Approaches to the synthesis of cytochalasans. Part 5. Studies on the selectivity of theDiels-Alder reaction leading to the tetrahydroiso-indolinone sub-unit

The stereo- and regiochemical course in the [2+4]cycloaddition of the chiral alkylidene malonic ester 1 to selected derivatives of (2E, 4E)-4-methyl-2, 4-hexadien-l-ol (2) and (2E, 4E)-4-methyl-2, 4-hexadien-l-al (12) has been investigated. The results are discussed on the basis of semiquantitative PMO theory.