119288-67-4Relevant academic research and scientific papers
Simple approach to β-lactam derivatives from N-acylimidazoles
Nahmany, Moshe,Melman, Artem
, p. 5804 - 5806 (2006)
Reaction of N-acylimidazoles possessing an electron-withdrawing group in the α position with diarylimines produces β-lactams in high yields.
Rh(II) catalysed intramolecular C-H insertion of diazo substrates in water: A simple and efficient approach to catalyst reuse
Candeias, Nuno R.,Gois, Pedro M. P.,Afonso, Carlos A. M.
, p. 391 - 393 (2005)
Water is an efficient solvent for the Rh2(OAc)4 catalysed intramolecular C-H insertion of a range of diazo substrates without competitive water insertion. Due to the high solubility and stability of the catalyst in water, the catalyst can be efficiently reused.
Application of diethyl ethynylphosphonate to the synthesis of 3-phosphonylated β-lactams via the Kinugasa reaction
Kowalski, Marcin K.,Mlostoń, Grzegorz,Obijalska, Emilia,Heimgartner, Heinz
, p. 59 - 67 (2017/02/19)
The easily available diethyl ethynylphosphonate reacts with diverse aldonitrones under Kinugasa reaction conditions at room temperature, providing 3-phosphonylated β-lactams in good yields. In all cases, the reaction led to the trans-isomer exclusively. T
Stereoselective control in the Staudinger reactions involving monosubstituted ketenes with electron acceptor substituents: Experimental investigation and theoretical rationalization
Qi, Hengzhen,Li, Xinyao,Xu, Jiaxi
experimental part, p. 2702 - 2714 (2011/05/19)
The stereoselectivity of the Staudinger reactions involving monosubstituted ketenes with electron acceptor substituents was investigated experimentally by determination of the product stereochemistry and theoretically via DFT calculations. The results indicate that imines preferentially attack the less sterically hindered exo-side of the ketenes to generate zwitterionic intermediates. Subsequently, for cyclic imines, the intermediates undergo a conrotatory ring closure directly to produce β-lactams, while for linear imines, the imine moiety of the intermediates isomerizes to more stable intermediates, which further undergo a conrotatory ring closure to afford trans-β-lactams. The steric hindrance and the isomerization, rather than the torquoelectronic effect, play crucial roles in controlling the stereoselectivity in the practical Staudinger reactions involving monosubstituted ketenes with electron acceptor substituents, although the unaccessible borylketene with a powerful electron acceptor group controls the stereoselectivity torquoelectronically, in theory.
Rh(II)-catalyzed intramolecular C-H insertion of diazo substrates in water: Scope and limitations
Candeias, Nuno R.,Gois, Pedro M. P.,Afonso, Carlos A. M.
, p. 5489 - 5497 (2007/10/03)
Preferential Rh(II) carbenoid intramolecular C-H versus O-H insertion derived from α-diazo-acetamides can be achieved in water by using an appropriate combination of the catalyst and amide groups, which creates a larger hydrophobic environment around the
Cycloaddition Reactions of (Diethylphosphono)ketenes
Motoyoshiya, Jiro,Hirata, Kozo
, p. 211 - 214 (2007/10/02)
Methyl- and chloro(diethylphosphono)ketenes were found to add to cyclopentadiene or imines in unusual manner in the certain cases.Some chemical conversions and the Horner-Wittig reaction of the cycloadducts were examined.
