- Efficient Pd-Catalyzed Regio- and Stereoselective Carboxylation of Allylic Alcohols with Formic Acid
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Formic acid is efficiently used as a C1 source to directly carboxylate allylic alcohols in the presence of a low loading of palladium catalyst and acetic anhydride as additive to afford β,γ-unsaturated carboxylic acids with excellent chemo-, regio-, and stereoselectivity. The reaction proceeds through a carbonylation process with in situ-generated carbon monoxide under mild conditions, avoiding the use of high-pressure gaseous CO. A bisphosphine ligand with a large bite angle (4,5-bis{diphenylphosphino}-9,9-dimethylxanthene, Xantphos) was found to be uniquely effective for this transformation. The regio- and stereoconvergence of this reaction is ascribed to the thermodynamically favored isomerization of the allylic electrophile in the presence of the palladium catalyst.
- Fu, Ming-Chen,Shang, Rui,Cheng, Wan-Min,Fu, Yao
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supporting information
p. 8818 - 8822
(2017/07/11)
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- Highly enantioselective [3+2] coupling of cyclic enamides with quinone monoimines promoted by a chiral phosphoric acid
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Enantioselective [3+2] coupling of cyclic enamides with quinone monoimines was realised using a chiral phosphoric acid as a catalyst. This transformation allowed for the synthesis of highly enantioenriched polycyclic 2,3-dihydrobenzofurans (up to 99.9% ee). The absolute configuration of one product was determined by an X-ray crystal structural analysis. We also found a possible mechanism for this reaction.
- Zhang, Minmin,Yu, Shuowen,Hu, Fangzhi,Liao, Yijun,Liao, Lihua,Xu, Xiaoying,Yuan, Weicheng,Zhang, Xiaomei
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supporting information
p. 8757 - 8760
(2016/07/15)
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- PYRIDAZINONE COMPOUNDS AS CALCILYTICS
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Various calcilytic compounds and pharmaceutical compositions containing these compounds are disclosed. Calcilytic compounds are compounds capable of inhibiting calcium receptor activity. Methods for preparing calcilytic compounds, oral bioavailability of calcilytic compounds, and their use as calcium receptor antagonists are also disclosed.
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Page/Page column 26
(2010/11/27)
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- BICYCLIC SUBSTITUTED INDOLE-DERIVATIVE STEROID HORMONE NUCLEAR RECEPTOR MODULATORS
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The present invention provides a compound of the formula: Formula (I); or a pharmaceutically acceptable salt thereof, pharmaceutical compositions comprising an effective amount of a compound of Formula I in combination with a suitable carrier, diluent, or excipient, and methods for treating physiological disorders, particularly congestive heart disease, hypertension, and atherosclerosis, comprising administering to a patient in thereof an effective amount of a compound of Formula I. X-16125
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Page/Page column 51
(2010/02/14)
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- Synthesis of 6/7-halotetralones
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The title compounds were prepared from halobromobenzenes via a palladium catalysed coupling followed by cyclisation.
- Owton,Brunavs
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p. 981 - 987
(2007/10/02)
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