20697-83-0Relevant academic research and scientific papers
FLAVIN DERIVATIVES
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, (2011/10/31)
The present invention relates novel flavin derivatives, their use and compositions for use as riboswitch ligands and/or anti-infectives.
Helical triskelion monophosphites as ligands in asymmetric catalysis
Reetz, Manfred T.,Guo, Hongchao,Jun-An, Ma.,Goddard, Richard,Mynott, Richard J.
supporting information; experimental part, p. 4136 - 4142 (2009/09/05)
Members of a new family of chiral triskelion P ligands, namely helical C3-symmetric monophos- phites P(OR)3, have been prepared in two steps Dy monoacylation of (R)- or (S)-1,1'-binaphthyl-2,2'-diol (BINOL) or diphenol using a carboxylic acid chloride followed Dy PCl3 phosphorylation. The most sterically hindered member of these monophosphites, derived from the compound accessible by monoacylation of BINOL using adamantane carboxylic acid chloride, has been characterized by X-ray crystallography and NMR spectroscopy as a single well-defined compound. It exists exclusively in the syn conformation, with a propeller-like (twisted) geometry resulting in helicity. Upon utilization of(R)- or (S)-BINOL in the two-step synthesis, the helicity proves to be P or M, respectively. When used as ligands in the Rh-catalyzed asymmetri c hydrogenation of prochiral homoallylic alcohols, these bulky helical ligands lead to respectable enantioselectivities (79-98percent ee). In contrast, the less sterically congested and more flexible BINOL-derived phenyl analogue exists in several conformeric forms, even in the crystal, and this leads to poor enantioselectivity in the model reactions (ee = 32percent). For the purpose of structural comparison, the analogous monophosphites derived from diphenol were also prepared and characterized. These compounds, again in contrast to the BINOL-derived adamantyl derivatives, occur in several different conformeric states.
Breaking of the C-C bond of cyclobutanones by rhodium(I) and its extension to catalytic synthetic reactions
Murakami,Amii,Shigeto,Ito
, p. 8285 - 8290 (2007/10/03)
A study of rhodium(I)-catalyzed synthetic transformations involving selective breaking of the C-C bond α to the carbonyl group of cyclobutanones is described. Decarbonylation took place on treatment of a cyclobutanone with an equimolar amount of (Ph3
