Palladium-Catalyzed Synthesis of Aromatic Carboxylic Acids with Silacarboxylic Acids
摘要:
Aryl iodides and bromides were easily converted to their corresponding aromatic carboxylic acids via a Pd-catalyzed carbonylation reaction using silacarboxylic acids as an in situ source of carbon monoxide. The reaction conditions were compatible with a wide range of functional groups, and with the aryl iodides, the carbonylation was complete within minutes. The method was adapted to the double and selective isotope labeling of tamibarotene.
Halogen–magnesium exchange on unprotected aromatic and heteroaromatic carboxylic acids
作者:Felix Kopp、Stefan Wunderlich、Paul Knochel
DOI:10.1039/b618923g
日期:——
The magnesiation of halogenated aromatic and heteroaromatic carboxylic acids is accomplished by their treatment with MeMgCl in the presence of LiCl and subsequent reaction with i-PrMgCl·LiCl; the resulting double-magnesiated species react with a variety of electrophiles in up to 97% yield.
organoborons. This reaction involves base-mediated nucleophilic activation of diboron that enables transmetalation of an aryl(halo)palladium(II) intermediate with a diboron. As an alternative, herein, we have established Lewis acid-mediated conditions for borylating (pseudo)haloarenes that require no external base. The electrophilic activation of the aryl(halo)palladium(II) intermediate via dehalogenation