Diastereoselective Total Synthesis of Raputindole A
作者:Mario Kock、Thomas Lindel
DOI:10.1021/acs.orglett.8b02349
日期:2018.9.7
The first diastereoselective total synthesis of the bisindole alkaloid raputindole A is reported. After Au(I)-catalyzed assembly of the cyclopenta[f]indole tricycle, it was possible to hydrogenate the indene double bond regio- and diastereoselectively through iridium catalysis, guided by a preinstalled hydroxy function. Attempted HWE reaction led to formal elimination of formaldehyde from an α-quaternary
报道了双吲哚生物碱拉普吲哚A的第一个非对映选择性全合成。在Au(I)催化的环戊[ f ]吲哚三环的组装后,可以在预先安装的羟基官能团的引导下,通过铱催化将茚双键区域和非对映选择性地氢化。尝试的HWE反应导致从α-季环戊烷甲醛中甲醛的正式消除,而Takai烯烃化可避免甲醛的发生。在Suzuki-Miyaura交叉偶联和脱保护/氧化后,以13个线性步骤获得了(±)-raputindole A,总产率为18%。
Tertiary alcohol synthesis from secondary alcohols via C–H insertion
作者:Eun Lee、Insung Choi、Sue Yeon Song
DOI:10.1039/c39950000321
日期:——
Secondary alcohols are converted into 3(2H)-furanone derivatives via CâH insertion reaction, from which tertiary alcohols are prepared with retention of stereochemistry.
Aldol reactions of titanium enolates of lactate-derived ethylketone 1 with other ketones proceed in a very efficient and stereocontrolled manner provided that a further equivalent of TiCl4 is added to the reacting mixture. The scope of these reactions encompasses simple ketones such as acetone or cyclohexanone as well as other ketones that contain potential chelating groups such as pyruvate esters
Diastereoselectivity in the Carroll rearrangement of β-keto esters of tertiary allylic alcohols
作者:Michael E. Jung、Brian A. Duclos
DOI:10.1016/j.tetlet.2003.10.102
日期:2004.1
Carroll rearrangement of β-keto esters derived from tertiary allylic alcohols, for example, 7, under basic conditions followed by decarboxylation of the resulting β-keto acids yielded the expected γ,δ-unsaturated methyl ketones 8 with a range of olefin geometries from 100:0 to 1:1.8 E/Z, depending on the relative steric requirements of the two groups at the allylic center.
在碱性条件下,衍生自叔烯丙醇的β-酮酯(例如7)的Carroll重排,然后将所得的β-酮酸脱羧,得到预期的γ,δ-不饱和甲基酮8,其烯烃几何结构范围为100 :0到1:1.8 E / Z,取决于在烯丙基中心的两组的相对空间要求。
Hydride reduction of alpha, beta-unsaturated carbonyl compounds using chiral organic catalysts
申请人:MacMillan David
公开号:US20060161024A1
公开(公告)日:2006-07-20
Nonmetallic, chiral organic catalysts are used to catalyze the 1,4-hydride reduction of an α,β-unsaturated carbonyl compound. The α,β-unsaturated carbonyl compound may be an aldehyde or cyclic ketone, and the hydride donor may be a dihydropyridine. The reaction is enantioselective, and proceeds with a variety of hydride donors, catalysts, and substrates. The invention also provides compositions effective in carrying out the 1,4-hydride addition of α,β-unsaturated carbonyl compounds.