Synthesis of pentacyclic compounds via intramolecular [3 + 2] photocycloaddition of cycloalkene linked naphthalenes

Synthetic Approaches to Natural and Unnatural Tetraquinanes

“…addition of 1-cyanonaphthalene containing cyclopentane ring system produced the hexacyclic photoadduct 120 as a major product (Scheme 19). [15] Fenestrane Type Tetraquinanes…”

“…To this end, [3+2] intramolecular cycloaddition of 1‐cyanonaphthalene containing cyclopentane ring system produced the hexacyclic photoadduct 120 as a major product (Scheme 19). [15] …”

Synthesis of 3‐Oxatricyclo[7.2.0.01,5]undeca‐7,10‐dienes through Intramolecular Photocycloaddition Reactions of Alkenes to 1,8 a‐Position of Naphthalene Ring

“…Reaction at the 1,3-position via a biradical leads to compounds having a 3oxatricyclo[3.3.0.0 2,8 ]oct-3-ene skeleton, which was also shown in our earlier extensive studies. [17,44,66,67,[70][71][72][73][74] The reaction at the 1,4-position (photo-Diels-Alder reaction) proceeds stepwise mainly via excited triplet state. [33,40,44,52,56,60,65,70,71,[75][76][77][78][79][80] In the reaction at the 1,8-position, tetrahydroacenaphthylene deriva-yields of 1,8a-adduct and secondary products is reported to be at most 30 % or less.…”

Intramolecular Photoreactions of 9-Cyanophenanthrene-Linked Arylcyclopropanes

“…In contrast to their intermolecular counterparts, intramolecular reactions often proceed with increased efficiencies and high levels of regio- and stereoselectivity owing to the entropic and preorientaion effects. 13 We have also encountered these phenomena in recent studies of linked naphthalene-cyclopropane derivatives that undergo intramolecular [3 + 2] and [4 + 3] photocycloaddition reactions with high levels of regio- and stereochemical control. 14 The earlier results prompted us to investigate the photochemistry of 9-cyanophenanthrene–arylcyclopropane-linked systems because of several reasons including the expectations that the extended π-system in the phenanthrene ring would enable ready formation of intramolecular exciplexes 15 and that reactions of the exciplexes would lead to complex polycyclic ring systems that are difficult to prepare using other approaches.…”

“…In contrast to their intermolecular counterparts, intramolecular reactions often proceed with increased efficiencies and high levels of regio- and stereoselectivity owing to the entropic and preorientaion effects . We have also encountered these phenomena in recent studies of linked naphthalene-cyclopropane derivatives that undergo intramolecular [3 + 2] and [4 + 3] photocycloaddition reactions with high levels of regio- and stereochemical control .…”