476429-19-3Relevant academic research and scientific papers
Efficient synthesis of α-aryl esters by room-temperature palladium-catalyzed coupling of aryl halides with ester enolates
Jorgensen, Morten,Lee, Sunwoo,Liu, Xiaoxiang,Wolkowski, Joanna P.,Hartwig, John F.
, p. 12557 - 12565 (2002)
A catalytic amount of Pd(dba)2 ligated by either carbene precursor N,N′-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazolium (1) or P(t-Bu)3 mediated the coupling of aryl halides and ester enolates to produce α-aryl esters in high yields at room temperature. The reaction was highly tolerant of functionalities and substitution patterns on the aryl halide. Improved protocols for the selective monoarylation of tert-butyl acetate and the efficient arylation of α,α-disubstituted esters were developed with LiNCy2 as base and P(t-Bu)3 as ligand. In addition, tert-butyl esters, such as those of Naproxen and Flurbiprofen, were prepared from tert-butyl propionate and aryl bromides in high yields in the presence of Pd(dba)2 and the hindered, saturated heterocyclic carbene ligand precursor.
AMINOBENZYL-SUBSTITUTED CYCLIC SULFONES USEFUL AS BACE INHIBITORS
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Page/Page column 35, (2009/04/24)
The invention relates to novel heterocyclic compounds of the formula in which all of the variables are as defined in the specification, in free form or in salt form, to their preparation, to their use as medicaments and to medicaments comprising them.
