連続的炭素-炭素結合形成反応を機軸とする新規合成反応の開発研究
スポンサーリンク
概要
- 論文の詳細を見る
Development of new synthetic reactions that feature a tandem process triggered by Brook rearrangement, a C-to-O 1,2-anionic shift of a silyl group, will be discussed. A basic motif for the strategy is the generation of an α-siloxy carbanion by the reaction of acylsilanes with ketone enolates and then trapping the anions by intra- and inter-molecular electrophiles. For example, the reaction of benzoyltrimethylsilane with lithium enolates of methyl ketones produced 1,2-cyclopropanediols via Brook rearrangement of the initial 1,2-adduct and subsequent internal aldol reaction. This concept was applied to the synthesis of five- and seven-membered carbocycles using the reaction of acryloylsilanes with enolates of alkyl and alkenyl methyl ketones, respectively. Furthermore, we found that the use of enolate of 2-cycloheptenone instead of the enolates of alkenyl methyl ketone as the four-carbon unit in the [3+4] annulation produces bicyclo[3.3.2]-decenone derivatives, in which the two-atom internal tether could be cleaved to give the cis-3,4,8-trisubstituted cyclooctenone enol silyl ethers stereoselectively. The α-siloxy carbanions can be also generated by an γ-anion-induced ring cleavage of α,β-epoxysilanes. Thus, O-silyl cyanohydrins of β-silyl-α,β-epoxyaldehyde can function as a highly functionalized homoenolate equivalent via a tandem sequence involving base-promoted ring opening, Brook rearrangement, and alkylation at the allylic position. Based on these results, we developed several new synthetically useful reactions in which three methods for the generation of a carbanion at theγ-position, i.e., deprotonation, reaction of acylsilanes with a nucleophile followed by Brook rearrangement, and a conjugate addition of a nucleophile to an enoate system bearing an epoxysilane moiety at the α-position, were used.
- 公益社団法人日本薬学会の論文
- 2007-09-01
著者
関連論文
- Development of cyclic hydrazine and hydrazide type organocatalyst-mechanistic aspects of cyslic hydrazine/hydrazide-catalyzed diels-alder reactions
- ケイ素の特性を利用する有機合成反応の開発
- 周期表を読む(2)炭素,ケイ素など(1)ケイ素の特性を利用する有機合成反応の開発
- 連続的炭素-炭素結合形成反応を機軸とする新規合成反応の開発研究
- 第44回中国四国産学連携化学フォーラム
- 連続的結合形成反応を駆使する新規有機合成反応の開発
- Epoxysilane Rearrangement : Mechanistic Studies and Synthetic Applications
- ケイ素の特性を利用する炭素環形成反応の開発
- ケイ素の特性を利用する[3+2]アニュレーション法の開発とその天然物合成への応用
- Tetra-n-propy ammonium Perruthenate (TPAP)
- 薬学におけるこれからの有機化学教育
- ケイ素の特性を利用する有機合成反応の開発(講座:周期表を読む2-炭素,ケイ素など- 1)
- 立体化学的に不安定なキラルカルバニオンの合成化学への展開
- 立体化学的に不安定なキラルカルバニオンの合成化学への展開