49835-51-0Relevant academic research and scientific papers
Nitroalkenes as Latent 1,2-Biselectrophiles - A Multicatalytic Approach for the Synthesis of 1,4-Diketones and Their Application in a Four-Step One-Pot Reaction to Polysubstituted Pyrroles
Fuchs, Patrick J. W.,Zeitler, Kirsten
, p. 7796 - 7805 (2017)
An NHC-catalyzed nitro-Stetter/elimination/Stetter reaction sequence employs nitroalkenes as latent 1,2-dication synthons providing a novel access to highly useful symmetrical and unsymmetrical 2-aryl substituted 1,4-diketone building blocks from commercially available aldehyde precursors. For less activated (aliphatic) aldehydes, a cooperative catalytic strategy has been developed via the merger of NHC and H-bonding catalysis. To further showcase the versatility of our approach, a great variety of these unprecedented 1,4-diketones are used to efficiently synthesize polysubstituted pyrroles - including those with hetaryl substituents - in good to excellent yields in a multicatalytic metal-free, four-step one-pot cascade reaction under mild, yet robust, conditions.
Process for preparing ketones
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, (2008/06/13)
Ketones are prepared by reacting an aromatic or heterocyclic aldehyde in the presence of a cyanide ion with an unsaturated compound having the formula (I): STR1 wherein R1, R2 and R3 are the same or different and are selected from the group of hydrogen, optionally substituted aliphatic, cycloaliphatic, araliphatic, aromatic, heterocyclic and carboxylic acid ester and R4 is nitrile (CN), --CO--R5 or --CO--OR5 wherein R5 is selected from the group of optionally substituted aliphatic, cycloaliphatic, araliphatic, aromatic and heterocyclic and R1 and R2 and/or R1 and R3 and/or R2 and R5 or R3 and R5 together with the carbon atoms to which they are attached as substituents may also form a carbocyclic or heterocyclic ring. Ketones prepared according to the process of the invention have the formula: STR2 wherein R1 ' and R3 ' are identical or different and are selected from the group of hydrogen, lower alkyl having up to 3 C-atoms and optionally substituted phenyl; and R6 ' is optionally substituted phenyl or a pyridyl.
