Diels-Alder reaction rules governing

Indeed, it seems that intramolecular Diels-Alder reactions are governed more by normal steric considerations than by the endo rule. 

When the diene and the dienophile are already part of the same molecule it is not so important for them to be held together by bonding interactions across space and the exo product is often preferred. Indeed, many intramolecular Diels-Alder reactions are governed more by normal steric considerations than by the endo rule. 

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. 

Specific rules governing the Diels-Alder reaction... 

Specific Rules Governing the Diels-Alder Reaction... 

Alder-Stein rules. Set of rules governing the stereochemistry of the Diels-Alder reaction. The most important are that (1) the stereochemical relationship of groups attached to the diene and the dienophile is maintained in the product (cis-addi-tion) and (2) the product resulting from maximum accumulation of unsaturated centers in the transition state is favored (endo rule). 

Woodward and Roald Hoffmann, Nobel prize winners for their work, formulated the theoretical rules involving the correlation of orbital symmetry, which govern the Diels-Alder and other electrocyclic reactions. 

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