Evidence for the existence of the dianion of cyclobutadiene

Journal of the Chemical Society, Chemical Communications

Volumn 0, Issue 7, 1972, Pages 365-366

  McKennis, J S ^a   Brener, Lazaro ^a   Schweiger, J R ^a   Pettit, R ^a  

^a UNIVERSITY OF TEXAS AT AUSTIN   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 37049142130     PISSN: 00224936     EISSN: None     Source Type: Journal    
DOI: 10.1039/C39720000365     Document Type: Article

References (11)

1. T. J. Katz, J. Amer. Chem. Soc., 1960, 82, 3784.
2. An unsuccessful attempt to prepare the dianion of tetramethylcyclobutadiene has been reported (W. Adam, Tetrahedron Letters, 1963, 1387). Our results suggest that this dianion might have, in fact, been prepared but owing to its high reactivity escaped detection.
3. The deuterium content of the cyclobutene was measured by n.m.r. and by both high resolution and low voltage mass spectroscopy.
4. All other compounds were identified by comparison of their spectra and/or retention times with those of authentic samples.
5. J. F. Garst, Accounts Chem. Res., 1971, 4, 400.
6. E. K. G. Schmidt, L. Brener, and R. Pettit, J. Amer. Chem. Soc., 1970, 92, 3240.
7. An analogous ring opening of a cyclobutenyl anion has been reported.
8. H. H. Freedman, G. A. Doorakian, and V. R. Sandel, J. Amer. Chem. Soc., 1965, 87, 3019.
9. Reaction of trans, trans-1, 4-dichlorobutadiene with sodium naphthalide under our reaction conditions does afford a mixture of cis- and trans-but-2-enes.
10. For example, part of the tricyclo-octadienes could result from dimerization of the chlorocyclobutenyl radical followed by Wurtz type coupling.
11. There is ample evidence that carbanions can abstract protons from ethereal solvents.