Rh(<scp>ii</scp>) catalysed intramolecular C–H insertion of diazo substrates in water: a simple and efficient approach to catalyst reuse
作者:Nuno R. Candeias、Pedro M. P. Gois、Carlos A. M. Afonso
DOI:10.1039/b414233k
日期:——
Water is an efficient solvent for the Rh2(OAc)4 catalysedintramolecular 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.
C−H Carbene Insertion of α-Diazo Acetamides by Photolysis in Non-Conventional Media
作者:Nuno R. Candeias、Pedro M. P. Gois、Luis F. Veiros、Carlos A. M. Afonso
DOI:10.1021/jo800980c
日期:2008.8.1
Light from a mercury vapor high-pressure lamp was used to induce the photolytic decomposition of alpha-diazo acetamides in hexane and in nonconventional media such as water or a film. The corresponding beta- and/or gamma-lactams were obtained in reasonable yields and in some cases with good diastereoselectivities with no need to use a metallic catalyst. Experimental studies on chiral substrates demonstrated the occurrence of insertion with retention of configuration.
Rh(II)-Catalyzed Intramolecular C−H Insertion of Diazo Substrates in Water: Scope and Limitations
作者:Nuno R. Candeias、Pedro M. P. Gois、Carlos A. M. Afonso
DOI:10.1021/jo060397a
日期:2006.7.1
Preferential Rh(II) carbenoid intramolecular C-H versus O-H insertion derived from R-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 reactive carbenoid center.