ChemInform Abstract: Room-Temperature Palladium-Catalyzed Cross-Coupling of Aryltrimethylammonium Triflates with Aryl Grignard Reagents.

ArticleinOrganic Letters 12(19):4388-91 · October 2010with8 Reads
DOI: 10.1021/ol1018739 · Source: PubMed
Abstract
Aryltrimethylammonium triflates and tetrafluoroborates were found to be highly reactive electrophiles in the Pd-catalyzed cross coupling with aryl Grignard reagents. The coupling reactions proceed at ambient temperature with a nearly stoichiometric quantity of Grignard reagent, and diverse functionality is tolerated. Competition experiments established the reactivity of PhNMe(3)OTf relative to PhCl, PhBr, PhI, and PhOTf.
    • "We preferred [ 18 F]-SFB as labeling agent over nucleophilic substitution with 18 F to avoid possible hydrolysis or degradation of the sensitive diphenylphosphonate group. Precursor 15 and cold standard for SFB were synthesized as described in the literature [30]. To prepare [ 18 F]-SFB we slightly modified the one pot three steps procedure described in the literature by Scott and Shiao [41]. "
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