The Cope rearrangements of bicyclo[5.1.0]octa-2,5-diene and its 4-hetero-(aza/oxa/phospha) and 4,8-dihetero analogues were investigated using density functional theory at the B3LYP/6–31+G* level in gas phase. The rearrangements of bicyclo[5.1.0]octa-2,5-diene and its symmetrical 4,8-dihetero analogues followed a concerted mechanism involving synchronous transition states. In other cases, although a concerted mechanism was observed, asynchronous transition states were involved. In the case of bicyclo[5.1.0]octa-2,5-diene, a degenerate Cope rearrangement was expected to occur at room temperature (25°C) due to a low free activation energy (ΔG^‡ = 14.46 kcal mol^–1). However, under similar conditions, the rearrangement of 4,8-dioxabicyclo[5.1.0]octa-2,5-diene was much slower (ΔG^‡ = 23.85 kcal mol^–1) and the 4,8-diaza- and diphospha analogues did not undergo Cope rearrangement. The Cope rearrangements of 4-phospha-, 8-aza-, 8-aza-4-oxa-, 8-aza-4-phospha-, and 8-oxa-4-phospha-bicyclo[5.1.0]octa-2,5-dienes were exergonic and were expected to occur spontaneously to form the corresponding products. In contrast, rearrangement of 8-oxabicyclo[5.1.0]octa-2,5-diene, though exergonic, was accompanied by a decrease in entropy, due to which Cope rearrangement would occur much more slowly and a mixture of both valence isomers would be formed. The Cope rearrangements of 4-aza-, 4-oxa-, 4-aza-8-oxa-, 8-phospha-, 4-aza-8-phospha-, 4-oxa-8-phospha-, and 4,8-diphospha-bicyclo[5.1.0]octa-2,5-dienes were endergonic; consequently either no Cope rearrangement would take place or it would occur sluggishly.

使用密度泛函理论在B3LYP / 6–31上研究了双环[5.1.0] octa-2,5-二烯及其4-杂-（氮杂/氧杂/磷）和4,8-二杂类似物的Cope重排。气相中的+ G *水平。双环[5.1.0] octa-2,5-diene及其对称的4,8-dihetero类似物的重排遵循涉及同步跃迁状态的协调机制。在其他情况下，尽管观察到协调的机制，但涉及异步转换状态。在双环[5.1.0] octa-2,5-diene的情况下，由于低的自由活化能（ΔG ^‡  = 14.46 kcal mol ，预计在室温（25°C）发生简并的Cope重排^{– 1}）。但是，在相似的条件下，4,8-二氧杂双环[5.1.0] octa-2,5-diene的重排要慢得多（ΔG ^‡  = 23.85 kcal mol ^–1）和4,8-二氮杂和二磷类似物未进行Cope重排。4-磷酸，8-氮杂，8-氮杂-4-氧杂，8-氮杂-4-磷杂和8-氧-4-磷杂双环[5.1.0] octa-2的Cope重排1,5-二烯是强力的，预期会自发形成相应的产物。相比之下，尽管8-氧杂双环[5.1.0] octa-2,5-二烯是重能性的，但其重排伴随着熵的降低，因此，Cope重排的发生要慢得多，并且两种价异构体的混合物也会形成。4-氮杂，4-氧杂，4-氮杂-8-杂，8-磷，4-氮杂-8-，4-氧八-和4,8的Cope重排-二磷-双环[5.1.0] octa-2,5-二烯是发光的；因此，要么没有Cope重排发生，要么缓慢发生。