Science of Synthesis

Wang, S.-H.; Tu, Y.-Q.; Tang, M., Science of Synthesis: Applications of Domino Transformations in Organic Synthesis, (2015) 1, 272.

The preparation of spirocyclic diols has attracted increasing interest from organic chemists, possibly because some chiral spirocyclic diols have been used as ligands for asymmetric catalysis. Normally, such diols are prepared by reducing the corresponding spirocyclic dione, a process which typically is not very effective. Therefore, an efficient one-step approach to stereospecific spirocyclic diols from 2,3-epoxy alcohols has been developed. Upon treatment with aluminum triisopropoxide, racemic 2,3-epoxy alcohols ‌13‌ are transformed into the ring-expanded spirocyclic diol products ‌14A‌ and ‌14B‌ in one simple operation through a reductive rearrangement process (‌Scheme 4‌).[‌10‌,‌11‌]

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‌Meeeeeeeeee 8‌

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Meeeeeeeeeee Meeeeeeee

(8M*,8M*,8M*)-Meeee[8.8]eeeeeeee-8,8-eeee (‌88M‌, e = 8; e = 8); Meeeeee Meeeeeeee:[‌88‌]

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References