Trichloromethyl ketones: asymmetric transfer hydrogenation and subsequent Jocic-type reactions with amines
作者:Michael S. Perryman、Matthew E. Harris、Jade L. Foster、Anushka Joshi、Guy J. Clarkson、David J. Fox
DOI:10.1039/c3cc46070c
日期:——
Amino-amides are important pharmaceutical building-blocks. The enantioselective reduction of trichloromethyl ketones using ruthenium transfer hydrogenation catalysts is reported. The products react in a range of Jocic-type reactions to give enantiomerically enriched amino-amides.
This invention aims at providing a catalyst for producing an optically active aldehyde or an optically active ketone, which is an optically active carbonyl compound, by carrying out selective asymmetric hydrogenation of an α,β-unsaturated carbonyl compound, particularly a catalyst which is insoluble in a reaction mixture for obtaining optically active citronellal which is useful as a flavor or fragrance, by carrying out selective asymmetric hydrogenation of citral, geranial or neral; and a method for producing a corresponding optically active carbonyl compound. The invention relates to a catalyst for asymmetric hydrogenation of an α,β-unsaturated carbonyl compound, which comprises a powder of at least one metal selected from metals belonging to Group 8 to Group 10 of the Periodic Table, or a metal-supported substance in which at least one metal selected from metals belonging to Group 8 to Group 10 of the Periodic Table is supported on a support, an optically active cyclic nitrogen-containing compound and an acid.
B(C6F5)3-Catalyzed tandem cyclization/hydrosilylation for the step-economical construction of 1,2,3,4-tetrahydroquinoxalines from readily available starting materials has been developed.
B(C6F5)3催化的串联环化/氢硅烷化反应,可从易得的起始物构建1,2,3,4-四氢喹啉。
Efficient synthesis of useful heterocycles via transition metal-catalyzed cascade processes
This paper reports our recent results from synthesis of some useful heterocycles, for example oxazolidinones, indoles, and quinoxalinones, by transition metal-catalyzed cascade processes. The scope and limitations of these procedures and the reaction mechanism for formation of the heterocycles are also discussed.
A general, straightforward, and practicalaccess to multi-substituted chiral quinoxalin-2-ones has been achieved based on the copper(I) chloride-dimethylethylenediamine (DMEDA) catalyst system. With the use of 1 mol% copper(I) chloride, structurally diverse quinoxalin-2-ones were generated with high optical purity from readily available starting materials, 2-haloanilines and α-amino acids, in a one-pot