Ferroelectric Liquid Crystals. 6. Synthesis of Nonracemic Aryl Cyanohydrin Ethers

Article abstract of DOI:10.1021/jo00281a042

In connection with our project directed toward the design and synthesis of high-performance ferroelectric liquid crystals, we have developed a generally applicable synthetic route to chiral nonracemic cyanohydrin ethers.The synthesis is illustrated herin by preparation of the arylbenzoate 1 (R₁ = n-decyl, R₂ = n-pentyl), which results in a straightforward manner benzoylation of the key phenol intermediate 7.Phenol 7 derives from Mitsunobu coupling of p-(benzoyloxy)phenol (3) with nonracemic N-(α-hydroxyacyl)oxazolidone 2 prepared by the method of Evans.It is shown that this coupling proceeds predominantly with inversion of configuration.Conversion of resulting N-(α-(aryloxy)acyl)oxazolidone 4 to amide 5 by treatment with dimethylaluminum amide, dehydration to nitrile 6 by the action of trimethylsilyl polyphosphoric acid, and then debenzylation promoted by the trimethylsilyl iodide gives 7 in 51percent overall yield from 2.