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The reactions of dipotassium germacyclopentadienediide with two Group 13 dichlorides, Cp*BCl2 and Cp*AlCl2, yield two structurally different products. In the case of boron a borole complex of germanium(ii) is obtained. The aluminium halide gives an unprecedented neutral germaaluminocene. Both compounds were fully characterised by multinuclear NMR spectroscopy supported by DFT computations. The molecular structure of the germaaluminocene was determined by XRD.Boron vs. aluminum: the synthesis of a borole complex of Ge(ii) is reported. Changing just the element from boron to aluminum unexpectedly yields an unprecedented neutral germaaluminocene. 相似文献
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Marius Durea Van Ngai Huynh Huu Tron Nguyen Radu Strugariu 《Journal of Mathematical Analysis and Applications》2014
The paper concerns a new method to obtain a proof of the openness at linear rate/metric regularity of composite set-valued maps on metric spaces by the unification and refinement of several methods developed somehow separately in several works of the authors. In fact, this work is a synthesis and a precise specialization to a general situation of some techniques explored in the last years in the literature. In turn, these techniques are based on several important concepts (like error bounds, lower semicontinuous envelope of a set-valued map, local composition stability of multifunctions) and allow us to obtain two new proofs of a recent result having deep roots in the topic of regularity of mappings. Moreover, we make clear the idea that it is possible to use (co)derivative conditions as tools of proof for openness results in very general situations. 相似文献
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Visible Light‐Promoted Decarboxylative Di‐ and Trifluoromethylthiolation of Alkyl Carboxylic Acids 下载免费PDF全文
Dr. Lisa Candish Lena Pitzer Dr. Adrián Gómez‐Suárez Prof. Dr. Frank Glorius 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(14):4753-4756
Described herein is a new and straightforward decarboxylative di‐ and trifluoromethylthiolation of alkyl carboxylic acids promoted by visible light. This approach enables the synthesis of biologically relevant alkyl SCF2H and SCF3 compounds from cheap and abundant carboxylic acids. The method is operationally simple, using irradiation from household light sources, and its mild reaction conditions make it tolerant of a range of functional groups. The strategy employs electrophilic phthalimide‐derived di‐ and trifluoromethylthiolation reagents and exploits the ability of the imidyl radical to carry a radical chain. 相似文献
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Lena Freimuth Prof. Dr. Jens Christoffers 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(22):8214-8221
The fluorescent diaminoterephthalate scaffold was equipped by amidation with three types of reactive functions: thiols for metal‐surface binding, alkynes for click reactions, and maleimides for ligation with proteins. Starting from a succinyl succinate derivative with two orthogonally cleavable ester functions, three monoamides (38–57 % yield over three steps) and two bisamides (19 and 25 % yield over five steps) were prepared. Although alkyne and thiol derivatized compounds showed reasonable luminescence behavior (Φ≈1–4 %), the fluorescence was quenched by the maleimide moiety. It was turned on (10‐ to 20‐fold increase of fluorescence quantum yield) by conjugate addition of thiols. 相似文献