Partial Protection of Carbohydrate Derivatives. Part 21. Lead(II) Nitrate Mediated Triisopropylsilyl Ether Formation; Preparation of 2'-Deoxy-3'-O-triisopropylsilylribonucleosides

Abstract Introduction of the triisopropylsilyl protecting group to the 3′-position of 5′-O-aroyl-2′-deoxyribonucleosides wa effectively performed by the use of triisopropylsilyl chlor ide in DMF in the presence of pyridine and lead(II) nitrate the latter was substituted in this reaction for silver nitr ate. Simple treatment of the resulting triisopropylsilyl ethers with sodium methoxide in THF gave 2′-deoxy-3′-O-tri-isopropylsilylribonucleosides in excellent yields.