6 research outputs found
Triazene als photolabile Ankergruppen in der Festphasen- und Oberflächenchemie sowie Versuche zur Immobilisierung chiraler N-heterocyclischer Carbene
Triazene als photolabile Ankergruppen in der Festphasen- und Oberflächenchemie sowie Versuche zur Immobilisierung chiraler N-heterocyclischer Carbene
A triazene-based new photolabile linker in solid phase chemistry
An extension of the T2 linker methodology by showing its applicability as a photocleavable linker is reported. Photocleavage was carried out with 355 nm UV laser irradiation (3Omega Nd-YAG) in methanol/diethyl ether and is suitable for protected amino acid derivatives, as well as simple small organic molecules including resin-bound biotin. The linker is stable under a wide range of conditions with the exception of strongly acidic medi
NMR Spectroscopic Study of the Aldoxane Formation in Aqueous Acetaldehyde Solutions
Crotonaldehyde
is an interesting intermediate in the chemical industry.
It is usually produced from aqueous acetaldehyde in a two step process
in which the first step is carried out under basic and the second
step under acidic conditions. It is commonly assumed that acetaldehyde
is converted in the first step to acetaldol and that acetaldol is
subsequently dehydrated in the second step to crotonaldehyde. We demonstrate
by <sup>1</sup>H and <sup>13</sup>C NMR spectroscopic studies that
acetaldol is hardly present in the reacting solutions at lower temperatures
and that the key intermediate is aldoxane (2,6-dimethyl-1,3-dioxane-4-ol).
For the first time, data on the chemical equilibrium of the aldoxane
formation in aqueous acetaldehyde solutions is provided. Furthermore,
preliminary information on the kinetics of that reaction is presented