在氯化锂和新戊酸镁(Mg(OCO t Bu)2)在THF中存在的情况下,用锌粉处理各种烯丙基氯化物或溴化物,可得到烯丙基锌试剂,该溶剂蒸发后,生成的固态锌试剂显示出优异的热稳定性。这些烯丙基试剂与PEPPSI-IPent进行Pd催化的交叉偶联反应,以及对芳基酮和醛进行高度区域选择性和非对映选择性的加成。酰化与各种酰氯区域选择性地产生相应的高烯丙基酮,用新的C C键总是被形成在烯丙基系统的最受阻碳。
Diastereoselective Synthesis of Homoallylic Alcohols with Adjacent Tertiary and Quaternary Centers by Using Functionalized Allylic Aluminum Reagents
作者:Zhihua Peng、Tobias D. Blümke、Peter Mayer、Paul Knochel
DOI:10.1002/anie.201003813
日期:2010.11.2
Sensitive functional groups, including ester and cyano groups, can be present in allylicaluminumreagents prepared by aluminum insertion in the presence of InCl3. These aluminum organometallic compounds undergo addition reactions to various functionalized aldehydes or ketones with remarkable diastereoselectivities allowing the construction of two adjacentquaternary and tertiarycenters (see scheme)
[EN] ORGANOZINC REAGENTS AND PROCESSES FOR PREPARING AND USING THE SAME<br/>[FR] RÉACTIFS ORGANOZINCIQUES ET LEURS PROCÉDÉS DE PRÉPARATION ET D'UTILISATION
申请人:UNIV MUENCHEN LUDWIG MAXIMILIANS
公开号:WO2016146689A1
公开(公告)日:2016-09-22
Provided is an organozinc composition comprising (a) an organozinc complex carrying an allylic ligand, (b) a magnesium component and (c) a lithium component. The organozinc composition is useful as a synthetic intermediate with excellent reactivity and selectivity, and can be stored for extended periods of time without loss of activity. Moreover, a process for the preparation of the organozinc composition and synthetic procedures making use of the organozinc composition are provided.
作者:Mario Ellwart、Ilya S. Makarov、Florian Achrainer、Hendrik Zipse、Paul Knochel
DOI:10.1002/anie.201603923
日期:2016.8.22
Readily prepared allylic zinc halides undergo SN2‐type substitutions with allylic bromides in a 1:1 mixture of THF and DMPU providing 1,5‐dienes regioselectively. The allylic zinc species reacts at the most branched end (γ‐position) of the allylic system furnishing exclusively γ,α′‐allyl–allyl cross‐coupling products. Remarkably, the double bond stereochemistry of the allylic halide is maintained during
现成的烯丙基卤化锌在THF和DMPU的1:1混合物中用烯丙基溴进行S N 2型取代,可选择性地提供1,5二烯。烯丙基锌物种在烯丙基体系的最分支末端(γ位置)反应,专门提供γ,α'-烯丙基-烯丙基交叉偶联产物。值得注意的是,烯丙基卤的双键立体化学在交叉偶联过程中得以保持。还可以耐受几个官能团(酯,腈)。烯丙基锌试剂的这种交叉偶联可以扩展到炔丙基和苄基卤化物。DFT计算显示了氯化锂在该替代中的重要性。
Palladium-Catalyzed Asymmetric Synthesis of Allylic Fluorides
作者:Matthew H. Katcher、Abigail G. Doyle
DOI:10.1021/ja109120n
日期:2010.12.15
The enantioselective fluorination of readily available cyclic allylic chlorides with AgF has been accomplished using a Pd(0) catalyst and Trost bisphosphine ligand. The reactions proceed with unprecedented ease of operation for Pd-mediated nucleophilic fluorination, allowing access to highly enantioenriched cyclic allylicfluorides that bear diverse functional groups. Evidence that supports a mechanism
Organozinc reagents and processes for preparing and using the same
申请人:Ludwig-Maximilians-Universität München
公开号:EP3070083A1
公开(公告)日:2016-09-21
Provided is an organozinc composition comprising (a) an organozinc complex carrying an allylic ligand, (b) a magnesium component and (c) a lithium component. The organozinc composition is useful as a synthetic intermediate with excellent reactivity and selectivity, and can be stored for extended periods of time without loss of activity. Moreover, a process for the preparation of the organozinc composition and synthetic procedures making use of the organozinc composition are provided.