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Biomedical subjects

A K Yudin

Publications and source records attributed to A K Yudin.

5 recordsLinked to original sources
PubMed2001

Olefin epoxidation with bis(trimethylsilyl) peroxide catalyzed by inorganic oxorhenium derivatives. Controlled release of hydrogen peroxide.

The replacement of organometallic rhenium species (e.g., CH(3)ReO(3)) by less expensive and more readily available inorganic rhenium oxides (e.g., Re(2)O(7), ReO(3)(OH), and ReO(3)) can be accomplished using bis(trimethylsilyl) peroxide (BTSP) as oxidant in place of aqueous H(2)O(2). Using a catalytic amount of a proton source, controlled release of hydrogen peroxide helps preserve sensitive peroxorhenium species and enables catalytic turnover to take place. Systematic investigation of the oxorhenium catalyst precursors, substrate scope, and effects of various additives on olefin epoxidation with BTSP are reported in this contribution.

Alkenes↗
PubMed2001

Combinatorial electrochemistry.

Recent advances in combinatorial electrochemistry include new methods for parallel construction of small organic molecules, synthesis of conducting materials, electroactive solid supports and heterogeneous catalysts. In addition, new instrumentation for high-throughput electrosynthesis and analysis continues to be developed at a steady pace. Future development is likely to involve miniaturization of a variety of electrosynthetic operations.

Combinatorial Chemistry Techniques↗
PubMed2000

Efficient epoxidation of alkenes with aqueous hydrogen peroxide catalyzed by methyltrioxorhenium and 3-cyanopyridine.

The epoxidation of alkenes with 30% aqueous hydrogen peroxide is catalyzed efficiently by methyltrioxorhenium (MTO) in the presence of pyridine additives. The addition of 1-10 mol % of 3-cyanopyridine increases the system's efficiency for terminal and trans-disubstituted alkenes resulting in high isolated yields of the corresponding epoxides. The system allows for epoxidation of alkenes with various functional groups. Alkenes leading to acid-sensitive products are efficiently epoxidized using a mixture of pyridine and 3-cyanopyridine as additives. This method is operationally very simple and uses an environmentally benign oxidant. The effects of different pyridine additives on the alkene conversion and the catalyst lifetime are discussed.

Alkenes↗
PubMedDate not supplied

Parallel electrosynthesis of 1,2-diamines.

Parallel reductive hydrocoupling of aldimines was performed to generate vicinal diamines using the spatially addressable electrolysis platform (SAEP). The stainless steel cathodes and sacrificial aluminum anodes were used in this electrosynthesis methodology. Introducing a large substituent on the imino nitrogen atom efficiently controls stereoselectivity of the electroreductive coupling process. This method can now be applied to the generation of libraries of 1,2-diamines, which further expands the techniques of parallel synthesis and combinatorial electrochemistry.

Combinatorial Chemistry Techniques↗