Synthesis of natural products and analogs using multiple Pd-catalyzed transformations*
Lutz F. Tietze and Tom Kinzel
Institute of Organic and Biomolecular Chemistry, Georg-August-University, 37077-Göttingen, Germany
Abstract: Palladium-catalyzed transformations are of great importance in modern synthetic organic chemistry. The vast number of reactions that can be catalyzed by Pd0- as well as Pd2+-complexes in combination with the relative stability of the intermediates offers the intriguing opportunity of carrying out multiple consecutive bond-forming processes. They can be even performed in a domino fashion and in the presence of chiral ligands to allow the efficient preparation of almost enantiopure compounds. In this article, the use of double Heck, Tsuji-Trost-Heck, and Wacker-Heck reactions for the total syntheses of estradiol, spinosyn A analogs, cephalotaxine, and vitamin E is described.
Keywords: Pd0- and Pd2+-transformations; Heck; Suzuki; Stille; Sonogashira; Tsuji-Trost; Wacker oxidation; domino reactions; spinosyn A; cephalotaxine.
*Pure Appl. Chem. 79, 467-823 (2007) pp. 467-823. An issue of reviews and research papers based on lectures presented at the 25th International Symposium on Chemistry of Natural Products (ISCNP-25) and 5th International Conference on Biodiversity (ICOB-5), held jointly in Kyoto, Japan, 23-28 July 2006, on the theme of natural products.