Bench-Stable Stock Solutions of Silicon Grignard Reagents: Application to Iron- and Cobalt-Catalyzed Radical C(sp<sup>3</sup>
)-Si Cross-Coupling Reactions
作者:Weichao Xue、Ryosuke Shishido、Martin Oestreich
DOI:10.1002/anie.201807640
日期:2018.9.10
the preparation of silicon‐based magnesiumreagents is reported. The MgBr2 used in the lithium‐to‐magnesium transmetalation step is generated in situ from 1,2‐dibromoethane and elemental magnesium in hot THF. No precipitation of MgBr2 occurs in the heat, and transmetalation at elevated temperature leads to homogeneous stock solutions of the silicon Grignard reagents that are stable and storable in the
Process for preparing optically active secondary alcohols having nitrogenous or oxygenic functional groups
申请人:——
公开号:US20030045727A1
公开(公告)日:2003-03-06
A process for preparing optically active secondary alcohols of the general formula (3), [wherein R
1
is linear lower alkyl, an aromatic ring group, or the like; A is CH
2
NR
2
R
3
or the like; n is an integer of 0 to 2; and * represents an asymmetric carbon atom] by asymmetrically hydrogenating a ketone compound of the general formula (1) having nitrogenous or oxygen functional group at any of the a-, &bgr;- and &ggr;-positions, with selectivity among functional groups by the use of a ruthenium/optically active bidentate phosphine/diamine complex as the catalyst in the presence of hydrogen alone or together with a base. The optically active secondary alcohols obtained by the process are useful as drugs and intermediates for the preparation of drugs.
We describe the efficient synthesis and one‐step derivatization of novel, nonfluorescent azo dyes based on the Black Hole Quencher‐3 (BHQ‐3) scaffold. These dyes were equipped with various reactive and/or bioconjugatable groups (azido, α‐iodoacetyl, ketone, terminal alkyne, vicinal diol). The azido derivative was found to be highly reactive in the context of copper‐catalyzed azide–alkyne cycloaddition
Direct hydroxyethylation of amines by carbohydrates <i>via</i> ruthenium catalysis
作者:Le Jia、Mohamed Makha、Chen-Xia Du、Zheng-Jun Quan、Xi-Cun Wang、Yuehui Li
DOI:10.1039/c9gc01195a
日期:——
efficient and halogen-free catalytic methodology for the synthesis of β-aminoalcoholsfrom aromatic amines and biomass-derived carbohydrates is demonstrated for the first time. The activation of C5/C6 sugars by a ruthenium catalyst selectively generates the C2 alkylating reagent glycolaldehyde. The transformation involves metal-catalyzed hydrogenborrowing for the reduction of the imine intermediate. A series
frameworks (MOFs), with secondary building units (SBUs) containing a M3O (M = metal) cluster, were synthesized from identical constituents using a benzenetricarboxylate (BTC3–) linker that forms decorated 3,6- and 3,5-connected networks, respectively. There exist subtle differences between the SBUs; one of the metalatoms in the M3O cluster in the tetragonal phase has one dissociable DMF solvent molecule