86129-99-9Relevant articles and documents
Trio catalysis merging enamine, br?nsted acid, and metal lewis acid catalysis: Asymmetric three-component aza-diels-alder reaction of substituted cinnamaldehydes, cyclic ketones, and arylamines
Deng, Yongming,Kumar, Siddhartha,Wheeler, Kraig,Wang, Hong
, p. 7874 - 7880 (2015)
A trio catalyst system, composed of arylamine, BINOL-derived phosphoric acid, and Y(OTf)3, enables the combination of enamine catalysis with both hard metal Lewis acid catalysis and Br?nsted acid catalysis for the first time. Using this catalyst system, a three-component aza-Diels-Alder reaction of substituted cinnamaldehyde, cyclic ketone, and arylamine is carried out with high chemo- and enantioselectivity, affording a series of optically active 1,4-dihydropyridine (DHP) derivatives are obtained in 91-99 % ee and 59-84 % yield. DHPs bearing a chiral quaternary carbon center are also obtained with good enantioselectivity and moderate yield (three examples). Preliminary mechanistic investigations have also been conducted.
Understanding α,β-unsaturated imine formation from amine additions to α,β-unsaturated aldehydes and ketones: An analytical and theoretical investigation
Calow, Adam D. J.,Carbó, Jorge J.,Cid, Jessica,Fernández, Elena,Whiting, Andrew
supporting information, p. 5163 - 5172 (2014/06/23)
A combination of in situ IR spectroscopy (ReactIR) and DFT calculations have been used to understand what factors govern the selectivity in the addition of primary amines to α,β-unsaturated aldehydes and ketones, i.e., 1,2- versus 1,4-addition. It has been found that the 1,2-addition products (α,β-unsaturated imines following addition and elimination) usually predominate for most systems. However, exceptions, such as methyl vinyl ketone, selectively give 1,4-addition products. This has been rationalized by DFT calculations that show that major conformational effects are involved, controlled mainly by steric effects of carbonyl substituents, resulting in a model that provides simple and predictable preparation of α,β- unsaturated imines for in situ utilization in synthesis.
One - Pot Reformatsky-Imine addition reaction-leading to the synthesis of structurally diverse β-lactams
Rajput, Jaspreet,Singh, Baldev,Singal, Kewal Krishan
, p. 643 - 648 (2008/09/18)
The Reformatsky-imine addition reaction of a-bromoethylacetate with aldimines derived from 3,4-methylenedioxy benzaldehyde and α- methylcinnamaldehyde has provided an efficient and practical access to structurally diverse β-lactams. All the new β-lactams
