applied to a catalytic asymmetric nitrene-transfer reaction with enolsilylethers. The ruthenium catalyst was applicable to aliphatic enolsilylethers as well as aryl-containing enolsilylethers. The substrate scope of the ruthenium catalyst was superior to that of analogous chiral paddle-wheel rhodium catalysts. α-Amino ketonesderivedfrom aliphatic substrates were obtained in up to 97% ee with the
将手性桨轮双核钌催化剂应用于与烯醇甲硅烷基醚的催化不对称氮烯转移反应。钌催化剂适用于脂肪族烯醇硅醚以及含芳基的烯醇硅醚。钌催化剂的底物范围优于类似的手性桨轮铑催化剂。使用钌催化剂可获得高达 97% ee 的源自脂肪族底物的 α-氨基酮,而类似的铑催化剂仅产生适度的对映选择性。
Selective Halogen−Magnesium Exchange Reaction via Organomagnesium Ate Complex
Halogen-magnesium exchange of various aryl halides is achieved with a magnesium ate complex at low temperatures; Tributylmagnesate ((Bu3MgLi)-Bu-n) induces facile iodine-magnesium exchange at -78 degreesC. Dibutylisopropylmagnesate ((PrBu2MgLi)-Pr-i-Bu-n) is more reactive than (Bu3MgLi)-Bu-n, and this reagent accomplishes selective bromine-magnesium exchange at -78 degreesC. This procedure is utilized for the preparation of various polyfunctionalized arylmagnesium species. The exchange of alkenyl halides using this method proceeds with retention of configuration of the double bond.
Structurally constrained C1-1,1′-bisisoquinoline-based chiral ligands: geometrical implications on enantioinduction in the addition of diethylzinc to aldehydes
作者:Gao Qi、Zaher M.A. Judeh
DOI:10.1016/j.tetasy.2010.02.022
日期:2010.3
New highly constrained chiral C-1-1,1'-bisisoquinoline ligands have been synthesized. X-ray crystallographic analysis of these ligands showed peculiar structural differences between the parent 1',2',3',4'-tetrahydro-1,1'-bisisoquinoline and its alkyl, acyl and sulfonyl derivatives. The consequences of their geometrical conformations on enantioinduction were examined by employing the enantioselective addition of diethylzinc to aldehydes. Such conformations greatly affected the catalytic efficiency of these ligands. (C) 2010 Elsevier Ltd. All rights reserved.
COMPOSITION FOR FORMING RESIST UNDERLAYER
申请人:AZ ELECTRONIC MATERIALS (LUXEMBOURG) S.A.R.L.
公开号:US20150118624A1
公开(公告)日:2015-04-30
The present invention provides a dendrimer compound capable of improving critical dimension uniformity and DOF (depth of focus) margin, and also provides a composition capable of forming an underlayer film. The dendrimer compound comprises a branched chain having a central aromatic skeleton and amide or ester bond, and is contained in the composition for forming an underlayer film.