by A. Weissberger, John Wiley and Sons, New York (1964), Part 1, p 527.
 
 
10) a) J. Gosselck, L. Béress, and H. Schenk, Angew. Chem., 78, 606 (1966).
 
 
 b) J. Gosselck, H. Ahlbrecht, F. Dost, H. Schenk, and G. Schmidt, Tetrahedron Lett., 9, 995 (1968).
 
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