51673-61-1Relevant academic research and scientific papers
Catalytic enantioselective synthesis of difluorinated alkyl bromides
Levin, Mark D.,Ovian, John M.,Read, Jacquelyne A.,Sigman, Matthew S.,Jacobsen, Eric N.
, p. 14831 - 14837 (2020)
We report an iodoarene-catalyzed enantioselective synthesis of β,β-difluoroalkyl bromide building blocks. The transformation involves an oxidative rearrangement of α-bromostyrenes, utilizing HF-pyridine as the fluoride source and m-CPBA as the stoichiometric oxidant. A catalyst decomposition pathway was identified, which, in tandem with catalyst structure-activity relationship studies, facilitated the development of an improved catalyst providing higher enantioselectivity with lower catalyst loadings. The versatility of the difluoroalkyl bromide products was demonstrated via highly enantiospecific substitution reactions with suitably reactive nucleophiles. The origins of enantioselectivity were investigated using computed interaction energies of simplified catalyst and substrate structures, providing evidence for both CH-πand π-πtransition state interactions as critical features.
Quinoline derivatives as immunostimulants
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, (2008/06/13)
This invention relates to compounds of the formula STR1 wherein R1, R2, R3, R4, R5, R6 and R7 are as defined hereinbelow that exhibit activity as immunostimulants.
