1,3-Dihydrobenzo[c]thiophene 2,2-Dioxide

[2471-91-2]  · C8H8O2S  · 1,3-Dihydrobenzo[c]thiophene 2,2-Dioxide  · (MW 168.21)

(a source of o-quinodimethanes1 that are useful diene intermediates in Diels-Alder reactions; a source of benzocyclobutene)

Physical Data: mp 150-151 °C.

Solubility: sol EtOH, CHCl3, C6H6, boiling water; slightly sol Et2O.

Preparative Methods: by oxidation of 1,3-dihydrobenzo[c]thiophene;2 from a,a-Dibromo-o-xylene, rongalite (Sodium Hydroxymethanesulfinate, HOCH2SO2Na.2H2O), and Sulfur Dioxide.3

Purification: recrystallization (H2O; H2O-EtOH; CH2Cl2-petroleum ether; CHCl3-C6H6; C6H6-petroleum ether).

Handling, Storage, and Precautions: unstable to alkali and concentrated H2SO4.

Source of o-Quinodimethane.

Since Cava and Deana proposed and trapped o-quinodimethane as an intermediate in the thermal conversion of 1,3-dihydrobenzo[c]thiophene 2,2-dioxide to benzocyclobutene and 1,2,5,6-dibenzocyclooctadiene,2a its synthetic utility as a diene in Diels-Alder reactions has been investigated extensively. Its isomer, the sultine 1,4-dihydro-2,3-benzoxathiin 3-oxide, also is a precursor of o-quinodimethane, and is especially useful because it decomposes at a lower temperature (80 °C) than does the sulfone.3,4

Substitution of the sulfone via its anion occurs readily,5 thus providing a convenient source for a variety of o-quinodimethane diene components. Both intermolecular (eq 1)6 and intramolecular (eqs 2-5)5 Diels-Alder reactions of o-quinodimethanes have been achieved via thermolysis of the sulfone either in a high boiling solvent or by passing a solution in an inert solvent through a hot (300 °C) quartz tube.5b In one case (eq 6) the cycloaddition occurs across a carbonyl group instead of a vinyl group.5c Steroidal systems have been accessed through intramolecular cyclizations (eq 2)5b,d,e Benzocyclobutenes are obtained from benzo[c]thiophene sulfones,7 and these occasionally are used as sources of o-quinodimethanes. 1-Aryl8 and 1-alkoxy, hydroxy, thioalkyl, and amino9 derivatives of 1,3-dehydrobenzo[c]thiophene 2,2-dioxide are obtained by cyclization reactions and not from the parent compound. Other 1- and 1,3-substituted sulfones are obtained by rhodium(II)-catalyzed cyclization of a-diazo-b-arylmethanesulfonyl esters.10 Chiral 1-alkoxy-1,3-dihydrobenzo[c]thiophene 2,2-dioxides lead to asymmetric induction in the Diels-Alder reaction via the chiral substituent of the o-quinodimethane.9a-c


The nitrated product, 4-nitro-1,3-dihydrobenzo[c]thiophene 2,2-dioxide, gives 3-nitro-1,2-dimethylbenzene on treatment with Raney Nickel.11 Light-catalyzed bromination of the parent sulfone yields 1,3-dibromo-1,3-dihydrobenzo[c]thiophene 2,2-dioxide from which isothianaphthene 2,2-dioxide can be generated and trapped by dienophiles (eq 7).12

Related Reagents.


1. (a) Martin, N.; Seoane, C.; Hanack, M. OPP 1991, 23, 237. (b) Charlton, J. L.; Alauddin, M. M. T 1987, 43, 2873. (c) Rigby, J. H. COS 1991, 5, 622, 638. (d) Oppolzer, W. COS 1991, 5, 385. (e) Oppolzer, W. S 1978, 793. (f) Ciganek, E. OR 1984, 32, 72.
2. (a) Cava, M. P.; Deana, A. A. JACS 1959, 81, 4266. (b) Oliver, J. A.; Ongley, P. A. CI(L) 1965, 1024.
3. Hoey, M. D.; Dittmer, D. C. JOC 1991, 56, 1947.
4. (a) Jung, F.; Molin, M.; VanDer Elzen, R.; Durst, T. JACS 1974, 96, 935. (b) Harpp, D. N.; Steliou, K.; Chan, T. H. JACS 1978, 100, 1222. (c) Knittel, D.; Kastening, B. J. J. Appl. Electrochem. 1973, 3, 291. (e) Durst, T.; Charlton, J. L.; Mount, D. B. CJC 1986, 64, 246.
5. (a) Levy, L. A.; Sashikumar, V. P. JOC 1985, 50, 1760. (b) Nicolaou, K. C.; Barnette, W. E.; Ma, P. JOC 1980, 45, 1463. (c) Oppolzer, W.; Roberts, D. A.; Bird, T. G. HCA 1979, 62, 2017. (d) Nicolaou, K. C.; Barnette, W. E. CC 1979, 1119. (e) Oppolzer, W.; Roberts, D. A. HCA 1980, 63, 1703. (f) Durst, T.; Lancaster, M.; Smith, D. J. H. JCS(P1) 1981, 1846.
6. (a) Levy, L. A.; Pruitt, L. CC 1980, 227. (b) Akula, M. R.; Levy, L. A. SC 1989, 19, 2765. (c) Levy, L. A. SC 1983, 13, 639.
7. (a) Harada, N.; Sugioka, T.; Ando, Y.; Uda, H.; Kuriki, T. JACS 1988, 110, 8483. (b) du Manoir, J. R.; King, J. F.; Fraser, R. R. CC 1972, 541. (c) Cava, M. P.; Schlessinger, R. H.; Van Meter, J. P. JACS 1964, 86, 3173. (d) Schiess, P.; Rutschmann, S.; Toan, V. V. TL 1982, 23, 3665. (e) Odaira, Y.; Yamaji, K.; Tsutsumi, S. BCJ 1964, 37, 1410.
8. (a) Mann, J.; Piper, S. E. CC 1982, 430. (b) Mann, J.; Piper, S. E.; Yeung, L. K. P. JCS(P1) 1984, 2081. (c) Cava, M. P.; Mitchell, M. J.; Deana, A. A. JOC 1960, 25, 1481. (d) Lassen, N.; Ammitzboll, T. ACS 1971, 25, 2879.
9. (a) Charlton, J. L.; Plourde, G. L.; Penner, G. H. CJC 1989, 67, 1010. (b) Charlton, J. L. CJC 1986, 64, 720. (c) Charlton, J. L.; Alauddin, M. M. JOC 1986, 51, 3490. (d) Khan, Z.; Durst, T. CJC 1987, 65, 482. (e) Charlton, J. L.; Durst, T. TL 1984, 25, 2663. (f) Durst, T.; Kozma, E. C.; Charlton, J. L. JOC 1985, 50, 4829.
10. Babu, S. D.; Hrytsak, M. D.; Durst, T. CJC, 1989, 67, 1071.
11. Ibragimov, M. P.; Numanov, I. U.; Karimov, G.; Nasyrov, I. M. Dokl. Akad. Nauk Tadzh. SSR 1973, 16, 27 (CA 1974, 80, 82 552).
12. Cava, M. P.; McGrady, J. JOC 1975, 40, 72.

Donald C. Dittmer

Syracuse University, NY, USA

Copyright 1995-2000 by John Wiley & Sons, Ltd. All rights reserved.