159042-12-3Relevant academic research and scientific papers
PROCESS FOR PRODUCING NITROGENOUS 5-MEMBERED CYCLIC COMPOUND
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Page/Page column 9, (2008/06/13)
A method of the intramolecular and intermolecular cyclization of an N-acylhydrazone for obtaining a pyrazoline skeleton or pyrazolidine skeleton under ordinary conditions with high stereoselectivity and in high yield. An N-acylhydrazone represented by the following formula (I): (wherein R1 and R2 are the same or different and each represents hydrogen or a hydrocarbon group and Ar represents an optionally substituted aromatic hydrocarbon group) is converted to an N-acylpyrazoline derivative with high stereoselectivity in the presence of a Lewis acid catalyst or asymmetric Lewis acid catalyst.
Catalytic asymmetric reductive amination of ketones via highly enantioselective hydrogenation of the C=N double bond
Burk, Mark J.,Martinez, Jose P.,Feaster, John E.,Cosford, Nick
, p. 4399 - 4428 (2007/10/02)
We describe a convenient, chemoselective asymmetric reductive amination procedure for the conversion of ketones to chiral hydrazines and amines. The key step in the three-step process is enantioselective DuPHOS-Rh-catalyzed hydrogenation of the C=N double bond of N-acylhydrazones. Detailed optimization studies revealed the effect of solvent, temperature, and the N- acyl group on the enantioselectivity and catalytic efficiency of the reaction. The reduction products, N-acylhydrazines, were converted to hydrazines or amines through hydrolysis or treatment with samarium(II) iodide, respectively.
