430429-32-6Relevant academic research and scientific papers
Developments in the simmons-smith-mediated epoxidation reaction
Aggarwal, Varinder K.,Coogan, Michael P.,Stenson, Rachel A.,Jones, Raymond V. H.,Fieldhouse, Robin,Blacker, John
, p. 319 - 326 (2002)
The reaction between Et2Zn, ClCH2I, sulfide, and aldehyde furnishes terminal epoxides in high yields. The reaction occurs via a zinc carbenoid, which reacts with the sulfide to furnish an ylide, which in turn reacts with the aldehyde to give the epoxide. Chiral ligands capable of chelation to zinc [1,2-amino alcohols, amino acids, bis(oxazolines), taddols] were examined, but only low enantioselectivity was observed (up to 11% ee). A number of chiral sulfides were also examined, but again only low enantioselectivity was observed (up to 16% ee). However, linking a sulfide to a metal capable of chelation to zinc [a bis(oxazoline) bearing a sulfide at the 5 position] produced a reagent that gave up to 54% ee in the epoxidation process. The same system was applied to the preparation of terminal aziridines from imines. The optimum group on nitrogen was a sulfonyl group, although groups capable of chelation of zinc (o-methoxyphenyl) were also effective. Attempts to render the aziridination process asymmetric by using the above strategy were less successful (up to 19% ee). WILEY-VCH Verlag GmbH 2002.
Bifunctional catalysts for catalytic asymmetric sulfur ylide epoxidation of carbonyl compounds
Aggarwal, Varinder K.,Bell, Louise,Coogan, Michael P.,Jubault, Philippe
, p. 2037 - 2042 (2007/10/03)
Carbonyl epoxidation using diazo compounds mediated by catalytic quantities of sulfide and metal catalyst has been investigated using sulfides linked to the metal catalyst. In this study a range of bisoxazolines with pendant sulfides were tested in the as
