1256169-81-9Relevant academic research and scientific papers
Propionic Acid Derivatives and Methods of Use Thereof
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Paragraph 1794; 1795, (2018/11/21)
Provided herein are compounds and pharmaceutical compositions of formula I where R1, R2, R3, R4, R5 and R6 are as described herein. Also provided pharmaceutically acceptable salts or stereoisomers of these compounds. In addition methods are provided for inhibiting the binding of an integrin to treat various pathophysiological conditions.
Negishi cross-coupling reaction catalyzed by an aliphatic, phosphine based pincer complex of palladium. biaryl formation via cationic pincer-type Pd IV intermediates
Gerber, Roman,Blacque, Olivier,Frech, Christian M.
experimental part, p. 8996 - 9003 (2011/10/31)
The aliphatic, phosphine-based pincer complex [(C10H 13-1,3-(CH2P(Cy2)2)Pd(Cl)] (1) is a highly active Negishi catalyst, enable to quantitatively couple various electronically activated, non-activated, deactivated, sterically hindered and functionalized aryl bromides with various diarylzinc reagents within short reaction times and low catalyst loadings. Experimental observations strongly indicate that a molecular mechanism is operative with initial chloride dissociation of 1 and formation of the cationic T-shaped 14e- complex [(C10H13-1,3-(CH2P(C6H 11)2)2)Pd]+ (B), which undergoes oxidative addition of an aryl bromide (Ar′Br) to yield the cationic, penta-coordinated aryl bromide pincer complexes of type [(C10H 13-1,3-(CH2P(Cy2)2)Pd(Br) (aryl′)]+ (C) with the metal center in the oxidation state of +IV and the aryl unit in cis position relative to the aliphatic pincer core. Subsequent transmetalation with Zn(aryl)2 result in the cationic diaryl pincer complexes of type [(C10H13-1,3-(CH 2P(Cy2)2)Pd(aryl)(aryl′)]+ (D), which reductively eliminate the coupling products, thereby regenerating the catalyst. The neutral square planar aryl pincer complex - a possible key intermediate in the catalytic cycle - was found to be reversibly formed in the reaction mixture but is not involved in the catalytic mechanism. Similarly, palladium nanoparticles as the catalytically active form of 1 could have been excluded. The Royal Society of Chemistry 2011.
