Ferrier-type reactions synthesis

This methodology has been used for the synthesis of the C3-C14 segment 24 of the antitumor agent laulimalide 23 (Scheme 4.22) [35]. The constrained chiral BOX ligand 21c in combination with Cu(OTf)2 afforded dihydropyrane 6f by a cycloaddition reaction in good yield and ee this was converted to the C3-C14 segment 24 via a Ferrier-type rearrangement in several steps. 

Chiral cyclohexanones obtained by the Ferrier carbocyclization reaction are useful precursors for the synthesis of cyclitols and aminocyclitols, some of which are found in clinically important aminoglycoside antibiotics. Additionally, highly substituted cyclohexenones, prepared by the Ferrier carbocyclization followed by (3-elimination, can undergo various further transformations, also making these compounds potential chiral building blocks for the preparation of structurally complex compounds having cyclohexane unit(s). This section provides an overview of the reported synthetic strategies toward various types of natural products based on utilization of the Ferrier carbocyclization reaction. 

D.R. Williams and co-workers accomplished the first total synthesis of marine dolabellane diterpene (+)-4,5-deoxyneodolabelline. The Type I carbon-Ferrier reaction was utilized to assemble the key frans-2,6-disubstituted dihydropyran with complete stereoselectivity (a-anomer). The macrocyclization was carried out with a vanadium-based pinacoi coupiing. 

A gold catalysis-initiated cascade process toward the synthesis of electron-rich arene-fused hexahydroquinolizinones 131 was developed by Zhang and Liu in 2012 (Scheme 12.57) [62]. In this cascade reaction, a gold-catalyzed amide cyclization to a tethered C-C triple bond initiates a subsequent Frie del-Crafts type cyclization, followed by a Ferrier rearrangement. Synthetic utility of this... 

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