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PAPER
References
Enamines 1a–g11 and succinimide12 were prepared by methods pub-
lished in the literature.
(1) a) Vilsmaier, E.; Stamm, T.; Michels, G. Synthesis 1988, 858.
b) Wasserman, H. H.; Baird, M. S. Tetrahedron Lett. 1971,
3721.
Cyclopropane N,O-Acetals 2; General Procedure
(2) a) Vilsmaier, E.; Goerz, T. Synthesis 1998, 739.
b) Vilsmaier, E.; Stamm, T.; Dauth, W.; Tezlaff, C.; Barth,
S. Bull. Soc. Chim. Belg. 1992, 101, 37.
To a stirred solution of enamine 1 (30 mmol) in MeOH (60 mL)
containing NaOMe (60 mmol) was added iodine (30 mmol) portion-
wise at r.t. over 2 h. The stirring was continued for 30 min, and the
mixture was evaporated in vacuo. H2O (20 mL) was added to the
residue, and the organic layer was extracted with Et2O (3 x 20 mL).
The combined Et2O extracts were washed with brine (20 mL), dried
(Na2SO4), and distilled in vacuo. The products 2k and 2m were iso-
lated as a mixture of cis and trans isomers by column chromatogra-
phy on aluminium oxide using Et2O/hexane (1:1) as the eluent.
c) Vilsmaier, E.; Tröger, W.; Haag G. Chem. Ber. 1981, 114,
67.
d) Vilsmaier, E.; Klein, C. M.; Dausmann. D.; Maas, G. Chem.
Ber. 1982, 115, 1209.
e) Vilsmaier, E.; Tröger, W. Synthesis 1980, 463.
f) Vilsmaier, E.; Scheiber, L. Synthesis 1980, 465.
(3) Szmuszkovicz, J.; Duchamp, D. J.; Cerda, E.; Chidester, C.
G. Tetrahedron Lett. 1969, 1309.
(4) Chiba, T.; Iida, T.; Okimoto, M. to be published
(5) Vilsmaier, E.; Tröger, W. Angew. Chem. 1979, 91, 860;
Angew. Chem., Int. Ed. Engl. 1979, 18, 615.
Vilsmaier, E.; Klein, C. M. Angew. Chem. 1979, 91, 861;
Angew. Chem., Int. Ed. Engl. 1979, 18, 616.
(6) Vilsmaier, E.; Klein, C. M.; Tröger, W. Chem. Ber. 1982, 115,
2795.
(7) Vilsmaier, E.; Fath, J.; Maas, G. Synthesis 1991, 1142.
Blazejewski, J. C.; Cantacuzene, D.; Wakselman, C.
Tetrahedron 1973, 29, 4233.
Cyclopropane Aminonitrile 3; General Procedure
To a stirred solution of enamine 1 (20 mmol) in MeOH (40 mL)
containing NaOMe (20 mmol) and NaCN (40 mmol) was added io-
dine (20 mmol) portionwise at 30 °C over 1 h. For 1h, iodine (30
mmol), and for 1l, MeOH (80 mL) was used. After workup as de-
scribed above, the combined Et2O extracts were washed with dil.
HCl (10 mL), washed with brine (20 mL), dried (Na2SO4), and dis-
tilled in vacuo. The products 3j and 3l were isolated as a mixture of
the cis and trans isomers by column chromatography on silica gel
using Et2O/hexane (1:1) as the eluent. Separation of the two isomers
was achieved by cooling a solution of the mixture in hexane at
-50°C. The crystallized cis isomer was collected by filtration, and
rinsed with small portions of cold hexane. The trans isomer was ob-
tained from the mother liquid by Kugelrohr distillation.
(8) Ahlbrecht, H.; Raab, W. Synthesis 1980, 320.
(9) Bak, B.; Hillebert, A. Org. Synth. 1963, 4, 207.
(10) Fusco, R.; Rossi, S.; Bianchetti, G. Gazz. Chim. Ital. 1961, 91,
841.
(11) Hünig, S., Lücke, E., Brenninger, W. Org. Synth. 1973, 5, 808.
Blanchard, Jr. E. P. J. Org. Chem. 1963, 28, 1397.
Stork, G.; Brizzolara, A.; Landesman, H.; Szmuszkovicz, J.;
Terrell, R. J. Am. Chem. Soc. 1963, 85, 207.
Kuehne, M. E. J. Am. Chem. Soc. 1959, 81, 5400.
Mannich, C.; Davidsen, H. Chem. Ber. 1936, 59, 2106.
(12) Clarke, H. T.; Behr, L. D. Org. Synth. 1943, 2, 562.
Cyclopropane Succinimide 4; General Procedure
Enamine 1 (10 mmol) was dissolved in a solution of succinimide
(20 mmol) in MeOH (20 mL) containing NaOMe (20 mmol). Iodine
(10 mmol) was then added to the solution at r.t. over 1 h. Stirring
was continued for an additional 1 h, and the mixture was evaporated
in vacuo. The residue was treated with H2O (20 mL), and the solid
was collected by filtration, washed with dil. NaOH (10 mL), washed
with H2O (10 mL), and rinsed with pentane (10 mL). In the case of
4k and 4m, each isomer was separated by fractional recrystalliza-
tion from MeCN.
Article Identifier:
1437-210X,E;1999,0,06,1022,1026,ftx,en;F03698SS.pdf
Synthesis 1999, No. 6, 1022–1026 ISSN 0039-7881 © Thieme Stuttgart · New York
Chiba, Toshiro
