Spiro[indene-1,4′-oxa-zolidinones] Synthesis via Rh(III)-Catalyzed Coupling of 4-Phenyl-1,3-oxazol-2(3<i>H</i>)-ones with Alkynes: A Redox-Neutral Approach
作者:Zhongsu Liu、Wenjing Zhang、Shan Guo、Jin Zhu
DOI:10.1021/acs.joc.9b01804
日期:2019.9.20
C-H activation synthesis of heterocyclic spiro[4,4]nonanes has persistently witnessed the use of additional stoichiometric transition-metal oxidant when employing C═C bond as the spiro ring closure site. Herein, we have addressed the issue by reporting a redox-neutral strategy for spiro[indene-1,4'-oxa-zolidinones] synthesis via Rh(III)-catalyzed coupling of 4-phenyl-1,3-oxazol-2(3H)-ones with alkynes
The present invention relates to 3,8-diaza-bicyclo[4.2.0]oct-3-yl amide derivatives of formula (I), wherein the relative configuration of the diazabicyclooctane moiety is cis; and wherein Ar1, and Ar2 are as described in the description, to their preparation, to pharmaceutically acceptable salts thereof, and to their use as pharmaceuticals, to pharmaceutical compositions containing one or more compounds of formula (I), and especially to their use as orexin receptor antagonists.
The present invention relates to 3,8-diaza-bicyclo[4.2.0]oct-8-yl amide derivatives of formula (I) Formula (I) wherein the relative configuration of the diazabicyclooctane moiety is cis; and wherein Ar1, and Ar 2 are as described in the description, to their preparation, to pharmaceutically acceptable salts thereof, and to their use as pharmaceuticals, to pharmaceutical compositions containing one or more compounds of formula (I), and especially to their use as orexin receptor antagonists.
Asymmetrichydrogenation of 4-substituted cyclic enamido esters catalyzed by a rhodium–TangPhos complex provides an efficient method for the synthesis of chiral 4-substituted oxazolinones with excellent yields and good enantioselectivities. The products are valuable chiral building blocks and the applications as chiral auxiliaries and pharmaceuticals are well-known.
Efficient Access to Chiral 2-Oxazolidinones via Ni-Catalyzed Asymmetric Hydrogenation: Scope Study, Mechanistic Explanation, and Origin of Enantioselectivity
Cheap transition metal Ni-catalyzed asymmetric hydrogenation of 2-oxazolones was successfully developed, which provided an efficient synthetic strategy to prepare various chiral 2-oxazolidinones with 95%–99% yields and 97%−>99% ee. The gram-scale hydrogenation could be proceeded well with >99% ee in the presence of low catalyst loading (up to 3350 TON). This Ni-catalyzed hydrogenation protocol demonstrated