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161.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(19):5388-5391
Intramolecular benzoin reactions catalyzed by benzaldehyde lyase from Pseudomonas fluorescens biovar I (BAL) are reported. The structure of the substrates envisaged for this reaction consists of two benzaldehyde derivatives linked by an alkyl chain. The structural requirements needed to achieve the intramolecular carbon–carbon bond reaction catalyzed by BAL were established. Thus, a linker consisting of a linear alkyl chain of three carbon atoms connected through ether‐type bonds to the 2 and 2′ positions of two benzaldehyde moieties, which could be substituted with either Cl, Br, or OCH3 at either the 3 and 3′ or 5 and 5′ positions, were suitable substrates for BAL. Reactions with 61–84 % yields of the intramolecular product and ee values between 64 and 98 %, were achieved. 相似文献
162.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(25):7311-7314
The borylation of C−H bonds catalyzed by transition metals has been investigated extensively in the past two decades, but no iridium‐catalyzed enantioselective borylation of C−H bonds has been reported. We report a set of iridium‐catalyzed enantioselective borylations of aromatic C−H bonds. This reaction relies on a set of newly developed chiral quinolyl oxazoline ligands. This process proceeds under mild conditions with good to excellent enantioselectivity, and the borylated products can be converted to enantioenriched derivatives containing new C−O, C−C, C−Cl, or C−Br bonds. 相似文献
163.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(35):10587-10592
The enantioselective N‐alkylation of indole and its derivatives with aldimines is efficiently catalyzed by a zinc‐ProPhenol dinuclear complex under mild conditions to afford N‐alkylated indole derivatives in good yield (up to 86 %) and excellent enantiomeric ratio (up to 99.5:0.5 e.r.). This method tolerates a wide array of indoles, as well as pyrrole and carbazole, to afford the corresponding N‐alkylation products. The reaction can be run on a gram scale with reduced catalyst loading without impacting the efficiency. The chiral aminals were further elaborated into various chiral polyheterocyclic derivatives. The surprising stability of the chiral N‐alkylation products will open new windows for asymmetric catalysis and medicinal chemistry. 相似文献
164.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(49):15761-15765
Histone lysine demethylases (KDMs) are of critical importance in the epigenetic regulation of gene expression, yet there are few selective, cell‐permeable inhibitors or suitable tool compounds for these enzymes. We describe the discovery of a new class of inhibitor that is highly potent towards the histone lysine demethylases KDM2A/7A. A modular synthetic approach was used to explore the chemical space and accelerate the investigation of key structure–activity relationships, leading to the development of a small molecule with around 75‐fold selectivity towards KDM2A/7A versus other KDMs, as well as cellular activity at low micromolar concentrations. 相似文献
165.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(39):12148-12151
Trifluoromethoxy‐substituted stereogenic centers can be constructed with high enantioselectivity by a nickel‐catalyzed Suzuki–Miyaura coupling of readily available α‐bromobenzyl trifluoromethyl ethers with a variety of aryl pinacol boronates. The coupling proceeds under mild reaction conditions, and a variety of common functional groups, such as fluoride, chloride, bromide, ester, enolizable ketone, nitro, cyano, amino, and vinyl moieties, were well tolerated. Furthermore, the reaction can be easily scaled up to gram quantities without a decrease in enantioselectivity. 相似文献
166.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(31):9335-9338
An enantioselective C−H addition to a C=C bond represents the most atom‐efficient route for the construction of chiral carbon–carbon skeletons, a central research topic in organic synthesis. We herein report the enantioselective yttrium‐catalyzed C(sp3)−H bond addition of 2‐methyl azaarenes, such as 2‐methyl pyridines, to various substituted cyclopropenes and norbornenes. This process efficiently afforded a new family of chiral pyridylmethyl‐functionalized cyclopropane and norbornane derivatives in high yields and high enantioselectivities (up to 97 % ee ). 相似文献
167.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(42):13287-13291
The first enantioselective conjugate addition of silyl ketene imines to in situ generated indol‐2‐ones was performed in the presence of a chiral N ,N ′‐dioxide/NiII catalyst. This method provides efficient access to chiral β‐alkyl nitriles bearing congested vicinal all‐carbon quaternary stereocenters in up to 90 % yield with 23:1 d.r. and 98 % ee . The products enable facile transformations to chiral pyrroloindoline frameworks and spirocyclohexane oxindole derivatives. A possible transition state was also proposed to explain the origin of the asymmetric induction. 相似文献
168.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(40):12374-12377
Reported is the enantioselective synthesis of tetracyclic indolines using silver(I)/chiral phosphoric acid catalysis. A variety of alkyne‐tethered indoles are suitable for this process. Mechanistic studies suggest that the in situ generated silver(I) chiral phosphate activates both the alkyne and the indole nucleophile in the initial cyclization step through an intermolecular hydrogen bond and the phosphate anion promotes proton transfer. In addition, further modifications of the cyclization products enabled stereochemistry–function studies of a series of bioactive indolines. 相似文献
169.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(39):12032-12036
Catalytic enantioselective conjunctive cross‐coupling between 9‐BBN borate complexes and aryl electrophiles can be accomplished with Ni salts in the presence of a chiral diamine ligand. The reactions furnish chiral 9‐BBN derivatives in an enantioselective fashion and these are converted to chiral alcohols and amines, or engaged in other stereospecific C−C bond forming reactions. 相似文献
170.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(30):9013-9017
Enantioselective allylic substitution with enolates derived from aliphatic esters under mild conditions remains challenging. Herein we report iridium‐catalyzed enantioselective allylation reactions of silyl ketene acetals, the silicon enolates of esters, to form products containing a quaternary carbon atom at the nucleophile moiety and a tertiary carbon atom at the electrophile moiety. Under relatively neutral conditions, the allylated aliphatic esters were obtained with excellent regioselectivity and enantioselectivity. These products were readily converted into primary alcohols, carboxylic acids, amides, isocyanates, and carbamates, as well as tetrahydrofuran and γ‐butyrolactone derivatives, without erosion of enantiomeric purity. 相似文献