Palladium-Catalyzed Asymmetric Hydrogenation of α-Acyloxy-1-arylethanones
摘要:
First hand: The first example of a palladium-catalyzed asymmetric hydrogenation of α-acyloxy ketones (1) was accomplished to give the hydrogenated products 2 with by far the highest catalytic efficiency in up to quantitative conversions and excellent enantioselectivities. The hydrogenated products could serve as important intermediates for the preparation of many drug candidates. TFE=2,2,2-trifluoroethanol.
A chemoselective C−O bond cleavage of the ester alkyl side‐chain of α‐acyloxy ketones was realized for the first time by a highly efficient palladium‐catalyzed hydrogenolysis (S/C=6000, the highest catalytic efficiency by far). Furthermore, a kinetic resolution of α‐acyloxy ketones was first developed by enantioselective hydrogenolysis with good yields and up to 99 % ee.
通过高效钯催化的氢解反应(S / C = 6000,迄今为止最高的催化效率),首次实现了α-酰氧基酮的酯烷基侧链的化学选择性C-O键断裂。此外,首先通过对映选择性氢解反应开发了α-酰氧基酮的动力学拆分方法,该方法具有良好的收率和高达99%ee的收率。
Sarkhel, B. K.; Srivastava, Jagdish N., Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 1980, vol. 19, # 2, p. 158 - 159
The invention relates to new flavone derivatives which have at least one N-disubstituted carbamoyloxy unit (OOCNR6(R7)) coupled directly to one or both aromatic rings of the flavone molecule.