Organic Syntheses Procedure

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Org. Synth. 1971, 51, 53

DOI: 10.15227/orgsyn.051.0053

AZIRIDINES FROM β-IODOCARBAMATES: 1,2,3,4-TETRAHYDRONAPHTHALENE(1,2)IMINE

[1H-Naphth[1,2-b]azirine, 1a,2,3,7b-tetrahydro-]

Submitted by C. H. Heathcock¹ and A. Hassner².

Checked by William G. Kenyon and Richard E. Benson.

1. Procedure

A 500-ml., round-bottomed flask equipped with a reflux condenser is charged with a solution of 25 g. of potassium hydroxide in 250 ml. of 95% ethanol, to which is added 16.6 g. (0.0498 mole) of methyl (trans-2-iodo-1-tetralin)carbamate (Note 1). The resulting mixture is heated under reflux on a stream bath for 2 hours, cooled, and added to 500 ml. of water. The clear, yellow solution is shaken three times with 100-ml. portions of diethyl ether. The ether layers are combined, washed three times with 125-ml. portions of water and once with 125 ml. of a saturated sodium chloride, dried over 5 g. of anhydrous potassium carbonate, and filtered. The ether is removed by distillation on a steam bath, giving the crude imine as a yellow-brown oil (Note 2). The oil is transferred to a small flask, the container is rinsed with ether, and the rinse is added to the distillation flask. The product is collected by distillation through a small Vigreux column with warm water circulating through the condenser to prevent crystallization of the product. The fraction boiling at 80–82° (0.15–0.25 mm.) is collected as a solid that forms in the receiver, yielding 4.9–5.1 g. (68–70%) of the imine, m.p. 54–56° (Note 2); the IR spectrum has a band at 3205 cm.⁻¹ (NH) (Note 3).

2. Notes

1. The methylcarbamate may be prepared by the procedure in Org. Synth., Coll. Vol. 6, 795 (1988).

2. The submitters state that product, m.p. 49–51°, can be obtained by direct crystallization of the oil. The oil from a run conducted on a scale twice that described above is cooled to −15° and 30 ml. of pentane is added. Upon scratching the flask, the product crystallizes, is collected by filtration, and washed with a little cold pentane, yielding 9–10 g. (62–69%), m.p. 49–51°.

3. The ¹H NMR spectrum (CCl₄) shows a broad singlet centered at δ 0.7 (1H) and complex multiplets at 1.1–3.05 (6H) and 6.76–7.30 (4H).

3. Discussion

The procedure reported here, that of Hassner and Heathcock,³ is more convenient than the Wenker synthesis of aziridines⁴ and appears to be more general.⁵ It represents a simple route from olefins to aziridines (via β-iodocarbamates).³^,⁵^,⁶ Aziridines are also useful as intermediates in the synthesis of amino alcohols and heterocyclic systems.⁵^,⁷^,⁸^,⁹

This preparation is referenced from:

Org. Syn. Coll. Vol. 6, 795

References and Notes

Department of Chemistry, University of California, Berkeley, California 94720.
Present address: Department of Chemistry, State University of New York, Binghamton, New York 13901.
A. Hassner and C. Heathcock, Tetrahedron, 20, 1037 (1964).
O. E. Paris and P. E. Fanta, J. Am. Chem. Soc., 74, 3007 (1952).
A. Hassner and C. Heathcock, J. Org. Chem., 30, 1748 (1965).
G. Drefahl and K. Ponsold, Chem. Ber., 93, 519 (1960).
H. W. Heine, Angew. Chem., 74, 772 (1962) [Angew. Chem. Int. Ed. Engl., 1, 528 (1962)].
A. Hassner, M. E. Lorber, and C. Heathcock, J. Org. Chem., 32, 540 (1967).
L. A. Paquette and D. E. Kuhla, Tetrahedron Lett., 4517 (1967).

Appendix
Chemical Abstracts Nomenclature (Collective Index Number);
(Registry Number)

β-IODOCARBAMATES

ethanol (64-17-5)

potassium carbonate (584-08-7)

ether,
diethyl ether (60-29-7)

sodium chloride (7647-14-5)

potassium hydroxide (1310-58-3)

Pentane (109-66-0)

methylcarbamate

1,2,3,4-Tetrahydronaphthalene(1,2)imine,
1H-Naphth[1,2-b]azirine, 1a,2,3,7b-tetrahydro- (1196-87-8)

Methyl (trans-2-iodo-1-tetralin)carbamate (1210-13-5)

Notes

References/EndNotes

Article Compounds

Authors