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101.
Richard M. Gauld Dr. Ross McLellan Dr. Alan R. Kennedy Dr. Jim Barker Dr. Jacqueline Reid Prof. Dr. Robert E. Mulvey 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(64):14728-14734
Though alkali metal NacNac (β-diketiminate) complexes have been utilised in synthesis as NacNac-transfer agents, studies of them in their own right with small molecules are exceptionally rare. Here, the lithium compound of the common 2,6-diisopropylphenyl-β-methyldiketiminate [NacNac(Dipp, Me)] ligand is investigated with carbon dioxide and isocyanates. In all four cases reaction occurs at the backbone γ-C atom of the NacNac ligand, which redistributes electronically into a diimine. Insertion of CO2 gives an eight-atom carboxylate (Li2O4C2) ring at the γ-C site in a dimer. Insertion of tBuNCO gives a secondary amide at the γ-C site in a monomer with TMEDA chelating lithium. Double insertion of tBuNCO and (adventitious) oxygen gives a dimer with a (LiO)2 central core involving the latter source. Insertion of less bulky (iPrNCO) gives a dimer with dimerisation through the C=O bonds of the emergent secondary amide function. 相似文献
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Robert E. Mulvey Alan R. Kennedy J. Hilko Schulte 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(11):1288-1289
The metallation reaction between dibutylmagnesium and 2,6-diisopropyl-N-(trimethylsilyl)aniline gives the unusual monomeric three-coordinate complex (diethyl ether-κO)bis[2,6-diisopropyl-N-(trimethylsilyl)anilido-κN]magnesium(II), [Mg(C15H26NSi)2(C4H10O)] or [Mg{(Me3Si)(2,6-iPr2C6H3)N}2(Et2O)]. This low-coordinate species has a distorted trigonal-planar coordination environment, with an additional short Mg—Cipso contact of 2.799 (2) Å. 相似文献
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为改善壳聚糖对细胞的特异性吸附,采用水溶性碳二亚胺将生物活性短肽精氨酸-甘氨酸-天冬氨酸-丝氨酸(RGDS)固定到壳聚糖膜的表面,采用X射线光电子能谱检测固定多肽前后的壳聚糖膜表面,发现反应后壳聚糖膜表面氮元素含量增大,Nls和Cls曲线拟合谱中酰胺键增多,表明RGDS短肽已固定到壳聚糖膜的表面;人角膜缘上皮细胞体外培养实验表明,固定RGDS后壳聚糖膜的细胞黏附率有了明显提高,固定RGDS后的壳聚糖膜在角膜组织工程支架等方面有更好的应用潜力。 相似文献
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Pablo Albors LucaM. Carrella William Clegg Pablo García‐lvarez AlanR. Kennedy Jan Klett RobertE. Mulvey Eva Rentschler Luca Russo 《Angewandte Chemie (International ed. in English)》2009,48(18):3317-3321
Check M(etal)ate: The chessboard and the figures represent a special reaction in which different low‐polarity metals can metalate arenes directly when they are brought into the right position. In a combination of queen (sodium) and knight (chromium or iron), it is possible for the knight (usually the weaker piece) to make a direct deadly hit on the king (benzene) in this game of elemental chess.
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Armstrong DR Balloch L Crawford JJ Fleming BJ Hogg LM Kennedy AR Klett J Mulvey RE O'Hara CT Orr SA Robertson SD 《Chemical communications (Cambridge, England)》2012,48(10):1541-1543
More usually thought of as a base, the sodium zincate [(TMEDA)·Na(μ-TMP)(μ-(t)Bu)Zn((t)Bu)] 1 can undergo single electron transfer with TEMPO to give [(TMEDA)·Na(μ-TMP)(μ-TEMPO(-))Zn((t)Bu)] 2 and [(TMEDA)·Na(μ-TEMPO(-))(2)Zn((t)Bu)] 3; and with chalcone [PhCOCH=CHPh] gives [{(TMEDA)·Na(μ-TMP)Zn((t)Bu)}(2)(μ-OCPhCH=CHPhCHPhCH=CPh-μ-O)] which contains two chalcone units C-C coupled though their benzylic C atoms. 相似文献
110.
García-Alvarez J Graham DV Kennedy AR Mulvey RE Weatherstone S 《Chemical communications (Cambridge, England)》2006,(30):3208-3210
The first reported sodium alkyl(TMP)aluminate reagent to be synthesised and crystallographically characterised, [TMEDA.Na(mu-TMP)(mu-(I)Bu)Al((I)Bu)2], reacts as an amido base towards phenylacetylene to form crystalline [(TMEDA)2.Na(mu-CCPh)(mu-(I)Bu)Al((I)Bu)2]; whereas the congeneric TMEDA-stabilised lithium (TMP)aluminate exhibits dual alkyl/amido basicity in its reaction with N,N-diisopropylbenzamide to form a novel heterobimetallic-heterotrianionic crystalline complex [{PhC(=O)N(iPr)2}.Li{2-[1-C(=O)N(iPr)2]C6H4}{Me2NCH2CH2N(Me)CH2}Al(iBu)2], which, in addition to having an ortho-deprotonated benzamide ligand, also contains a methyl-deprotonated TMEDA ligand and a neutral benzamide molecule ligated to lithium. 相似文献