The enzymatic oxidative decarboxylation of linear short-chain fatty acids (C4:0-C9:0) employing the P450 monooxygenase OleT, O2 as the oxidant, and NAD(P)H as the electron donor gave the corresponding terminal C3 to C8  alkenes with product titers of up to 0.93 g L(-1) and TTNs of >2000. Key to this process was the construction of an efficient electron-transfer chain employing putidaredoxin CamAB in combination with NAD(P)H recycling at the expense of glucose, formate, or phosphite. This system allows for the biocatalytic production of industrially important 1-alkenes, such as propene and 1-octene, from renewable resources for the first time.

Die enzymatischeo xidative Decarboxylierung von linearen kurzkettigen Fettsäuren (C4:0-C9:0) unter Verwendung der P450-Monooxygenase OleT,O 2 und NAD(P)H als Elektronendonor ermçglicht die Synthese terminaler C 3 -b is C 8 -Alkene mit Produkttitern von bis zu 0.93 gL À1 und TTNs > 2000. Essentiell für diesen Prozess war die Entwicklung einer effizienten Elektronentransferkette unter Verwendung von Putidaredoxin (CamAB) und NAD(P)H-Regeneration basierend auf Glukose,A meisensäure oder Phosphonat. Mithilfe dieses Reaktionssystems lassen sich auf biokatalytischem Wegindustriell wichtigeAlkene,wie z. B. Propen und 1-Octen zum ersten Mal vollständig aus nachwachsenden Rohstoffen herstellen. Schema 1. Oxidative Decarboxylierung gesättigter FS zu 1-Alkenen durch OleT.W eg A) Decarboxylierung langkettiger FS (C12:0-C20:0) mit H 2 O 2 über den Peroxid-Shunt. WegB)EnzymatischeR edoxkaskade zur Decarboxylierung von FS (C4:0-C22:0) unter Verwendung von O 2 und NAD(P)H-Regeneration.DH= Dehydrogenase.

We present 1D and 2D NMR experiments that provide in situ insights into photoinduced isomerizations. Irradiation during the mixing period of an exchange spectroscopy (EXSY) experiment leads to characteristic cross peaks in 2D spectra. The phototriggered exchange of magnetization occurring in photoswitchable (Z)-and (E)isomers of three selected azo compounds provides information on the dynamic E/Z equilibria. We report the dependence of the diagonal-to-cross-peak ratio on concentration, light intensity, and mixing time. In analogy to exchange spectroscopy, this ratio mirrors the efficiency of light induced molecular transformations. Furthermore, we present a time-saving 1D version and a combined light/phase cycle scheme for enhanced detectability of photoinduced changes in the spectrum. This insight into light-induced structural changes is highly suited to study macromolecules, in which photoswitchable units trigger conformational changes.

ExTra NMR utilises selectively inverted magnetisation for in situ monitoring of fast chemical processes.