Semiempirical Calculations on Heterodiene-Heterocumulene Cycloadditions
Walter M. F. Fabian
; Institut fiir Organische Chcmie, Karl-Franzcns-Univcristat Graz, Austria
Gert Kollenz
; Institut fiir Organische Chcmie, Karl-Franzcns-Univcristat Graz, Austria
APA 6th Edition Fabian, W.M.F. i Kollenz, G. (1992). Semiempirical Calculations on Heterodiene-Heterocumulene Cycloadditions. Croatica Chemica Acta, 65 (1), 55-67. Preuzeto s https://hrcak.srce.hr/137256
MLA 8th Edition Fabian, Walter M. F. i Gert Kollenz. "Semiempirical Calculations on Heterodiene-Heterocumulene Cycloadditions." Croatica Chemica Acta, vol. 65, br. 1, 1992, str. 55-67. https://hrcak.srce.hr/137256. Citirano 07.03.2021.
Chicago 17th Edition Fabian, Walter M. F. i Gert Kollenz. "Semiempirical Calculations on Heterodiene-Heterocumulene Cycloadditions." Croatica Chemica Acta 65, br. 1 (1992): 55-67. https://hrcak.srce.hr/137256
Harvard Fabian, W.M.F., i Kollenz, G. (1992). 'Semiempirical Calculations on Heterodiene-Heterocumulene Cycloadditions', Croatica Chemica Acta, 65(1), str. 55-67. Preuzeto s: https://hrcak.srce.hr/137256 (Datum pristupa: 07.03.2021.)
Vancouver Fabian WMF, Kollenz G. Semiempirical Calculations on Heterodiene-Heterocumulene Cycloadditions. Croatica Chemica Acta [Internet]. 1992 [pristupljeno 07.03.2021.];65(1):55-67. Dostupno na: https://hrcak.srce.hr/137256
IEEE W.M.F. Fabian i G. Kollenz, "Semiempirical Calculations on Heterodiene-Heterocumulene Cycloadditions", Croatica Chemica Acta, vol.65, br. 1, str. 55-67, 1992. [Online]. Dostupno na: https://hrcak.srce.hr/137256. [Citirano: 07.03.2021.]
Sažetak 4-Benzoyl substituted five-membered heterocyclic 2,3-diones (e.g. furan- diones or pyrrolcdiones) add various hclcrocumulcncs giving bicyclic hctcro- cyclcs. The structures of the products obtained in these reactions can be rationalized by assuming an initial [4 + 2] cycloaddition between the heterodiene system formed from the benzoyl group and the cndocyclic C = C double bond of the heterocyclic ring and the hctcrocumulcnc, followed by special and novel furandione rearrangements. Although some formal [4 + 2] cycloadditions of kctcncs are known, their reactivity is dominated by [2 + 2] cycloadditions.
For kctcnimincs, this reaction appears to be the first example of a [4 + 2] cycloaddition. Afier presenting some pertinent experimental observations semi- empirical (AMI) calculations on reactants, rcgioisomeric products and possible intermediates are discussed. As the simplest model, cycloadditions between acrolein and ketenimine arc used to locate transition states of the twelve possible peri-, site-, and rcgioisomeric products. Finally, the reliability of these calculations is discussed and some prospects for future work are given.