105(P-26) Sc(OTf)_3を用いたアルコールの新規シリルエーテル化(ポスター発表の部)
スポンサーリンク
概要
- 論文の詳細を見る
Silyl ethers are most useful and promising protecting groups of the hydroxy function in synthetic organic chemistry and various types of silyl ethers have been developed so far. Silyl ethers are usually obtained by the reaction of parent alcohols with the corresponding silyl halide in the presence of a stoichiometric amount of base, such as imidazole, 4-dimethylaminopyridine, triethylamine and so on. These silylation methods can afford the corresponding silyl ethers in high yields, but require extraction or careful filtration process to remove ammonium salts. It was reported that allylsilane had ability of silylation of alcohols under the influence of a catalytic amount of p-toluenesulfonic acid or iodine or trifluoromethanesulfonic acid (Scheme 1). These reactions proceeded with a evolution of propene gas and no any other by-product and did not need cunbersome work-up, but it was difficult to recover and reuse catalysts. On the other hand, scandium trifuoromethanesulfonate (Sc(OTf)_3), which is water stable Lewis acid, is used in various organic reactions. We have found that reaction of alcohols with methallylsilanes in the presence of a catalytic amount of Sc(OTf)_3 provides corresponding alkyl silyl ethers in high to excellent yields (Table 1). Under similar reaction conditions, silylation of tertiary alcohol proceeded smoothly and the corresponding TBS ether was obtained in high yield (Run 5). By using microencapsulated (MC) Sc(OTf)_3 (Table 2), which can be easily recovered and reused, yields of alkyl silyl ethers are improved (Runs 2-5) and the work-up after completion of the reaction is very simple.
- 天然有機化合物討論会の論文
- 2000-10-01
著者
関連論文
- 106(P-28) キラルな1,2-ジアミンを用いるアルコール類の触媒的不斉アシル化(ポスター発表の部)
- Catalytic Asymmetrization of cis-2-Cyclopentene-1,4-Diol. Highly Efficient and Practical Synthesis of (R)-4-Benzoyloxy-2-Cyclopenten-1-one
- キラルな1, 2-ジアミンを用いるアルコール類の触媒的不斉アシル化の開発
- Catalytic Asymmetric Acylation of Racemic Scondary Alcohols with Benzoyl Chloride in the Presence of a Chiral Diamine
- アルデヒドおよびアセタールからの新規複合型アリル化反応
- 105(P-26) Sc(OTf)_3を用いたアルコールの新規シリルエーテル化(ポスター発表の部)
- 精密合成における高効率ワンステップ保護基変換反応