C. E. Hewton et al. / Tetrahedron Letters 43 (2002) 3199–3201
3201
moderate yields of 65 and 70%, respectively (entries 8
and 10).
Bean, G. P. In The Chemistry of Heterocyclic Compounds,
Pyrroles; Jones, R. A., Ed.; Wiley: New York, 1990; Vol.
48, Part 1, p. 105.
n conclusion, this communication demonstrates the first
reported one-pot synthesis of substituted thiophenes
and pyrroles from 3,5-dihydro-1,2-dioxines. This
methodology involves the participation of a 1,4-dike-
tone, derived from the Kornblum–de la Mare rear-
rangement of the 3,5-dihydro-1,2-dioxine precursor. If
suitable dienes were available for the synthesis of the
4. For recent examples of pyrrole syntheses from 1,4-dike-
tone precursors, see: (a) Surya Prakash Rao, H.; Jothiling-
ham, S. Tetrahedron Lett. 2001, 42, 6595; (b) Braun, R.
U.; Zeitler, K.; Muller, T. J. J. Org. Lett. 2001, 3, 3297.
5
6
7
. (a) Kornblum, N.; de la Mare, H. J. Am. Chem. Soc. 1951,
73, 881; (b) Sengul, M. E.; Ceylan, Z.; Balci, M. Tetra-
hedron 1997, 53, 10401.
3
,5-dihydro-1,2-dioxines, then the synthesis of a large
range of substituted thiophenes and pyrroles would be
possible.
. (a) Clennan, E. L. Tetrahedron 1991, 47, 1343 and refer-
ences cited therein; (b) Avery, T. A.; Taylor, D. K.;
Tiekink, E. R. T. J. Org. Chem. 2000, 65, 5531.
. Spectral data for 3-(4-bromophenyl)-6-phenyl-3,6-dihydro-
1
1
,2-dioxine 2b. Yield 35%; mp 83–84°C; IR (Nujol) 1774,
Acknowledgements
−1 1
681, 1590 cm ; H NMR (CDCl , 300 MHz) l 5.57–5.58
3
(
(
m, 1H), 5.67–5.70 (m, 1H), 6.26–6.37 (m, 2H), 7.32–7.45
13
m, 7H), 7.50–7.54 (m, 2H); C NMR (CDCl , 75 MHz)
3
This work was supported by the Australian Research
Council (ARC).
l 79.2, 80.2, 122.7, 126.6, 127.9, 128.3, 128.5, 128.8, 129.9,
1
+
31.6, 136.9, 137.1; MS m/z (%) 318 (M , 10), 316 (12),
286 (78), 284 (76), 205 (65), 105 (85), 77 (100); HRMS
calcd for C H BrO , 318.0079, found 318.0067.
16
13
2
References
8
. A typical method. A solution of 1,2-dioxine 2b (0.32 g, 1
mmol) and n-butylamine (0.17 g, 2.2 mmol) in dry
methanol (5 ml) was heated to reflux for 16 h under N2.
The reaction was then allowed to cool and the solvent
removed under reduced pressure to yield an orange oil.
The crude mixture was then purified by chromatography
1
. (a) For pyrroles, see: Boger, D. L.; Boyee, C. W.; Labrili,
M. A.; Sehon, C. A.; Jin, Q. J. Am. Chem. Soc. 1999, 121,
5
4 and references cited therein; (b) For thiophenes, see:
Bohlmann, F.; Zdero, C. In The Chemistry of Heterocyclic
Compounds, Thiophene and its Derivatives; Gronowitz, S.,
Ed.; Wiley: New York, 1985; Vol. 44, Part 1, p. 261; (c)
Lehn, J.-M. Supramolecular Chemistry; Concepts and Per-
spectives; VCH: Weinheim, New York, 1995.
. (a) For general methods, see: Gronowitz, S. In The Chem-
istry of Heterocyclic Compounds, Thiophene and its Deriva-
tives; Gronowitz, S. Ed.; Wiley: New York, 1985; Vol. 44,
Part 1, p. 1; (b) Jones, R. A.; Civcir, P. U. Tetrahedron
(
CH Cl ) to yield 2-(4-bromophenyl)-1-butyl-5-phenyl-1H-
2 2
pyrrole 5b (0.23 g, 65%); mp 108–110°C; IR (Nujol) 1598,
−
1 1
1
376, 1202 cm ; H NMR (CDCl , 300 MHz) l 0.58 (t,
3
J=7.2 Hz, 3H), 0.82–0.91 (m, 2H), 1.15–1.24 (m, 2H),
2
4
7
7
1
.07 (t, J=7.5 Hz, 2H), 6.28 (s, 2H), 7.33–7.38 (m, 3H),
.43–7.49 (m, 4H), 7.56–7.58 (m, 2H); C NMR (CDCl3,
5 MHz) l 13.3, 19.3, 32.7, 45.0, 109.5, 109.8, 127.0, 120.8,
13
28.4, 128.9, 130.3, 131.6, 133.1, 133.9, 135.1, 137.1; MS
1
997, 53, 11529; (c) Freeman, F.; Lee, M. Y.; Lu, H.;
+
m/z (%) 355 (M , 98), 353 (100), 312 (99), 310 (97), 299
Wang, X.; Rodriguez, E. J. Org. Chem. 1994, 59, 3695.
. (a) Knorr, L. Chem. Ber. 1884, 17, 1635; (b) Patterson, J.
M. Synthesis 1976, 281 and references cited therein; (c)
(
38), 297 (40), 231 (33), 217 (45), 115 (25); HRMS calcd
3
for C20 20BrN, 353.0780, found 353.0786.
H