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991.
The synthesis of phosphane‐ene photopolymer networks, where the networks are composed of crosslinked tertiary alkyl phosphines are reported. Taking advantage of the rich coordination chemistry of alkyl phosphines, stibino‐phosphonium and stibino‐bis(phosphonium) functionalized polymer networks could be generated. Small‐molecule stibino‐phosphonium and stibino‐bis(phosphonium) compounds have been well characterized previously and were used as models for spectroscopic comparison to the macromolecular analogues by NMR and XANES spectroscopy. This work reveals that the physical and electronic properties of the materials can be tuned depending on the type of coordination environment. These materials can be used as ceramic precursors, where the Sb‐functionalized polymers influence the composition of the resulting ceramic.  相似文献   
992.
Reported is a modular one‐step three‐component synthesis of tetrahydroisoquinolines using a Catellani strategy. This process exploits aziridines as the alkylating reagents, through palladium/norbornene cooperative catalysis, to enable a Catellani/Heck/aza‐Michael addition cascade. This mild, chemoselective, and scalable protocol has broad substrate scope (43 examples, up to 90 % yield). The most striking feature of this protocol is the excellent regioselectivity and diastereoselectivity observed for 2‐alkyl‐ and 2‐aryl‐substituted aziridines to access 1,3‐cis‐substituted and 1,4‐cis‐substituted tetrahydroisoquinolines, respectively. Moreover, this is a versatile process with high step and atom economy.  相似文献   
993.
A key bottleneck in the profiling of lipids is the multistep derivatization required prior to gas chromatography (GC) analysis. A single in-vial lipid derivatization and analysis may significantly minimize sample loss and improve analytical sensitivity. A cotton fiber-supported poly(glycidylmethacrylate-co-ethylene glycol dimethacrylate) polymer microbrush microreactor loaded with Candida antarctica lipase B was developed for the facile conversion of triacylglycerols into fatty acid ethyl ester derivatives for gas chromatograph–mass spectrometry (GC–MS) analysis. The polymer microbrush microreactor was fabricated in effort to provide efficient, simplified, cost effective, and high-throughput GC–MS determination of triacylglycerols. The polymer microbrush microreactor was used as an in-vial triacylglycerol transesterification platform, with economical sample consumption of less than or equal to 100?µL and significant reduction of reagents. To evaluate the polymer microbrush microreactor performance for lipids, a triolein standard and camelina oil triacylglycerols were quantitatively transformed into ethyl oleate and fatty acid ethyl esters, respectively, following a 3?h reaction time. The lipase-loaded cotton fiber-supported poly(glycidylmethacrylate-co-ethylene glycol dimethacrylate) polymer microbrush microreactors were reusable for up to five times for quantitative transesterification with minimal loss of lipase activity.  相似文献   
994.
In the title compound, [Fe(C5H5)(C16H12N3OS)], the 8‐am­inoquinoline and acyl­thio­urea moieties are almost planar. There are two perpendicular arrangements of the mol­ecules in the crystal with slightly different conformations. The two cyclo­penta­dienyl rings in each mol­ecule are parallel and eclipsed.  相似文献   
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The synthesis of 3‐aryl‐2‐cyclohexenones is a topic of current interest as they are not only privileged structures in bioactive molecules, but they are also relevant feedstocks for the synthesis of substituted phenols or anilines, which are ubiquitous structural elements both in drug design and medicinal chemistry. A simple and sustainable one‐pot aerobic double dehydrogenative reaction under mild conditions for the introduction of arenes in the β‐position of cyclic ketones has been developed. Starting from the corresponding saturated ketone, this reaction sequence proceeds under relatively low Pd catalyst loading and involves catalytic amounts of electron‐transfer mediators (ETMs) under ambient oxygen pressure.  相似文献   
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