Type II Ferrier

The highly oxygenated sesquiterpene paniculide A was synthesized by N. Chida et al. starting from D-glucose. The key step to construct the substituted cyclohexane subunit of the natural product involved the Type II Ferrier rearrangement. 

The stereoselective total synthesis of antimitotic alkaloid (+)-lycoricidine was accomplished by S. Ogawa and coworkers by utilizing the catalytic version of the Type II Ferrier rearrangement for the synthesis of the optically active... 

The Ferrier (II) reaction is quite efficient to form six membered carbocycles, but is unsuitable to prepare cyclopentitols. Five membered enollactone 14 was converted to the cyclopentanone derivative 16 as a single epimer upon treatment by LiAlH(OtBu)3 (Scheme 4) [41]. Spectroscopic studies established some mechanistic details. Accordingly, the hydride of the reducing agent rapidly added to the carbonyl and formed with the metal a stable alu-minate complex. The carbocydization occurred by protonation followed by fragmentation and aldol type cyclization process. 

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