Stereoselective synthesis halogenated natural products

In this chapter, the applications of stereoselective halogenations (C—Cl, C—Br, and C—I) in the total synthesis of natural or bioactive organohalogens will be shown. The main focus of this chapter will be on the enantioselective synthesis of natural products and bioactive molecules... 

STEREOSELECTIVE SYNTHESIS OE HALOGENATED NATURAL PRODUCTS TABLE 43.2. Enantioselective Halogenation of (J-Ketoesters... 

The total synthesis of the marine natural product (5Z)-dactomelyne (1) requires the elaboration of the c -linked pyranopyran skeleton and the stereoselective introduction of halogen atoms on the tetrahydropyran rings. Lee et al. [2] solved this problem by using of )9-alkoxy-acrylates twice as radical acceptors (Scheme 1). 

Halogenated alkenols are versatile synthetic intermediates as well as critical structural units in a variety of biologically active natural products. Previous preparations of these structures are often hampered by multistep synthesis and by poor stereoselectivity. The Nozaki-Hiyama reaction has provided good synthetic entry to these structures. For example, a highly... 

In the history of syntheses of halogen-containing molecules, an early approach to effect the stereoselective halogenation is via substrate control. This section will describe various substrate-controlled stereoselective halogenations found in natural product synthesis. 

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