| 释义 |
pericyclic, a. Chem.|pɛrɪˈsaɪklɪk|
[f. peri- + cyclic a.]
Of a reaction: involving a concerted rearrangement of bonding in which all the bonds broken or formed in the reaction lie on a closed ring, whether or not a cyclic molecule is involved.
1969Woodward & Hoffmann in Angewandte Chemie (Internat. Ed.) VIII. 848/1 In our development of the theme of orbital symmetry control of concerted chemical changes, we have laid the basis for a general consideration of all pericyclic reactions—that is, reactions in which all first-order changes in bonding relationships take place in concert on a closed curve. 1974Gill & Willis Pericyclic Reactions iv. 99 The basic tenet of the Woodward-Hoffmann theory is that orbital symmetry is conserved in concerted pericyclic reactions. Ibid. vi. 162 The six-electron cyclo-addition and reversion processes are by far the most common of all pericyclic changes... Within this category falls the well-known Diels-Alder reaction. 1975W. R. Dolbier in Buncel & Lee Isotopes in Org. Chem. I. ii. 27 The class of reactions which are presently known as pericyclic or multi-centered reactions..include cyclo-additions, electrocyclic reactions and sigmatropic processes. |