2-Chloro-1,3-dimethylimidazolinium Chloride. 3. Roles
J . Org. Chem., Vol. 64, No. 16, 1999 5835
Sch em e 4
imine was obtained as a sole product when the oximes
derived from 4-(4-hydroxy- or 4-methoxyphenyl)-2-bu-
tanones were used (Scheme 4). The yield was high in each
case. Recently Narasaka and co-workers15 reported the
same intramolecular cyclization of oximes affording aza-
spirodienones by treatment with a mixture of tetrabu-
tylammonium perrhenate and trifluoromethanesulfonic
acid. In this case the conditions (in 1,2-dichloroethane
at reflux for 1 h) used were more drastic than ours (in
dichloromethane at room temperature for 20 min). How-
ever, benzoin oxime yielded a cleavage product through
an alternative path (Scheme 5).
Sch em e 5
Con clu sion s
As mentioned above, DMC (1) can be used in chlorina-
tion, oxidation, reduction, and rearrangement reactions.
These reactions are caused by the strong electrophilicity
of 1, as well its activity as a dehydrating reagent. In
summary, DMC is a more versatile reagent than DCC
because of not only its ability to act as an electrophile
but also simple product isolation.
Exp er im en ta l Section
General comments and a basic procedure for the reaction
using 1 were given in the preceding paper.1a
(S)-N-Car boben zoxy-1-ben zyl-2-ch lor oeth ylam in e (r u n
5 in Ta ble 1). Colorless prisms (from hexane-ethyl acetate);
mp 72-73 °C. Anal. Calcd for C17H18ClNO2: C, 67.21; H, 5.97;
N, 4.61. Found: C, 67.26; H, 6.02; N, 4.54. FABMS m/z: 304
alcohols or a thiol in place of amines afforded carbamates
(runs 1-6 in Table 712) or a thiocarbamate (run 7 in Table
712).
1
(MH+), 306 (MH+ + 2); H NMR (300 MHz, CDCl3): δ 2.86-
Beckmann-like rearrangements13 were also observed
when oximes were treated with 1 (Table 814). Carboxa-
mides were obtained in good yields. Interestingly a spiro-
3.00 (m, 2H), 3.50 (dd, J ) 11.3, 3.1 Hz, 1H), 3.64 (dd, J )
11.3, 3.8 Hz, 1H), 4.20 (br s, 1H), 5.05 (m, 1H), 5.10 (s, 2H),
7.22-7.39 (m, 10H); 13C NMR (75 MHz, CDCl3): δ 37.7, 46.7,
52.6, 66.9, 126.9, 128.1, 128.2, 128.6, 128.7, 129.3, 136.2, 136.8,
155.5; IR (KBr): 1685 cm-1 (CdO); [R]25D -17.8 (c 1.00, CHCl3).
(12) References to the products in Table 7 are as follows: (a) run 1;
Hofmann, A. W. Ann. 1850, 74, 1. (b) run 2; Meiser, W. Chem. Ber.
1899, 32, 2049. (c) run 3; Oeda, H. Bull. Chem. Soc. J pn. 1935, 10,
531. (d) run 4; Van Zyl, G.; Langenberg, R. J .; Tan, H. H.; Schut, R. N.
J . Am. Chem. Soc. 1956, 78, 1955. (e) run 5; Huang, X.; Keillor, J . W.
Tetrahedron Lett. 1997, 38, 313 (f) run 6; Kienzle, F. Tetrahedron Lett.
1972, 1771. (g) run 7; Bourne, N.; Williams, A.; Douglas, K. T.;
Penkava, T. R. J . Chem. Soc., Perkin Trans. 2 1984, 1827.
(13) Heldt, W. Z. Org. React. 1960, 11, 1. Gawley, R. E. Org. React.
1988, 35, 1.
Su p p or tin g In for m a tion Ava ila ble: Selected spectro-
scopic data for compounds described in our patents. This
material is available free of charge via the Internet at
http://pubs.acs.org.
J O990211Q
(14) Reference to the product in run 4 in Table 8 is as folows:
Dickerman, S. C.; Besozzi, A. J . J . Org. Chem. 1954, 19, 1855.
(15) Kusama, H.; Uchiyama, K.; Yamashita, Y.; Narasaka, K. Chem.
Lett. 1995, 715.