60641-51-2Relevant academic research and scientific papers
Selective Construction of C?C and C=C Bonds by Manganese Catalyzed Coupling of Alcohols with Phosphorus Ylides
Liu, Xin,Werner, Thomas
supporting information, p. 1096 - 1104 (2020/12/31)
Herein, we report the manganese catalyzed coupling of alcohols with phosphorus ylides. The selectivity in the coupling of primary alcohols with phosphorus ylides to form carbon-carbon single (C?C) and carbon-carbon double (C=C) bonds can be controlled by the ligands. In the conversion of more challenging secondary alcohols with phosphorus ylides the selectivity towards the formation of C?C vs. C=C bonds can be controlled by the reaction conditions, namely the amount of base. The scope and limitations of the coupling reactions were thoroughly evaluated by the conversion of 21 alcohols and 15 ylides. Notably, compared to existing methods, which are based on precious metal complexes as catalysts, the present catalytic system is based on earth abundant manganese catalysts. The reaction can also be performed in a sequential one-pot reaction generating the phosphorus ylide in situ followed manganese catalyzed C?C and C=C bond formation. Mechanistic studies suggest that the C?C bond was generated via a borrowing hydrogen pathway and the C=C bond formation followed an acceptorless dehydrogenative coupling pathway. (Figure presented.).
Nucleoside analogues with a 1,3-diene-Fe(CO)3 substructure: Stereoselective synthesis, configurational assignment, and apoptosis-inducing activity
Hirschh?user, Christoph,Velcicky, Juraj,Schlawe, Daniel,Hessler, Erik,Majdalani, André,Neud?rfl, J?rg-Martin,Prokop, Aram,Wieder, Thomas,Schmalz, Hans-Günther
supporting information, p. 13017 - 13029 (2013/10/01)
The synthesis and stereochemical assignment of two classes of iron-containing nucleoside analogues, both of which contain a butadiene-Fe(CO)3 substructure, is described. The first type of compounds are Fe(CO)3-complexed 3'-alkenyl-2′,3′-dideoxy- 2′,3′-dehydro nucleosides (2,5-dihydrofuran derivatives), from which the second class of compounds is derived by formal replacement of the ring oxygen atom by a CH2 group (carbocyclic nucleoside analogues). These compounds were prepared in a stereoselective manner through the metal-assisted introduction of the nucleobase. Whilst the furanoid intermediates were prepared from carbohydrates (such as methyl-glucopyranoside), the carbocyclic compounds were obtained by using an intramolecular Pauson-Khand reaction. Stereochemical assignments based on NMR and CD spectroscopy were confirmed by X-ray structural analysis. Biological investigations revealed that several of the complexes exhibited pronounced apoptosis-inducing properties (through an unusual caspase 3-independent but ROS-dependent pathway). Furthermore, some structure-activity relationships were identified, also as a precondition for the design and synthesis of fluorescent and biotin-labeled conjugates. I gotta Fe-ling: Iron-containing nucleoside analogues, which were first synthesized during an exercise in stereoselective π-complex chemistry, exhibited pronounced cytotoxic and apoptosis-inducing activities, even against resistant cancer cell lines. Both hetero- (X=O) and carbocyclic (X=CH2) compounds were studied, and a synthetic route to R′-labeled derivatives was developed as a precondition for future biological experiments. TDS=thexyldimethylsilyl. Copyright
