Photoisomerization of Carbon-Carbon Double Bonds as Key Step in Organic Synthesis

JAVIER I. BARDAGÍ; SOFÍA CAVÍ; SILVIA SORIA CASTRO; GABRIELA OKSDATH MANSILLA*

Photoisomerization: Causes, Behavior and Effects

NOVA SCIENCE PUBLISHERS, INC.

Lugar: Nueva York; Año: 2019; p. 239 - 270

Synthetic organic photochemistry constitutes an active research area and powerful tool for the preparation of natural products as well as others molecules with high structural complexity, in a simple way under mild conditions. In this context, numerous light promoted transformations are reported every year demonstrating the versatility and scope of the photochemical reactions.In particular, photoisomerization of double bonds has been extensively studied evaluating the conformational or geometrical changes induced on the molecule. However, spatiotemporal control of specific alkene geometry has attractive interest in organic synthesis, especially when the success of a desired transformation depend on a predefined configuration. There are many synthetic strategies which involve the photoisomerization as a key step to access to new molecular structures, proving the synthetic potential of this reaction. Therefore, in this chapter we focus on the synthetic point of view of photoisomerization as efficient method to facilitate a spatiotemporal control of an alkene, at a defined stage of a synthetic sequence. The synthetic aspects of light-induced isomerization will be described, evaluating its participation in combination with other reactions such as cyclization, Pd-catalysis, radical addition, hydroamination or Stetter reaction. Using an appropriate synthetic strategy, valuable derivatives such as phenanthridinones, quinolinones, cyclic and spirocyclic ketals, chromenes or coumarin can be obtained. Furthermore, photoisomerization applied to the synthesis of natural product or molecules with biological relevance are discussed.