Dichlorovinylene Carbonate1

[17994-23-9]  · C3Cl2O3  · Dichlorovinylene Carbonate  · (MW 154.94)

(dienophile for aromatics;1 1,2-dione synthesis;2 ketene generation3)

Alternate Name: 4,5-dichloro-1,3-dioxolen-2-one.

Physical Data: mp 19 °C; bp 39-40 °C/10 mmHg.

Solubility: sol acetone, benzene, xylene.

Preparative Method: by chlorination/dechlorination of ethylene carbonate.2,4

Handling, Storage, and Precautions: lachrymator; may be stored indefinitely in the refrigerator; slowly decomposes to CO and oxalyl chloride in the liquid state or in dilute aprotic solvents; decomposes at rt with phosphorus nucleophiles.

Reactivity Pattern.

Dichlorovinylene carbonate (1) is used primarily as a dienophile (weak) in thermal and photocycloaddition reactions. Once formed, the cycloadducts are hydrolyzed to give 1,2-dione or glyoxylic acid derivatives that are generally used as precursors of target molecules. As such, it may be considered a synthon for dicarbon suboxide (eq 1).

Cycloaddition Reactions.

Benzene, anthracene, and phenanthrene derivatives undergo cycloadditions with (1) to give 1,2- or 1,4-adducts. Acetophenone is generally used as the photosensitizer.5 Typical chemistry is illustrated (eq 2) by its photocycloaddition with benzene to give adduct (2) that was then hydrolyzed to dione (3).2

Phenanthrene and (1) give predominately one stereoisomer (shown) in a [2 + 2] photoreaction. Hydrolysis to the diketone followed by a benzilic acid rearrangement gives the cyclopropyl-a-hydroxy acid (eq 3).6

With anthracene, a thermal cycloaddition (refluxing in p-xylene) gives a 1,4-adduct (84%) and its dione (78%) upon hydrolysis (eq 4; X = H).7 Ketene derivatives are available through this chemistry (eq 4; X = OMe).3

Alkenes,8 alkynes,1,9 and dienes7,10 undergo cycloaddition as well. Eq 5 shows a two-step synthesis of a cyclobutenedione derivative11 (see N,N-Diethyl-1-propynylamine for an alternate route). Less substituted alkenes such as ethylene also work well in this type of reaction.8

Cyclopentadienes give bicyclo[2.2.1]heptenediones in thermal [4 + 2] cycloadditions (eq 6),12 where intermediate adducts are usually a mixture of endo and exo products. Addition rates depend on the cyclopentadiene used. Acyclic dienes tend to add in a [2 + 2] manner.10 Other reactions include addition to norbornenes,13 annulenes,14 3-phospholenes,15 and o-benzoquinones.16

1. Scharf, H.-D. AG(E) 1974, 13, 520.
2. McMahon, R. J.; Abelt, C. J.; Chapman, O. L.; Johnson, J. W.; Kreil, C. L.; LeRoux, J.-P.; Mooring, A. M.; West, P. R. JACS 1987, 109, 2456.
3. Pollart, D. J.; Moore, H. W. JOC 1989, 54, 5444.
4. Scharf, H.-D.; Pinske, W.; Feilen, M.-H.; Droste, W. CB 1972, 105, 554.
5. Photocycloaddition chemistry has been well studied with quantum yields and efficiencies determined for a variety of aromatics; see: (a) Scharf, H.-D.; Leismann, H.; Erb, W.; Gaidetzka, H. W.; Aretz, J. PAC 1975, 41, 581. (b) Scharf, H.-D.; Klar, R. CB 1972, 105, 575. (c) Lechtken, P.; Hesse, G. LA 1971, 754, 1.
6. Ried, W.; Schinzel, H.; Schmidt, A. H.; Schuckmann, W.; Fuess, H. CB 1980, 113, 255.
7. Scharf, H.-D.; Küsters, W. CB 1972, 105, 564.
8. Scharf, H.-D.; Droste, W.; Liebig, R. AG(E) 1968, 7, 215.
9. Scharf, H.-D.; Seidler, H. CB 1971, 104, 2995.
10. Choi, H.; Pinhas, A. R. OM 1992, 11, 442.
11. Belluš, D.; Martin, P.; Sauter, H.; Winkler, T. HCA 1980, 63, 1130.
12. Blankespoor, R. L.; Gollehon, D. JOC 1977, 42, 63.
13. (a) Ried, W.; Bellinger, O. CZ 1984, 108, 15. (b) Ried, W.; Bellinger, O.; Bats, J. W. CB 1983, 116, 3794.
14. Frauenrath, H.; Kapon, M.; Rubin, M. B. Isr. J. Chem., 1989, 29, 307.
15. Märkl, V. G.; Dannhardt, G.; Siller, J. TL 1979, 2979.
16. Jones, D. W.; Pomfret, A. JCS(P1) 1991, 13.

Kenneth C. Caster

Union Carbide Corporation, South Charleston, WV, USA

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