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101.
J. C. Baird J. H. Prentice M. Monhaupt Th. von Fellenberg und Ch. Arragon Schmid 《Fresenius' Journal of Analytical Chemistry》1931,84(6-7):274-277
Ohne Zusammenfassung 相似文献
102.
Titanium‐Catalyzed Vinylic and Allylic C?F Bond Activation—Scope,Limitations and Mechanistic Insight
Dr. Moritz F. Kuehnel Philipp Holstein Meike Kliche Juliane Krüger Stefan Matthies Dominik Nitsch Joseph Schutt Michael Sparenberg Prof. Dr. Dieter Lentz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(34):10701-10714
The hydrodefluorination (HDF) of fluoroalkenes in the presence of a variety of titanium catalysts was studied with respect to scope, selectivity, and mechanism. Optimization revealed that the catalyst requires low steric bulk and high electron density; secondary silanes serve as the preferred hydride source. A broad range of substrates yield partially fluorinated alkenes, such as previously unknown (Z)‐1,2‐(difluorovinyl)ferrocene. Mechanistic studies indicate a titanium(III) hydride as the active species, which forms a titanium(III) fluoride by H/F exchange with the substrate. The HDF step can follow both an insertion/elimination and a σ‐bond metathesis mechanism; the E/Z selectivity is controlled by the substrate. The catalysts’ ineffieciency towards fluoroallenes was rationalized by studying their reactivity towards Group 6 hydride complexes. 相似文献
103.
104.
A calcium-catalyzed direct reduction of propargylic alcohols and ethers has been accomplished by using triethylsilane as a nucleophilic hydride source. At room temperature a variety of secondary propargylic alcohols was deoxygenated to the corresponding hydrocarbons in excellent yields. Furthermore, for the first time, a catalytic deoxygenation of tertiary propargylic alcohols was generally applicable. The same protocol was suitable for an efficient reduction of secondary as well as tertiary propargylic methyl, benzyl and allyl ethers. Substrates containing an additional keto-, ester or secondary hydroxyl function were reduced with exceptional chemoselectivity at the propargylic position. 相似文献
105.
MF Kuehnel P Holstein M Kliche J Krüger S Matthies D Nitsch J Schutt M Sparenberg D Lentz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(34):10701-10714
The hydrodefluorination (HDF) of fluoroalkenes in the presence of a variety of titanium catalysts was studied with respect to scope, selectivity, and mechanism. Optimization revealed that the catalyst requires low steric bulk and high electron density; secondary silanes serve as the preferred hydride source. A broad range of substrates yield partially fluorinated alkenes, such as previously unknown (Z)-1,2-(difluorovinyl)ferrocene. Mechanistic studies indicate a titanium(III) hydride as the active species, which forms a titanium(III) fluoride by H/F exchange with the substrate. The HDF step can follow both an insertion/elimination and a σ-bond metathesis mechanism; the E/Z selectivity is controlled by the substrate. The catalysts' ineffieciency towards fluoroallenes was rationalized by studying their reactivity towards Group?6 hydride complexes. 相似文献
106.
107.
Th. von Fellenberg 《Fresenius' Journal of Analytical Chemistry》1916,55(1):62-63
Ohne Zusammenfassung 相似文献
108.
109.
Th. v. Fellenberg 《Fresenius' Journal of Analytical Chemistry》1925,67(1-2):79
Ohne Zusammenfassung 相似文献
110.
G. Issoglio Th. von Fellenberg B. Lautenschl?ger Schimmel u. Co. A. W. Dox G. P. Plaisance und C. Estes 《Fresenius' Journal of Analytical Chemistry》1923,62(10):413-415
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