Reactions involving cyclic transition states

No new reaction involving cyclic transition states was reported for not fully conjugated systems during the period of time covered. 

Reactions Involving Cyclic Transition States 5.06.3.8.1 Dipolar additions to thiirene 1-oxides and 1,1-dioxides... 

Oxidations, reductions and reactions involving cyclic transition states 563... 

Several types of reaction involving cyclic transition states are known. 

We summarize here a procedure to predict the feasibility and the stereochemistry of thermally concerted reactions involving cyclic transition states. The 1,2 rearrangement of carbocations will be used to illustrate the approach. This is a very important reaction of carbocations which we have discussed in other chapters. We use it here as an example to illustrate how qualitative MO theory can give insight into how and why reactions occur ... 

Reactions Involving Cyclic Transition States - Dipolar Addition to Thiirene-1 -Oxides... 

There are a number of concerted reactions involving cyclic transition states which are characterized by the maintenance throughout of an overlap between orbitals of the correct symmetry. These reactions are known as pericyclic reactions and the rules that govern them are known as the Woodward-Hoffmann rules. A typical example of a reaction of this type is the Diels-Alder reaction of a diene and a dienophile. 

---