scholarly journals Changes of pH and Energy State in Subacute Human Ischemia Assessed by Multinuclear Magnetic Resonance Spectroscopy

Stroke ◽  
2015 ◽  
Vol 46 (2) ◽  
pp. 441-446 ◽  
Author(s):  
Johann Philipp Zöllner ◽  
Elke Hattingen ◽  
Oliver C. Singer ◽  
Ulrich Pilatus
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Energy State ◽  
Resonance Spectroscopy ◽  
Multinuclear Magnetic Resonance

Reactivity of Alkoxyethynyl(trimethyl)silane, -germane and -stannane towards Trialkylboranes. Organometallic-Substituted Enol Ethers

2003 ◽  
Vol 58 (11) ◽  
pp. 1035-1040 ◽  
Author(s):  
Bernd Wrackmeyera ◽  
Sergej V. Gruener ◽  
Alla S. Zolotareva
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Room Temperature ◽  
Quantitative Yield ◽  
Resonance Spectroscopy ◽  
Enol Ethers ◽  
Multinuclear Magnetic Resonance

Abstract Methoxyethynyl(trimethyl)silane (1a) reacts at 100°C very slowly with triethylborane (4) to give a mixture of alkenes, one of which is the 1,1-organoboration product (Z)-1-methoxy-1-trimethylsilyl- 2-diethylboryl-but-1-ene (7a). Methoxyethynyl(trimethyl)germane (2a) reacts within minutes at 60 - 70°C with 4, tripropylborane (5) and 9-ethyl-9-borabicyclo[3.3.1]nonane (6) by 1,1-organoboration in the usual regio- and stereospecific way to give the corresponding alkenes (9a - 11a). The analogous reactions of the ethoxyethynyl(trimethyl)germane (2b) require longer heating and are accompanied by decomposition of 2b. Ethoxyethynyl(trimethyl)stannane (3b) reacts with the trialkylboranes 4- 6 already below room temperature by 1,1-organoboration to give the alkenes (12b - 14b) in quantitative yield. The compound 3b also reacts with the alkenes, e.g. 9a, 13b, 14b, to give novel organometallicsubstituted dienes. All products were characterised by multinuclear magnetic resonance spectroscopy (1H, 11B, 13C, 29Si, and 119Sn NMR).

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