476429-49-9Relevant 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 (2007/10/03)
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.
