Dispiroketals in synthesis. Part 24.1 Preparation and use of chiral 2,2′-bis(triisopropylsilyloxymethyl)bi(dihydropyran)s as new protecting and resolving agents for 1,2-diols
Abstract
C 2 symmetric chiral 2,2′-bis(triisopropylsilyloxymethyl)bi(dihydropyran)s (S,S)-1 and (R,R)-1 were prepared from the corresponding glycidols and selectively reacted with 1,2-diols to give dispiroketals. The products of these reactions could be deprotected following treatment with fluoride, oxidation and reductive cleavage with samarium(II) iodide.